BuggyMasters.Com - An On Line Mini Buggy Forum and Go Kart Forum

Go Back   BuggyMasters.Com - An On Line Mini Buggy Forum and Go Kart Forum > Technical Discussions > 150cc GY6 and Under Engine Tech

150cc GY6 and Under Engine Tech GY6 and Smaller Technical Discussion Forum

 
 
Thread Tools
  #1  
Old 06-12-2012, 12:05 PM
shane92 shane92 is offline
Lurker
 

Join Date: Jun 2012
Location: belltown,pa area
Posts: 7
Default the valve timing is backwards

i have a carter talon with a gy6 engine. the motor sounds like it has no compression and i just replaced the base and head gasket. when i turned it over it was blowing gas out the side of the carb. i thing the intake valve is opening on the exit stroke, but i dont now how to fix it.
  #2  
Old 06-12-2012, 04:05 PM
chuckorlando chuckorlando is offline
Contributor
 

Join Date: Apr 2010
Posts: 356
Default

Forget all about timing, flywheel marks, and top dead center. I say this as I've uilt no less than 10gy6 engines and seen at least 3 with bad marks

Now here what ya do. Take the cam out and lets start fresh.

1) Take a straw and put it on the plug hole.

2) Turn the fkywheel till the piston is all the way up. ALL THE WAY

3) Now just set the cam in with the big hole pointing up. Both small holes and the line should be in relation to the head.

4)Put the timing chain on. Now your set.

If for some reason it's still more than a tooth off, chances are the cam gear was pressed on wrong. I've seen that to

Some guy's will say follow the manual with the marks. I ask this " what do you do when the marks are wrong"
  #3  
Old 06-13-2012, 05:54 PM
shane92 shane92 is offline
Lurker
 

Join Date: Jun 2012
Location: belltown,pa area
Posts: 7
Default

i did that but gas is still coming back throw the carb. and when i went to turn it over the starter did not kick off i had to unhook the battery. but when i did that it didn't do it agian.
  #4  
Old 06-13-2012, 05:58 PM
chuckorlando chuckorlando is offline
Contributor
 

Join Date: Apr 2010
Posts: 356
Default

Are you positive your floats are not sticking allowing it to flood over just a hair? Like I said it's possible the gears pressed on wrong but not very common. Valves adjusted?
  #5  
Old 06-13-2012, 06:09 PM
shane92 shane92 is offline
Lurker
 

Join Date: Jun 2012
Location: belltown,pa area
Posts: 7
Default

it looks like the gas is not being sucked in to the engine it is blowing the gas out were the filter box goes. it only does it when the motor is turned over
  #6  
Old 06-13-2012, 07:32 PM
shane92 shane92 is offline
Lurker
 

Join Date: Jun 2012
Location: belltown,pa area
Posts: 7
Default

the intake valve was bent
  #7  
Old 06-13-2012, 08:31 PM
chuckorlando chuckorlando is offline
Contributor
 

Join Date: Apr 2010
Posts: 356
Default

well that aint good
  #8  
Old 06-14-2012, 11:52 PM
shane92 shane92 is offline
Lurker
 

Join Date: Jun 2012
Location: belltown,pa area
Posts: 7
Default

now i found out the exhaust valve is bent too
  #9  
Old 06-15-2012, 05:39 AM
chuckorlando chuckorlando is offline
Contributor
 

Join Date: Apr 2010
Posts: 356
Default

If your timing was off that bad you likely hit them on the piston. Make sure nothing else is broke. I been there brother. On a brand new stroked engine, 4hr the valve dropped, Ruined everything.
  #10  
Old 06-18-2012, 07:16 PM
shane92 shane92 is offline
Lurker
 

Join Date: Jun 2012
Location: belltown,pa area
Posts: 7
Default

i got the new valves and it is running but now it is leaking oil really bad out of the new head gasket and it is blowing dark gray smoke out the exhaust.
  #11  
Old 06-19-2012, 06:28 AM
kliff's Avatar
kliff kliff is offline
Contributor
 

Join Date: Mar 2010
Location: Grovetown, GA
Posts: 309
Default

If it is leaking oil out of the new head hasket, chances are you didn't get the surfaces clean, before re-assembly. Most often, you'll see black patches on the head and cylinder surface. These can be several thousandths thick, and should be cleaned off. They are a burned on varnish like residue, from the revious gasket. I use single edged razor blades, a lot of time and caution. Don't want to gouge the mating surface, or cut yourself. But these surces must be clean, then I use a scotch brite(fine) pad, 2" diameter in my die grinder to buff the surfaces clean. Again, carefull, don't wanna create any low spots the scotch brite can cause. THEN, on a piece of plate glass, 1'2" thick, with some 600 grit paper and wd-40, I surface sand both head and cylinder till they have FULL contact, and are "brite" all the way across. Time comsuming, and maybe a bit over the top for some, but gasket failures to date..ZERO. PS, spray both sides of your head gasket with a coverring coat of "Copper Coat" Gasket treatment. Use the aerosol, NOT the brush on kind. Available at all auto stores.

Dark gray smoke sounds like a mixture issue in the carb, but it could be leaking oil into the combustion chamber, as well as to the outside.
__________________
kliff
  #12  
Old 06-19-2012, 09:01 AM
shane92 shane92 is offline
Lurker
 

Join Date: Jun 2012
Location: belltown,pa area
Posts: 7
Default

i was thinking about getting a big bore kit and replacing it all
 


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 12:41 PM.


Powered by vBulletin® Version 3.8.3
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.