Engine Sputter

Your digital camera.

Well that only works if this 20 year old lawn mower hasn't already been re-assembled incorrectly. Which at this point I'm kinda wondering about.

Ok so last time I took it apart, I ended up mangling up one of the springs pretty good trying to reinstall it. It ran even worse after that. So I bought a new one for $4 on amazon and installed it today. The mower runs MUCH better now! It still runs like garbage when it's cold. But once it warms up, it runs much nicer, and at a much higher RPM than before. To be honest, it may even run worse now when it's cold. But the tradeoff is it runs better than it ever has since I've owned it, when it's warm.

These higher RPMs have brought back an old problem that had gone away... oil seems to leak out of the base of the filler tube, where it meets the block. It's not a fast leak... but its fast enough. And i'm sure some level of dirt is going in too. I don't think this is the cause of my problem, it's just a fresh new problem. The seal seems ok, I'm tempted to go to the hardware store and get an additional O ring and jam it in there to force a good deal. But then I got to thinking, a "regular" O ring might melt or burn from the heat?

Yes they are N buta regular O rings are neorpene.
About $ 2 from any mower shop.

Oil leak is fixed. I took the top off the mower, reseated the correct O ring, got some locking washers, the kind that grip, and re-bolted the top back on. No more flop or wobble, and the oil filler is now squished down firmly so no more oil leaks.


Now its just the engine issue. It really feels like the problem is TOTALLY different now than when I started this thread. The sounds are nothing like the movies any more. Now my inexperienced ear says it kinda just sounds like it is misfiring. Would that make sense? It does it less and less, the longer it runs. After 10-15 minutes, it barely does it at all. I don't know anything about it, so I suppose it could still be fuel delivery. But if it were a fuel flow problem, wouldn't it have been less of a problem when the mower was running at lower RPMs, and more of a problem at the new higher RPMs? Plus if it were a fuel delivery problem, what would cause the problem to go away once the engine heats up? What creates the spark that goes to the spark plug? Is it possible whatever that is, is bad on this mower?

You probably have done this already, my LT is so slow this morning I didn't read all posts. Have you run cleaner through the engine (Seafoam)? If not it is worth a try.

I've run so much seafoam through there, when you take parts of the carb apart, they are laughably clean. This spring, I even ran maybe 1/4 of a tank of about 50-50 gas seafoam mix. Which should be too strong to even start an engine like this but I got lucky. Before that, for like 2 years, I've been running it with a "normal" amount of seafoam in the gas. It hasn't ever seemed to have any effect at all.

Compression check?

*S*S*S*S*S*SOOOOOOLD!!!!!
Sold the mower today for $85. Out of my life thank god!!

I am still curious why it ran crappy while cold, if anyone has any thoughts? Would a compression problem go away when the engine warms up? What would a compression problem mean, what would be the actual "problem" that needs to be repaired?