Outdoor Power Equipment (Lawn Mowers, Snow Blowers, Chain Saws and more) Discussions

I have an HH60 engine on a 1981 or so Troy bilt tiller. It ran fine for years but the summer broke a rod. (I think it was low on oil). I have taken the engine apart. No gouges in the sylinder or holes anywhere. There is a small ridge at the top of the cylinder that you can barely scratch a fingernail on. I put the old piston and rings in and my hand over the top of the cylinder. It seems to have alot of suction/compression when pulling the piston from the bottom.

There is aluminum on the crankshaft . I will try the muratic acid trick I have read elsewhere on here.

Question is, is this worth rebuilding? I like tinkering with stiff but money is a conern. I like this motor because it has electric start on it. ROds are expenesive as the one for my model number says it is 40 bucks.

Should I re-ring it? I have a cylinder hone from harbor freight I bought the other day. I have never used one. I dont have a ridge reamer but might be bale to rent one at Autozone.

It ran well before this happened except now that I recall a week or so before it went, faint white smoke cam out of the exhaust when it was reved up.

ANy advice? Do I need to mike everythign out to an automobile's engine precision or since this is a tiller just clean the crank, bolt a new rod and rings and go with it?

I have been takign off parts and cleaning them. The head did seem to have alot of carbon but was easily cleaned.

I think it may have been rebuilt before as the engine paint is oversprayed in places. The piston was stammped STD which I assumes means it is stadard sized.

Thanks again!

My early 1980's Troybilt Horse just recently gave up it's engine - it was a 5HP Tecumseh hh50 - I don't know if it had been replaced in the past or not since I bought it used. Instead of trying to rebuild it right away I purchased a new Tecumseh HH60 from smallenginewarehouse for $199 with free shipping. Their websight said it would fit excet for the end crankshaft bolt which is 5/16 x 24 on the new engine, the old one was 3/8 x 24 tpi. So far everything is as they said. My only concern is that the reverse pulley that mounts on the very end of the crankshaft has a 3/8 in mounting hole. I have been trying to find a 3/8" to 5/16" sholder bolt to solve this problem to no avail. Everyting seems as though it will go together OK, so for now, I think I will bolt everything together and just try not to use reverse yet. My only option for the 3/8 to 5/16 bolt problem is to have a machinist to make me one since I am sure of what I need. If anyone else has had this problem and found an answer please post.

Thanks...

I have a 1979 TroyBilt Horse with a HH 60-105106F. With a lot of research, I've found that Pats Small Engine seems to have more parts available with very reasonable prices. Shipping is usually within just a few days. Here is their link: http://www.psep.biz/index.htm There are a few issues that you may find out regarding this motor. 1) Depending on your specific model, a new crankshaft may not be available, nor are undersized rods. 2) Some people have had some bad luck with replacement / aftermarket rods. This comes together with a simple solution: If your crank is scored or out of round, it will need to be welded and re-machined. I have not had any bad luck with the aftermarket rod, as long as the crank is within spec. The bearing clearance for the rod is only .001 - .002" and if it is in spec in one way, but not in another, you will have wear problems and the rod will not last, regardless of who made it. If a new crank is available for your engine, it will cost you approx. $120, or possibly $100 for a good used one. But I like to use what came originally, so for mine, I went to a reputable crank repair shop, had the rod journal welded and re-machined to the proper spec. I have built many engines over the years for cars, boats, snowmobiles, etc., and many in racing applications. I have NEVER had a welded and re-machined journal EVER go bad on me yet.... EVER! The cost should be about $100 give or take, and you should have a shop in your area, so you don't have to worry about shipping. The other advantage that you have in doing this is that you KNOW that you have a part that fits, and nothing will be different. In finding a crank repair shop to do this, you may have to check around some. Some automotive shops may not be set up to repair a crank of this size. But if you check around, I'm sure you will find a shop that can take care of your crank. Another area of concern is the piston. Replacement pistons are available in standard size, + .010, and + .020 oversize, so make sure you have your cylinder checked for wear with a proper bore gage. You may only need to hone the cylinder for proper seating of the rings. One more small detail that many people seem to miss out on is the oil they use. These engines were designed to run with SAE 30 "NON-DETERGENT" OIL. Never, and I mean NEVER use anything else. Do not make the mistake of using auto engine oil, this is a good way to ruin your rings or rod bearing. All in all, you can completely rebuild your engine for $200 or less, which is considerably less expensive than buying a new engine and having it adapted to your machine. My engine lasted over 30 years originally, before breaking a rod. With a properly rebuilt engine, you can expect to get another 30 plus years of service from it. After a rebuild, you may need to adjust your carburetor again. Over the years of your engine's service, and with the ensuing wear on the motor, your carb may have needed to be adjusted for YOUR machine to run well. After a rebuild, you should go back to the original carb settings to start, and then make any minor adjustments necessary. If you love to tinker and work with engines, as I do, you'll have some fun with this motor. Happy Wrenching.