1. Ms5242 Manual Engine

I recently acquired a Honda HR214 lawn mower with a GXV120 engine. It is unknown how long it sat unused. When I got it, the engine was stuck, but by giving a socket wrench a little nudge on the flywheel nut, it broke free. The motor started easily, and after warming it up, I put in new 10W-40 oil as directed by the operator's manual. I have removed and cleaned the carb. This one has the rubber breather tube that just press fits into a hole on the side of the engine. There is no sign of oil leakage around the oil fill tube where it meets the engine block.

Problem is, it smokes badly for several minutes after start up, and in fact, spits droplets of oil from the muffler when it's cold. The smoking lessens, but never completely goes away after the engine warms up. Suggestions I've received as to what the problem is have been, 1. Rust had formed on the inside of the cast iron cylinder, thus causing the 'stuck' piston which is now scraped off and causing scratches on the cylinder lining. Worn valve guides. I'm not having any luck finding a shop manual for this engine to get the specs on it.

Professional advice and a manual would sure be helpful. Thanks Cheese.

I read your suggestions to ahencman last year when he was asking pretty much the same things about his. He posted an experiment he did with Restore. Social guide for class 9. I haven't been able to find a way to contact him directly to find out if he replaced the rings on his, but did find pictures on flicker that he took apparently during his tear down. I've done a fair amount of work on small motors, but never torn one down to replace rings. Wish me luck. Oh, and I may be back to ask more questions as I go, if that would be alright.

Ms5242 Manual Engine

O.K., I pulled the head off of my motor. It actually sort of fell off when I pulled the last bolt out. That, to me, was sort of strange because I've never had a gasket seal give up that easily.

What I noticed then is signs that the gasket was not properly sealed, and oil was getting into the cylinder from the oil channels passed the gasket, and not the rings. There were all sorts of signs that oil was being blown to the outside of the engine passed the gasket as well. The cylinder walls still show signs of cross hatching, and no overt scoring of any kind. I'm going to try replacing the head gasket first before tearing the engine down any further, and see what happens.

My question then, what is the proper torque for the head bolts, and is there a sealer that should be applied to the gasket before reinstalling it? Sounds like you need rings. I don't know what Honda recommends, but I like a ring gap of.010' or so, not more than.020' for the compression rings. Valve guides are very unlikely to cause large amounts of smoke. You can wiggle the valve back and forth when it's open to see if there is much play, but I have never seen a worn valve guide cause a significant smoking problem in a small engine in my years of working on them. The cross hatch pattern is consistent with hondas. That's why I say they generally take well to a ring job because the engines don't wear out, just the rings.

The scoring on the rod sounds like it has been run low on oil before. You might look into purchasing a rod as well. Check the crankshaft for wear just to be sure. On Japanese engines, yes this is probably similar to what happens to a majority of them when they get used long enough to smoke. On domestic engines, except maybe the kohler command single cylinder engines, there is usually more wear on other internal parts by the time the rings are worn out.

Sometimes all they need is rings, but often they also have worn rods and the briggs singles commonly have a lot of wear on the balancer (rider engines) by the time the rings are worn out. Domestic walk behind engines almost always have cylinder damage when they start smoking.

Most of them have aluminum cylinder walls and most japanese engines have cast iron cylinder walls. There are plenty of exceptions to the rule, but this is usually pretty accurate in my experience.