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#1
06-04-2012, 09:34 AM
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Yerf dog scout atv gy6 problems
I have a yergdog scout with issues. It had been sitting a long time because
of starting and chain issues. It was always hard to start but ran well. Finally got the chain to stop falling off. I cleaned the carb but still hard to start when cold. I used a bread bag tie to clean all thee orifices and carb cleaner. runs smooth when it gets going but will not rev past half way when riding. The peddle does nothing after pushing it past half way. It will only rev so high when riding. It will slow right down on a hill and will only creep up till it is on a flat area and then is better. Cleaned the carb with carb cleaner and used bread bag wire to clean all orifices. The air/mixture screw does not seem to do much. If you turn it all the way in, it still runs. Turn it out 3-4 turns and still the same. Cleaned the roller weights and rounded off slight flat spots. Also have 15g weights on order and new clutch spring to see if that will help. I watched the cuv belt run as i had it jacked up and seems to be doing what it should. Does any one have any ideas? I also have a new carb on order from china. The air filter is clean and no restiction in the exhaust. any help will be appreciated thanks Larry |
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#2
06-04-2012, 11:16 AM
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Welcome - have you adjusted the valves yet?
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#3
06-04-2012, 12:37 PM
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No I have not yet. I took the cover off and it looked great. It ran great a couple years ago. whould the valves change not being used? I think the gap is suppose to be 2-3 thousdands of inch. Will check that and adjust. Still trying to find out if it may be the cdi which is very hard to find a replacement since it is bigger than the gy6 ones.
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#4
06-04-2012, 09:54 PM
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What did you do to fix your chain problem? I got a I think a 1 1/2" pipe floor flange and drilled out the holes cut it in half and ground out the center to use for a spacer and it worked great. but now the dang thing keeps breaking the tensioner stud off. I think the chain has 2 much play and It dont have the tensioner spring on it becouse I cant figure out how it goes. (wasnt on when I got it)
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#8
06-05-2012, 10:04 AM
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I also have a carb coming from china for it that is for the GY6. Hope it works and that the mixture screw does something since the original carb that is on it does not seem to be able to adjust. I turn the screw in to the stop and it still runs. Turned it out 2-3 turns and still runs. turn it out 4 turns and it boggs on the revs.
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#9
06-05-2012, 11:16 AM
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SycArms is dealer on this forum that can help you with your Scout parts. Buggy Depot in VA, BMI Karts in OH and Kart Mart in KS also have parts for Yerf-Dogs. SycArms is out of MS, so service, parts and response will be much quicker than going to a vendor in China.
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#10
06-05-2012, 09:25 PM
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GY6 Yerfdog Scout...is it the carb or cdi??
If my yerdog will not go up a hill what could it be? Before I buy a new cdi, how would I know if the CDI is going bad? It starts and runs great on a flat peice of land. I try to come up my driveway and it slows right down. Someone said adjust the valves. Now it will not even creep up the hill. The engine revs to half peddle and nothing different btwn 1/2 way and the floor
Just replaced the clutch and spring on the cvt still no better. Could it be the carb is shot or the cdi is going?? Thanks for all the suggestions. Just want to get this thing to climb the drive way. The cvt belt looks like the day it was put in. |
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#12
06-05-2012, 11:30 PM
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I agree with GX150- the quickest thing to make a motor powerless is a leaking intake or a dirty carb. Generally carbs don't get shot! they just get blockages that prevent optimum performance. CDI's seldom fade out,(they work or they don't), now coils can have reduced performance when hot- check your spark to see if it's bright blue. Did you check the rollers/sliders in the variator when you changed the clutch & spring?Have you viewed the CVT with the cover off (wheels elevated) just to verify everything is working properly. A variator with wore out rollers won't close all the way.
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#13
06-05-2012, 11:47 PM
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I had taken the rollers out and cleaned them all and used a lite sand paper to smooth them back off. I watched it and reved it up and the belt is moving to the top of the variater nicely when off the ground. I will check for leaks in the intake btwn the carb and engine. Could the air mixture screw wear out?
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#14
06-06-2012, 12:05 AM
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Your fuel/air mix screw is just a tapered shaft- I guess after thousands of hours it could round the tip enough to make an adjustment neccessary!!! I'm betting when you put on the new carb your issues will probably go away!!! you've already eliminated most of the typical issues already.
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#15
06-06-2012, 01:33 AM
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The air/fuel screw usually has a little o-ring sealing it. If this o-ring fell out or is damaged, air will get sucked in. When you check for leaks, spray carburetor cleaner around the couplings and joints in addition to that screw while the engine is idling. If the idle changes, you found a leak.
Since your carburetor has a manual choke, make sure that the mechanism is working properly. It will not hurt for you to check for leaks here also. |
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#16
06-06-2012, 01:15 PM
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Thanks again for the info. I did find a small leak and think I have that taken care of. Now is there some kind of clutch within the thansmission? The CVT is all nice and clean.
When I drained the transmission, I could not get the fill screw open...so there was a small tube coming out of the top of the trans (that hangs down the back end) and I filled it threw there. Thought it was just a breather tube but wonder if I got trans fluid on something I should not have?? OR could it be to much trans fluid? The new clutch for the CVT did not have much thicker pads on it than the one I took out. The engine is running much better now but still will not climb the incline on the driveway Thanks again |
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#17
06-07-2012, 11:35 AM
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Got the carb running well. I took the cover off the cvt and watched it as I drove. The belt is not coming out past the 1/2 way point. It does when the wheels are off the ground but not under load. Could it be the roller weights?
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#18
06-07-2012, 12:29 PM
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Quote:
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#19
06-07-2012, 12:45 PM
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The transmission fluid will not affect the operation as you described (it is 80w-90 gear oil). If you fill the final transmission using the fill bolt, you will fill it to the bottom of the bolt opening which is about even with bottom of the output shaft. Overfilling the transmission may result in some oil leaking out of the seals until the level drops. You said you sanded down your rollers, so I suspect they are worn and catching in the variator ramp. I suggest ordering 12g slider weights instead of rollers. They will react a little slower to engine speed changes, but will last much longer than roller weights.
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#20
06-07-2012, 05:40 PM
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I re adjusted the carb and valves today so is running well. Got a feller gauge and opened the gap on the plug to 0.23 as the book advised.
Still hard to start. The manual choke seems to flood it. Watched the variater and it is only letting the belt out 1/2 way when riding it. This thing used to go like a bat out of hell. I used to push round rolls of hay with it. Adjusted the gear cable a bit but not sure if it made a difference. It is atleast coming up the driveway a bit better but still real slow. Tried coming up the lawn up which is steeper and it just sat there. Stopped at the Honda dealer and he is getting me a set of roller weights to see if that helps. I also ordered a new belt online to see if that helps. This atv has 321hrs x 10 so guess that is about 3210 hrs. I do not think the gauge is working anymore. The trans fluid that come out when I changed it was milky looking. Must have had water in the fluid. Again thanks guys for all the help |
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#22
06-07-2012, 08:11 PM
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The belt I ordered was a 732-20-30. It is burned in my memory. The honda kid was nice. The yamaha parts guy is jerk. He never helps with anything. The Honda kid said they have them in the automatic honda scooters and showed me a diagram and looks just like mine. It did not have the grams but will try them when I get them tuesday.
Mine were the original and had some flat spots on them. I tried to lightly sand them to smooth the ridges and think that did not help the problem. |
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#23
06-07-2012, 09:11 PM
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Quote:
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#25
06-07-2012, 09:44 PM
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Your motorcycle guy is correct about the belt wear.
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#26
06-08-2012, 07:21 PM
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Need help installing new chinese carb
Has anyone installed one of these carbs on a GY6.
It has more hoses and outlets than my original on a yerfdog scout cuv any help will be greatly appreciated Thanks |
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#27
06-08-2012, 08:28 PM
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That is a standard GY6 carburetor with electric choke. Can you remove your existing carburetor and take pictures of both sides so we can help you adapt this more common one to your Scout?
Standard GY6 carburetors have a bowl drain on the bottom that does not connect to anything, vacuum line that connects to the intake between the carburetor and engine, fuel line that goes through the fuel filter to the tank, overflow line that sits open and choke that runs to AC or switched DC power on one side through a current limiting resistor to ground on the other side. |
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#28
06-08-2012, 08:36 PM
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I think my rover has a plug for the choke thats ziptied to the frame
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#29
06-08-2012, 08:48 PM
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I will try to get pics of the old one. This new one has a round plate opposite side of the chock with a hose connected//my old one that round plate is removed. This one also has a nipple in front that goes in the botton of the carb just above and in front of the bowl and points down to the left. That is the one I am not sure of and of course they did not take a pic of that side.
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#30
06-09-2012, 07:40 AM
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does this help I could only get 1 pic to load but here is a link http://www.google.com/search?q=gy6+c...w=1038&bih=769
Last edited by Texasfisherdude; 06-09-2012 at 07:48 AM. |
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#31
06-09-2012, 11:44 AM
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Yes thank....that did help. I put the carb in and got it running at idle but bogs right down when you rev it up. checked for leaks and all seams fine. This new one has an electric choke and not sure how it operates. I hooked it up but not sure if that is the problem. How does the elec choke work. Does it have a temp regulator inside of it?
When I pulled the choke off and watched it under power and does not look like it moves in or out. Put it in the freezer to get it cold and will try it again and see if it moves. |
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#32
06-09-2012, 12:43 PM
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A BIG THANK YOU for all the help. Let the carb warm up and it runs GREAT. It is finally climbing the driveway like a bat out of hell. Just have to figure out the elec choke.
I will have to keep it now since I have all these spare parts and more on the way Again thanks so much....It was the carb all along |
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#33
06-09-2012, 01:23 PM
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When the FEV is cool it's closed(normal position)- needle is short, when power is applied it will extend,but slowly. Glad to hear you have throttle/power response now. With it not wanting to idle well at start-up then the FEV is probably the culprit. Tom w/SYC has written a great post about the quaility of these units- I hadn't given any thought about their quailty before his post, I purchased a new cheap china made FEV (pre-tested it before installation & it worked) and it didn't fix my problem, swapped it out with the original known working FEV and mine ran perfect, so there's definitely something to the quality made product. I think the cheaper made ones just don't extend fast enough & it takes several start-up attempts for it to work.
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#34
06-09-2012, 10:51 PM
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I could be wrong but I think you can take the choke off your old carb and put it on your new one. Make sure you clean it real good becouse mine was stuck open when I got mine. its in a bad place and when you wash it or it rains the water falls on the carb and can get in the choke and cause all sorts of problems.
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#36
06-10-2012, 10:13 AM
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Quote:
Without the resistor, the choke will eventually burn out. The resistor is usually a ceramic block about 1 1-2 inches long, could be made to look differently, but usually the same length and bolted to the electrical box frame.
__________________
'07 Baja Reaction '05 Yerf 3206 Front end hangin' on by a shoestring  '07 roketa gk-17 -Chassis work in progress! '08 Crossfire 150R - It lives at last! 
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#37
06-10-2012, 06:30 PM
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It was running good and I took it up the road to the next house and turned around..wot and it was great and then almost died. Back to the way it was. The choke must have gone I though so I tried to convert it to manual and that failed so i just put it back together and sealed it closed. No i am back to square one. It is back to only 1/2 peddle and nothing more. Adjusted the valves again. This carb has a deep throaty sound to it. Just about ready to set it at the road and hope some takes it
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#38
06-11-2012, 04:33 PM
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Is your gas tank clean? Do you have a good fuel filter? Kinda sounds like you sucked up some trash.
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#40
06-11-2012, 10:29 PM
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Something in carb
Quote:
Put in new gas, dry gas, and Lucas carb cleaner. I messed up the electric choke buy conneting straight to the battery, and have another one coming. I have no idea how to hook up this choke and can not find a manual choke carb that will fit it. There is a long double wire that sits on the top rail going to the back of the trans that has a conecter on the end but is not used for anyting. I was wondering if it was for an elec choke connection? |
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#42
06-12-2012, 07:00 PM
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I'd get the old carb and make sure the choke was closing all the way
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#43
06-12-2012, 10:17 PM
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I took the new carb all apart and cleaned and blue it out. I think my manifold is leaking so have a new one coming. No it bogs down the minute you give it gas. I also put the old gas filter back on and it seems to fill better.
I tooks some pics. This one of the carb I wanted to find out what the nipple is on the front lower left side. It goes in just above the bowl and has a small outlet in the manifold side of the of the throat of the carb. I also took some pics of the engine area and there is a long double wire on the rail taped down running to the back of the trans. It had a connecter on it which I took off to try to hook up the choke. It has always sat there not plugged into anything and wonder if that was there for an upgrade to electric choke. It has a black wire and a yellow wire. Any ideas?? |
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#44
06-12-2012, 10:33 PM
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Hadn't seen an outlet in the location like on yours(can't see if there's an accelerator pump right there)- when you blow through it where does the air go?
Your wire on the rear,most of the time the wire isn't much longer than needed to reach the choke location or the electrical box since the choke wire is always long.- the 2 prong plug for the choke is usually the only one like it in the electrical box (usually a purple & black wire coming from the resistor block) Does your dash have a light for forward/reverse? |
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#45
06-12-2012, 11:24 PM
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Those wires are same as mine but Mine has a plug. msm1 there are no lights on dash
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#46
06-13-2012, 06:30 AM
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this could help
http://www.*************/PDF/Yerf%20D...20Diagrams.pdf |
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#47
06-13-2012, 06:07 PM
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The nipple on the carb...when you blow into it..there is a small hole in front of the butterfully is where the air comes out. I cut off the connector on those wires in the back because the connector fit the choke connector. No the scout cuv does not have a light for forward or reverse. It is rather plain jane. Got the slider weights today so have them in with new belt and clutch and spring...so that end should be great. Just waiting on a new manifold and electric choke...will try not to fry this one.
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#49
06-15-2012, 06:23 PM
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Worked on it all day yesterday and today. I think one of the problems is the exhaust valve tapit screw stripped. Got a new one today and tried to set the valves. watched several videos and it seems so easy but still not opening up when throttled. I set the gap a 004 for both.
Yesterday I cleaned the carb again thinking maybe something got in there. Is 004 the correct gap for the valves or is there a trick to it? I had to modify the air filter since this new carb sits a bit higher and the air intake is a bit bigger. Used a couple fittings from Loews and some majic black electrical tape and it all fit well. Replaced the fuel filter and all the hoses. |
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#50
06-15-2012, 06:42 PM
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Do you have the choke hooked up? The choke is wide open (full choke) when not hooked up to voltage
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#52
06-15-2012, 08:17 PM
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I think your running to rich. If you cut off the switch you are putting it in full choke. I think this is the problem you had with the original carb i think the choke was not closing all the way. I would clean the snot out of the choke on the old carb and put it back on and see what happens.
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#53
06-15-2012, 11:01 PM
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So exactly how do these chokes work? If I hook it direct to the 12volts and leave it, wont it burn it out?. Would I be better of getting a primer pump and closing off the choke as in posts I have read?
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#54
06-16-2012, 07:37 AM
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Get a 10watt 10 ohm resister from the parts store and hook it up
or put a primer on it http://www.rc-trucks.org/gy6-engine-performance.htm Last edited by Texasfisherdude; 06-16-2012 at 08:06 AM. |
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#56
06-16-2012, 09:07 AM
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Quote:
__________________
kliff |
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#57
06-16-2012, 09:49 AM
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Ok can someone tell me if the plunger is down or up to enrich to crank.I bought one off ebay said it was for GY6 but was way to big for my carb.The one i needed was 17.96 or 17.97mm.I ame going to mod.and see if i can get this to work.
__________________
 [SIGPIC] Take What You Have and Build What You Need
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#58
06-16-2012, 10:21 AM
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Quote:
Simple way to check is hook the 2 leads across a battery, and watch the needle...might want to measure it, before adding voltage, and about 2 minutes after adding voltage. I think you'll find it extends to close off the port inside the carb.
__________________
kliff |
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#60
06-16-2012, 12:04 PM
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Today I made a gasket for the choke and closed it off completly to see if there was any difference.....none....still only get 1/2 throttle and then it sounds boggy. This carb has a bit bigger air intake than the old manual choke carb that came with it. Had to modify air filter connection.
I rechecked the valves and they are at 004. The gap on the plug is 023 It has fresh gas with no ethenol in it. Has lucas carb cleaner and dry gas in tank also. New gas filter and hoses and vacumn hoses. Had a small oil leak on the head and made a new gasket for that. Put in 14g slider weights. new belt and spring and clutch plates Now with the carb....I have to set the idle at zero and play with the mixture screw and idle screw to get it to start then it idles nice. Rev it up and 1/2 way it starts to bog. shut it off and wont start have to play with the screw again. Where do I go from here other than buying a new atv? also have a primer on order. Again thanks so much for all the help guys |
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#62
06-16-2012, 12:36 PM
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Just to confirm- the FEV is short or retracted with "no" voltage and extends when powered up.
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#64
06-16-2012, 01:18 PM
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Your gasket may have closed the external holes, but the needle in the FEV closes off INTERNAL passages, to stop gas flow. Without those internal passges closed, by the needle, it is going to continually run rich, flood, foul the plug, and loose power. Just like having the enrichener on all the time.
__________________
kliff |
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#65
06-16-2012, 01:32 PM
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OK that makes a lot of sence. I can smell the gas and the plug was black. I will take the old needle from the first choke and seal it down in there and put it back on with the gasket in place and try that. I know it is something simple because it idles so well.
thanks |
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#66
06-16-2012, 01:48 PM
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I also have a problem of loosing spark.If it isn't one thing it is another.What ever happened to the old points and reg coil.tweak carb,timing ran like striped a--ape
__________________
[SIGPIC] Take What You Have and Build What You Need
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#67
06-16-2012, 04:00 PM
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I took the choke off and put gasket cement in it and put the plunger back in.
Wouldn't the gasket that I put on covering all the holes have taken care of it? Waiting for it to dry and will reinstall it. |
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#68
06-16-2012, 10:38 PM
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And that did not work. Air/fuel mix is better on idle but boggs on wot.
Does anyone know if this can be a valve problem. I adjusted the gap to 004. Is that the best gap for this thing. I am about to give up on it. |
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#69
06-17-2012, 07:54 AM
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Heres a c&p it wouldnt let me post a link
Bogging down is usually caused by one (or more) of three things. Running rich, running lean, or a weak spark. I'll start off with a very brief explanation of what Air/Fuel mixture is. The job of a carburettor is to atomize liquid fuel by injecting it into a flowing stream of air. The mixture of this air and fuel must be rather precise in order to combust within the cylinder. If there is much air, or too much fuel being delivered you will experience power loss and/or bogging down. With that said.. lets get down to the troubleshooting: Most common cause: Running rich Running rich (too much fuel in the air/fuel mix) could be caused by several things. The most common cause is a failing automatic choke unit. The choke on the GX150 carburettor is actually an enrichening circuit and in reality does not choke off any airflow at all. The auto-choke is ON in it's natural state. A failing auto-choke remains in the ON position at all times, thus it is characterized by the buggy running fine when cold, and hardly running at all when warm. Running Lean You may be running lean (too much air in the A/F mixture) if you are: 1. Having a hard time getting the engine started, 2. Once started the throttle is very tricky, too much throttle and the engine dies, and/or 3. Engine bogs and will not go beyond a certain RPM. This is commonly caused by a deteriorated intake inlet manifold. This inlet manifold can be found connecting the carburettor to the intake side of the engine. This little elbow-shaped inlet can form dry-rotting cracks, thus becoming a major vacuum leak. Please note: when replacing the intake inlet manifold, do NOT over tighten the nuts when securing it to the cylinder head. Weak Spark If the Air/Fuel mixture getting to your engine seems fine, then you may be looking at a weak spark. Ignition troubleshooting will be covered in detail on another page. The basic rundown is this: Stator/trigger wire -> CDI -> Ignition Coil -> Spark plug. It is best to check the resistance of the parts in question. Check the Yerf Dog GX150 Service Manual to find out the correct resistance values. I couldnt find a service manual on the cuv but the spiderbox has about the same engine http://www.redcatonline.com/chinese-...l-p-10409.html Last edited by Texasfisherdude; 06-17-2012 at 07:57 AM. |
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#70
06-17-2012, 09:57 AM
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Thanks for this info. This is the problem. I will replace the manifold and start there.
I got a new stator but can not get the round stator cover off. I even broke a puller trying to remove it. When I took the plug out to test it, the spark is weak. Any tricks on how to get the stator cover off?? Thanks again |
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#71
06-17-2012, 10:11 AM
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Spray the carb and manifold with WD 40 while running if it changes the way it runs you got a air leak. If it dont you dont. I had a problem with the plug on the wire harness under the left front wheel well. That thing is in a bad place and was full of mud you might want to check it out it could be dirty. Just a thought.
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#72
06-17-2012, 10:33 AM
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http://www.youtube.com/watch?v=u8qb_5h7caU&hd=1
http://www.ebay.com/sch/i.html?_trks...uller&_sacat=0 |
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#74
06-22-2012, 05:58 AM
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Did you give up?
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#75
06-22-2012, 09:40 AM
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Not yet but have just about had it. If I had not replaced so much stuff I would have junked it.
I replaced the stator, regulator and dc cdi. I also got the primer so decided to take off the new carb and put the original carb back on. It fits much better because it is smaller than the new one was and less tubes. Now I have real good spark. I also changed out the the rocker arm set and re-timed it. On the flywheel it has a t and just above it has an f . I have it set at the t and the cam gear lined up. Set intake at 003 and exhaust at 004. Now it will not start or even sound like it is catching at all. I know this has a chain tensioner for the cam. I wonder if that needs to be adjusted. Saw a video that said it self adjusts?? Just wish I could take the engine out of it to work on. It is a bugger to get to everything. When you crank it , you can tell by the sound if it is getting to much fuel or air. When you pull the throatle just a bit, the sound changes and it will not turn over well. The wires on the regulater are different colors than original but bought it from BMI and it was the one listed for the cuv so am sure it is the right one. I got the dc cdi and it is a bit smaller than the original but bigger than the ac cdi that came with the new coil. The cdi has 4wires and 2wires. I think now it must be timing issue and can not figure where to go from here. I did not change out the cam because I did not want to disturb the chain so may try that today. |
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#76
06-22-2012, 10:11 AM
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Don't rely on the flywheel timing marks. remove the spark plug and insert a straw or Popsicle stick in the hole to get the piston to TDC (top dead center). You can mark/verify your TDC on the flywheel and then make sure the two small holes in the cam line up with the top edge of the head. If these are lined up, your valves are timed properly.
To adjust the valve clearance (lash), the piston must be at its compression stroke. This determined by the cam since the cam only turns half as fast as the engine. if you see a big hole in the cam sprocket pointing toward your seat, your seat you are your compression and can adjust lash. if you do not see it, rotate the crank 360 degrees to get it off the exhaust stroke. |
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#77
06-22-2012, 05:40 PM
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OK I found a problem today. The new manifold is shorter on the bottom than the old one and was not screwing down tight to the head.
When I primed it, the gas ran out over the head. This was after redoing the timing. I used a small flat head screw driver to feel the piston come all the way to the top. Took out the old cam and replaced it and set the timing marks on the cam at tdc. Checked the piston again and all lines up perfect. Adjusted the valves intake 003 and exhaust 004. Compression seems good but if you crank it, it is smooth till you apply gas and it hits the tdc positon and just wont pass that point without a stuggle. To much gas. Got it running and it idled well but pull the thotel and it still will not go past 1/2 way and it bogs if you press pedle any farther, same as the new carb did. I am sure it is something simple and just cant figure it out. I took the plug out and tested it again. Spark is white and (blue near plug plug) I noticed it is also drawing fuel from the primer at times. It is not backfiring at all so the timing must not be the issue. I think it is either getting too much fuel or air. Not sure which. Had to turn the idle screw out a long way to get it to idle smooth. I put in a new screw I got today in a rebuild kit. Where can you get a carb kit for a mikuni that was the original carb?? It is the one with the flat top not the pointed type carb. I noticed this time I got it running there was smoke coming off it but thought it was just the oil and spray I was using around the head. Only ran it a couple min and had to leave. |
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#78
06-22-2012, 07:23 PM
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man aint that a beoch. Go through all that and nothing changes. I have a feeling when you figure it out your going to kick yourself in the butt becouse its probably going to be something simple. To bad your not local I bet a socond pair of eyes would come in handy. Did you do away with the original choke? Did you put the old manifold back on? I think its still carb related. When you get it running (if you put the primer on) pinch off the fuel line from the primer and see if makes a differance. I'll see if I can find a kit and let you know
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#79
06-22-2012, 07:47 PM
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Heres one for a Howhit engine (thats what you got) but theres not much to it if the bowls not leaking and the float and needle isnt bad this kit aint going to help much imo
http://www.*************/item/Carbure...ne-06419A-6149 |
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#80
06-22-2012, 08:02 PM
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I did away with the manual choke on the orig carb which I am back to trying. Guess there was nothing wrong with it to begin with. I am using the new manifold and used a couple of nuts in place of washer so I could get it screwed down tight. I am sure if the timing was off a tooth it would not make much difference. I had to play with the chain to get the thing timed right on so the came and piston lined up exactly. Could there be a bad gasket somewhere that is letting in air?? Last week when it ran well all of a sudden it went back to 1/2 throtle and can't seem to get it back to normal
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#82
06-22-2012, 08:31 PM
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Did you do the wd40 trick
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#83
06-22-2012, 08:32 PM
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Quote:
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#85
06-24-2012, 06:20 PM
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I tried the wd40 and quick start and nothing happened but very hard to start and ran bad.
Put the original carb back on and now it is atleast running again. Re did the valves at intake 002 and ex 003 and still the same thing. Idles and bogs at 1/2 peddle. It runs better with the old carb. I tried the wd40 test again with the old carb and it dies down. It seems to be leaking around the new intake manifold. I made a gasket, tightened real good and still the same when I spray. The new manifold does not sit as high as the original, a good 1/2 or shorter on the bottom. Maybe I will put the old manifold back on and try again. I think I am in the right area of what the probem is....valves and timing and leaks. Seems to have good compression because when trying to start it, if it has too much gas will not turn past tdc...just goes back and forth. Then wait a minute and try again and it turns over well again. Still have to play with the mixture screw and idle screw to start it. Would the valve clearance on the cuv be differnet than a buggy engine.. ? The new manifold I bought was for a gy6 but it is shorter. Is the howhit difference from the regular gy6. Also the new dc CDI does not work on my atv. I should have junked it in the first place when it did not run. I see they are still selling this chinese junk scooters with the same engine for 749.00 I guess you get what you pay for. This thing was 3500.00 new at Tractor Supply and I see now they have a new one there for 7400.00 and it is another chinese piece of junk. It goes to show nothing that comes out of china is any good. Even my new carb says japan standard on the side, OH YA as if the means anything. |
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#87
06-24-2012, 07:35 PM
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I bought a used one (90cc not running) and got it running pretty easily and the wife wouldn't let us keep it!!! it appeared well built and it ran strong after the repairs- If that helps!!
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#88
06-24-2012, 08:22 PM
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I just ordered a new cylinder head with new valves and springs etc. Hope that is not hard to install. It has over 3000 hrs on the clock, and it was on 40.00 for a new one.
maybe that is why the manifold is leaking eventhough the opening looks good but the screws are getting messed up from taking the manifold of and on so many times. God only knows what the valves look like. I also changed the oil again today to see if heavier oil would work and used rotella 15/40 that I read on a post somewhere. That damn oil plug is a pain and replaced it also since the old one fell apart due to white metal fatigue...aka junk metal. |
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#89
06-25-2012, 05:26 PM
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Larry you have 321 hours not 3210 the last diget (the red one) is 1/10 of an hour
Analog or Electromechanical Hour Meter- This type consists of numbered wheels that revolve to show the running hours and tenths, comparable to those analog car odometers. They are usually the preferred choice when it comes to reliability and accuracy because in the event of a power outage, they will continue to display the data, and they are also built for tracking the data over an extensive period of time. |
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#90
06-25-2012, 05:45 PM
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OH I wondered. Mine does not have a red number. It only has 3 numbers all white and
says 310 and then on the face of the clock says x10, So I thought it 3100. I know we used it a lot when it worked. I was down at the pool today and friends of mine have a cart with the same engine but a lot more stuff. It is a howhit and they say theirs is hard to start also especially when it is cold but runs good. Everyone keeps saying there is a leak in the intake carb area so will work on that later this week. agian thanks for all the great info and help |
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#91
06-25-2012, 07:04 PM
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did you spray the wd while the motor is running? It needs to be running to tell if it makes a differance in the way it runs. Spray all around the intake at the head and carb get it good and wet if there is a leak you will know. Btw these howhit motors have a big valve head on them and gy6 motors have 2 differant types of heads. one is taller than the other. Good luck
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#92
06-26-2012, 01:26 PM
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I did the wd40 and the moter started to die....so there is a leak.....the head i ordered from BMI is for the rover/scout which I have the scout. A new head couldnt hurt and now
I have almost a complete set of extra parts. Dont know how i will get this leak solved. The intake is real tight on both ends. Maybe gasket cement all over both ends might do it. |
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#93
06-27-2012, 07:13 PM
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Today I sealed all around the manifold and carb and have no leaks. Is it possible something else is leaking? I have closed of all the openings in the carb but the air intake hole for the fuel bowl. Someone said to get and electric fuel pump? I am just lost
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#94
06-27-2012, 10:04 PM
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Mine had a split in the vacuum line at the fuel pump. its worth a look
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#96
06-28-2012, 12:44 AM
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Have you reworked the carb.
I also have had carbs.that had pin holes in body.When you spray the wd40 do you use the little red tube instead of spray.This will help find a leak by point of spray.
__________________
[SIGPIC] Take What You Have and Build What You Need
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#97
06-28-2012, 05:30 PM
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Ok I did the wd40 thing and nothing. Now is it possible it is not getting enough AIR??
When I have it at 1/2 peddle I have pushed the primer to give some more gas and it dies...so no enough air coming in. I have the air filter off while i am working on it. or could it be valves? |
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#98
06-29-2012, 08:32 AM
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Just woke up and thought I wonder if wasps has built a nest somewhere up in the exhaust and that is why this is happening. I took a bottle brush and cleaned the tail pipe but wonder if there is a restriction farther up? Will take of the exhaust today and see if there is a way to clean out the upper pipe and muffler.
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#99
06-29-2012, 05:23 PM
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Took off the exhaust and cleaned it all out. Check the timing again and realized it was backward opposite of tdc so reset the cam and tapets etc. got it to idle and start better but still no power. Sprayed the wd40 and just get smoke coming off the head.
so atleast it starts and runs on the flat area....so I give up and trying to figure it out. The valves are at 3 and 4 and wonder if they are the problem |
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