G2 runs on choke-only

[pachanga90]

Hey Guys,Moms' Cart is driving me up a wall!!!It was only running on choke,so I changed the filter,new gas,cleaned the carb completely,inspected and cleaned fuel-pump,even swapped the pump,adjusted the valves(.004),new plug,compression 160psi.It runs a lot better,but only on choke!!!I'm stumped!!!!

[1989Marathon]

If it was running good prior to this... clean the carb again. Also, make sure you have a good seal between the carb and the jug.

[Honorstick]

I know you're much more experienced than I with these things but did you make sure you don't have any air leaks around the air box and such? It doesn't seem to take much of a leak for these Yamaha's to act strange. Just a thought.

[pachanga90]

Its' got a brand new intake-adapter between the head and carb.That was cracked,I assumed that and the dirty carb were the issue,wrong!!We picked the cart up 2yrs ago,it never ran 100%,but it ran good enough to drive the little bit that they use it.We have our big picnic this weekend,and Kims' Mom wants to ride with us.Momma ain't happy,Noone is happy!!

[smallblock450sl]

I agree with Honorstick, sounds like the airbox isn't sealed. Try running it with the air box hose disconnected from the carb.

[pachanga90]

I tried every different combo with the intake...No filter, no air-box, Filter and lid only,etc...Tonite I swapped the carb with a new one Dad had,same problem.Put the old carb back on,I pulled the air-filter,put the box together minus filter,and it ran fine.My only conclusion is that the last time I did that was with the original fuel-pump,which was weak,so I had multiple issues.Mom drove it home,Shes' Happy,and The Original Pachanga-Lift Cart will be in the woods at the Picnic!!!

[Honorstick]

Cool! Glad you got it figured out.

[xobon]

been following this as a friends cart I am working on has the same problem. The one I am working on runs considerably better with the airbox removed but not perfect, I hadn't tried with no filter. Are you saying that you left the air filter out all together? or did I miss something? running without isn't really an option for me as this guy uses it on a farm, and it gets really muddy/dusty.

[pachanga90]

Yes,I removed the filter.No,I wouldn't leave it like that.I'm waiting on a new one.My Boss has the same cart,same problem,I called him and he was gonna pull the filter and see what happens on his as well.My only concern is that there is still an underlying issue,since the filter is pretty clean,even between the pleats.You can hold it up and see lite thru it easily too.I'm wondering if it has a valve-seating issue.I put 50psi in the cylinder,and didn't hear any leaks,but maybe the valve face is seating on a very thin margin,that doesn't seal as good hot,or with more restriction on the intake.If this works out for now,I'll pull it down later and go thru it.It smokes a little anyway.Thanks for the input guys!!!

[Mike Mac]

If its valve seal, compression wouldn't be that high. How old is gas?