Robin 295 Engine pops on lower RPM's

[vfret]

Im working on a 2002 EZ-GO that has a Robin EH29C 295cc motor that pops at the lower RPM'S or just off Idle. Sometimes it will hesitate, pop and then take off with no other problems. the popping only seems to happen when starting from a stop. The carbs been removed, soaked, cleaned. Iv replaced the coil, plugs, plug wires, fuel filter. Iv also adjusted the pedal height and throttle cable / switch as specified in the factory manual. The pilot screw is adjusted out 1.5 turns and the governor spring has been adjusted to the factory spec of 1-3/4". The valves have been adjusted to .004 at the cam while cold. It ran really poor before I performed the above services. Now it seems to run very well accept for a few pops on the low end. It also seems to accelerate very well and then at top speed seems to slow down a couple of miles per hour but will hold that speed. Seems to run strong during acceleration. I ran a compression test on both cylinders and got 60 PSi from each hole. While I was driving it I used a stethoscope to listen to the intake because that's where the pops seem to be coming from. The stethoscope confirmed that. I seem to be missing something here. Possible the compression s too low. Does anyone know what it's supposed to be and can anyone shed light on the low end pops?

[ez go go]

I can't believe it's running at all with 60 psi compression.. If your valves are adjusted properly, it's gonna have to have a rebuild... Comp that low only says it's time for ring replacement or more... You should be seeing some oil inside your breather cover with comp that low... Blow by will be pushing it in the breather..

[roady89]

Compression may be low because the valves are toast. Those twins are notorious for bad intake valves. Pull the rocker cover and see if the valve stem height is much different between intake and exhaust. Intakes are usually the ones to crap out. If intake stem is higher than the exhaust, your valves are bad. (I'm talking a definite visual difference, not with a mic or caliper) Another tattle tale is the adjustment screws are way out compared to the others. That's really the only way I know how to tell without pulling the head. Worth a quick check. If valves are good, like previous poster said. I'm surprised its running.

[vfret]

You still never mentioned what the Compression is supposed to be. It runs quite well most of the time. Just a little popping sound now and then ,I don't see any oil due to excessive blow by. I did adjust the valves, They were way off. Ill check the valve stem height. But I would like to know what the compression should be. Also, where's the best place to get the rebuild kits. Iv see everything from a complete kit including cranks, rods and slugs and just about everything else. to just basic kits. Iv considered purchasing a complete motor from rebuilt to new at around $2300 but not sure what the best way i.e quality would be. I can rebuild it myself but I think I would rather have it done by someone that is familiar with these little motors. The kits are around 1300 for OEM parts combined with the 800 to 900 Im going to charge to rebuild it it might be better off just buying a new motor . If anyone can give me some advice I would greatly appreciate it.

[SRDCOMPOSITES]

I just got a rebuild kit ordered for under 400 without crank. I'll send you the link. What year do you have. You could also call motors and more in GA. they do exchange with rebuilt ones for the 295 is $600 plus shipping of 65. You will have shipping of yours to them too but it's buil with warranty

[ldj1002]

Like mentioned it shouldn't run at 60lb. Did you check compression correct? Both plugs out, good battery to spin fast and the throttle wide open. If you mashed throttle just enough to turn motor you will get a false reading. If that throttle isn't wide open you can't get enough air into the cylinder to compress. My guess it your compression is a lot better than 60lb.

[StoveBolt]

Read through this thread, consensus is to adjust the valves hot.

http://www.buggiesgonewild.com/ezgo-...djustment.html

[ez go go]

Acceptable compression as far as running is concerned is about 120-150 or maybe a little higher in some cases. Remove both plugs and install comp gauge. Depress pedal fully and let comp needle top out and repeat at least twice on both cylinders... If your under 100 psi, then a rebuild is in order.. As far as kits, if the crank is not damaged, then check cylinder specs and go from there.. Scuffing the cylinder walls, rings and pistons may be all you need.. Then again a bore and oversize piston may be in order if specs require it. Also, check the intake valves for mushrooming and look at the cam condition for flattened spots on the lobes.