150 cc not running
 

bought a 150cc for the kids last Christmas they ran the hell out of it, then one day their friend was driving and when she stopped it looked like she threw it in reverse while it was going forward. A puff of smoke came out of the exhaust and it has never started again.
Gets spark, won't fire with starting fluid in head,
spark looked a little week so put in new plug and coil
has compression not guaged it yet
thinking the timming key pin is broke, will check timming, valve gap, and compression. While im at it I will clean the stater.

any ideas?

You need to actually measure the compression to know for sure. Could be a major clue.

You are on the right path with checking the timing. I'd be surprised if the coil went bad. Be sure to report back what you find. This is good info for others.

Well, it looks like the timing is off.
I lined up the mark with the TF and the cam sprocket is off about 10 teeth. The chain is tight.
Where is this key pin that might have slipped? Anyone have a picture
I read a thread about a guy with the same problem a few months ago but I can’t find it now

Pull the right side fan cover, than fan, remove the nut with an impact gun. Next you will need a flywheel puller to pull the flywheel, but if the key way stripped you may be able to remove using a steering wheel puller, but be carefull not to pull out the threads. If you need a puller give mre a call. I'm out of them currently but have them on order and should have them shortly.

Tom

some of my freinds do the same

I ordered a flywheel puller from Scooter Parts Place and paid 17 bucks extra for 3 day shipping, still no puller and they will not return my e-mails.
I used paypal and have filed a claim.
Used a steering wheel puller and pulled the threads out, metal is too thin.
Anyone know who might have one in the Houston area ?

I have some on order but am looking hopefully at next week, provided the supplier gets them in by weeks end as promised. I had a customer that could not find one either so I lent him mine, so I don't have one to even lend to you. If you have no luck contact me next week and hopefully I will have them in. Tom

If one had a lot of time on his hands they could make one with the correct size bolt, use a drill press and drill a hole in the middle of the bolt
Weld a nut on the top of the bolt and screw a smaller bolt thru it

I think I’ll order one from someone else and wait for the mail again

This is the one I have:

http://cgi.ebay.com/ebaymotors/Flywh...Q5fAccessories

i like your price but Taipei, Taiwan
does it have to go thru customs ?

got my money back from paypal and a 27mm x 1" reverse thread puller from someone else

the thing comes off real easy with thre right tools
only problem is the key pin was fine.

I was told to line up the timming gear with the two little holes even with the head and the T on the timming mark ????

no slack in the chain, I don't think it jumped any teeth.

OK
Here are pictures of the timming sprocket with the small holes even with the head and where the timming mark ends up

Attachment 971

Attachment 972

BTW
the compression is 50 psi
the timming chain is tight, but the engine was heated up pretty good.
Do you think the chain could have jumped any teeth, or is this how the timming should be ???

i don't use the timing marks at all-pull the plug put a straw in hole bring up to tdc that
way-you can remark your flywheel if you want[its probaly marked wrong] now reset your
valves if your motor was heated up it tightens up the valves.then run it or check the compression again on my gy6 irun 160#-but you probaly will be fine @120# to 130#

Looking at the pics timming should be right on. You say the woodruf key is in tact. Now you say you only have 50psi comprssion. Don't know how you took compression. The proper way is to turn engine over 5 revolutions with a well charged battery and throttle in full open position. A closed throttle will give much lower numbers since you are restricting air intake, bot you still should have more than 50psi. Next step is to determine the loss of compression. If not already done bring engine to TDC and make sure both valves are in the closed position, heel of both lobes facing up, visual of the valve springs are equal in height. Next put 3-4 squirts of engine oil in cylinder then do another compression test noting any changes in compression. If the compression rises you have a ring problem,( oil seals the rings) if no change this indicated valves or a flattened cam intake lobe. Keep us posted.

Tom

Not looking so very good here !
at full thottle I get 60psi
with some thin gun oil I get 90psi for a few revolutions.

is there any way to do the rings without taking the whole damn thing apart ?
it only has 125 miles on it

I set the valves to 10mm but it didn't help

I will pull the head and take a look-see

:crying:

I know BuggyMaster said to do the compression, but the auto parts wanted $60 for the tester that I may never use again.
I found one at HarborFreight for $20

When you pull the head off the cylinder will just pull off. Do you have any oil on the plug? What brand buggy do you have?

Tom

it's the carbide 150cc
no oil on the plug

so I can just pull off head and slide it back over the new rings with the ring compressor tool ?

that sounds too easy... lol

Yes, I don't even use a ring compressor. Since the bottom of the sleeve is beveled I just lightly push down on the cylinder using a tiny screwdriver to push the ring in the groove while pushing and rocking the cylinder at the same time, one ring at a time. You just have to take your time and work slowly.

Tom

do you have the 59mm Big Bore Kit in stock ?
would I have to change the carb also ?
or
what about just a replacement piston and ring set.

I have both in stock, and no you would still use your exhisting carb with a possible rejet. If you give me a call I can give you more specifics. (662) 301-1563

Tom

Check to see if the motor key has sheard off. Happened once to me it would turn over and try to start but the place where they key should have been had actually moved .3". Letting it turn over but never start.

been there done that
it is the rings:mad:

Have you pulled it apart yet?

Tom

not yet
I just order this
http://cgi.ebay.com/ebaymotors/ws/eB...m=160539145148
hope its the right part

If your buggy is one of the brands listed you should be OK but remember you get what you pay for. If I were to order 100 cylinders from China it would cost more than what you are paying. No returns?

Tom

Thats what I say about my wife - " you get what you pay for" no returns ! ....... lol

Hope the eBay part works for you. I would have went with tom myself, his parts are guarenteed! I could see it if it were a small part or something, but not a piston and jug kit. IMO.

I will let you know how it turns out.

E-Bay parts came yesterday- Hey, they are not plastic...

I will put them in this weekend and let yall know the compression.

Attachment 975

The kit looks good!!! Plastic... that was funny. Why does the box say GY6 125? if they brag about 150cc.

I thought the same, but it has 150 cast on the cylinder.
The piston is 57.32mm without the rings

How did the kit work out.

Tom

I put the new piston kit in today, here are some pictures

Attachment 976

Attachment 977

Attachment 978

Attachment 979

I have 148 psi compression now :hooaray:

have carb problems after sitting up for 6+ months
stopped the flooding problem by cleaning the float jet. Now starts and idle fine, but as soon as you give it gas it dies.

Time to start researching carb cleaning.

What threw me off was the timming mark, everywhere I read it said to line up the mark on the flywheel and the cam holes.
Here is a picture of my new flywheel mark @ TDC.

Fuel, Spark, Compression

Attachment 980

:hooaray::hooaray::hooaray::hooaray:

Took carb completely apart this time and cleaned everything. Put it back on and it still acted up. Pulled out the air/fuel cap by drilling a self tapping screw in the edge. Screwed it all the way in then out 1-1/2 times, put the air box on and it runs fine now.


BEFORE :(
Attachment 983



AFTER :)
Attachment 984


THANKS FOR THE HELP GUYS:biggthumpup:

:lol: :lol: Those before and after pics are hillarious!

Glad you are good to go.

I just went back and looked at what all you did in this thread. What an accomplishment! Great job with great reference pics!

Hey you have the rear view mirror I need, want to sale it? If not who has one? I also need one of your rear fenders.

I should have a rear view mirror. Give me a call. (662-301-1563)

TOM

Dang I wish I knew that i would have called you this morning,. I just ordered a rear view mirror off the net for it at 6:00 this morning.