88 2pg runs poorly even after rebuild, etc. aaauuuggh!

[rib33024]

it will run, it just won't have any power, If there is any doubt in your mind, remove the exhaust pipe, and look into the cylinder with a flashlight. Rotate the engine by hand and if you see ports in the piston you have found your problem.

[clovold]

It ran pretty fast in reverse for a while, I was probably doing over 15mph in reverse, which was interesting...

There really isn't any doubt in my mind, but I will probably check anyway.

[Dave Box]

If your seals come out that easily then maybe the mating faces on the crankcase are worn and allowing for an air gap. This could be borne out by the fact that the cart runs well in reverse as the crankshaft is trying to twist the seals in the opposite direction and tightening the seal.
If it were my cart I would get some new seals and lubricate the rubber with two cycle oil and run a bead of Loctite blue around the out metal circumference.

Dave

[clovold]

The seals are brand new and pretty tight. These would not come out without a lot of force from behind.

I hate to loctite the seals in because they would be much harder to get out if I ever need to. It would feel like band-aiding the symptom when I should really find the problem.

[BrewCityMusic]

Could be off here BUT when I did my first 2PG rebuild, I put the rings in upside down (one of them at least) and had the exact same symptoms until I put them right- if You had to struggle or screw around at ALL to get the piston back into the jug when You did the rebuild this could be another potential issue (which again, fits the symptoms) ...

And just for fun, my 2 cents is on using the Loctite too - I'd rather have a PITA 2-4 years down the road when I have to replace them (which Loctite really won't be much of at that point) than the consistant, real and present PITA of blowing them out right and left (or front and rear as the case may be) which seems to be haunting You ...

[BrewCityMusic]

(oops, forgot my theory to back it) Rings in wrong, cold rings slide OK with enough compression to run, rings and jug get hot, rings start to bind, prohibiting running and possibly causing pressure issues in crankcase blowing seal(s) out ... Rings in the RIGHT way, all fixed.

[kyerik]

I agree with Brew, if the rings were in right, the compression would be much higher (closer to 145psi), even if the piston was turned around backwards.

Have you tried a new spark plug? Is the old plug wet with gas?

Are you mixing the gas or using the automatic oiler? Was the old jug scored up like it ran without oil?

[clovold]

Old jug looked great, not scored at all old rings looked great. I made sure to get the rings rotated properly in regards to the notch slot. Compression tester may be crap, though.

But, now I feel like a complete moron. I had no idea that rings had a top and bottom. I guess that gives me a 75% chance that at least one of them is wrong.

How do you tell?

[clovold]

Never mind, I found the PDF. Crap. I wish I would have known that before.

[BrewCityMusic]

Sorry to be the bearer, Amigo ...

Also (yep, there's more) a bad jug doesn't always show scoring, etc - but it quite often is out of round as the rings wear unevenly because the piston only hinges/tilts on a single plane (due to a single pivot point, the wrist pin) - replacing the piston and rings in that case won't help much, as the new round peg still won't seal correctly in an oval hole (hence boring the cylinder or replacing it in a rebuild)

Let's hope it's a simple upside-down thing