1995 ezgo no power with air filter

[Jrdale08]

1995 ezgo. New plugs, fresh gas, new air filter, good spark from coils, carb cleaned. Runs cold, once warm has no power with air filter on. Runs good if you take the air filter off. Has after market muffler on it. What am I missing?

[cgtech]

Well, since your in the yamaha gas section, let me just suggest this... you should have just bought a yamaha instead.

But, since your stuck with an ezgo, "runs better with air after off" leads me to think "too much fuel" is the problem. (Less restricted airflow to match the fuel being delivered). What exactly do you mean by "aftermarket muffler"? Is it a dirt bike muffler welded on your exhaust pipe?

Also, a 1995 would likely be a Robin 2-cylinder, have you ever checked/set the valve lash?
Its a super common problem, and if you tried and "ran out of adjustment", you got issues. Ever checked the compression? ("Low compression" can often be fixed on that particular engine by fixing the poor valve adjustment, but that could be signs of trouble that "valve adjust" cant fix).

I really love how smooth that engine runs, but, when it goes bad, it goes real bad. ($). I have "fought" with those before on "totally screwed" ones that ran, but never ran good. Check compression, set the valves, check compression again..& see how it goes. or just buy stupid china carbs 4 or 5 times (JK, never buy those). If your compression is "90" after a good valve adjust, your wasting your time to think its gonna be a good runner. (I dont know the PSI spec from the manual, I'm sure it's over 130, but I know garbage is garbage). I'll go look in the manual stash for a more exact number.

[Jrdale08]

Well we adjusted the valves. They were a little loose. Adjusted to .004-.005. Checked compression and have 90-100 each cylinder. Is it a possibility timing is off or should we skip to the next step; rebuild top end with new rings and pistons?

[cgtech]

90-100 is horrible.

[slonomo]

Rebuild time

[CP241]

Cgtech

He is spot on about everything. 100psi is awful. I'm surprised it will run at all. Should be 160-170psi on a good running engine. It needs to come out and apart. Once you get things measured you can decide what to do with it from there.

[Jrdale08]

Thanks for input. Still puzzled by how well it runs without air cleaner on. We will tear it down and access the damages.

[trig123]

Originally Posted by Jrdale08

Thanks for input. Still puzzled by how well it runs without air cleaner on. We will tear it down and access the damages.

Did you check the compression with throttle held wide open ? or maybe use another tester ?


I have rebuilt a few of these engines and yet to have put a new piston in unless it is damaged. I had rather have the OEM if it has them than one of these after market ones. Test that compression again making sure you hold that throttle all the way open and make sure you tester is working correct.

Some of these older air boxes had a small opening on bottom that sometimes would get stopped up with mud. Just something to check.

If it runs as good as you say it does and don't smoke then I might check more before pulling that engine.

I can't see an engine with only 100 pounds of compression running good.

Seems strange that it runs good with the air box off. It may indeed need rebuilding but I always like to double check things before I go tearing to an engine

[mozzer]

Did you install a standard airbox & filter? maybe it was tuned to run with a k and n style filter. The fact it has a modded exhaust would suggest somebody was tuning for more power.

Sent from my SM-G950W using Tapatalk

[ThomasBachi]

Same problem a year ago. Stumble across the answer by swapping a carb last year. I Replace the carburetor new runs with the filter on now.
Ps I cleaned the carb with a fine tooth comb.
G@@d Luck