Engine Rebuild

[Eddie]

Looks like I am going to rebuild the engine in my YM1700, either broke or stuck ring. I am hoping there is no damage to piston sleeve. I will have the head reworked and checked at an automotive machine shop. What do you think about this parts list? Anything else I need to look at?


2ea 724450-22500 Rings
2ea 124450-23300 Rod Bearings
1ea 124450-01330 Head Gasket
1ea 124450-01750 Oil Pan Gasket
1ea 124450-11310 Bonnet Gasket
4ea 124460-11340 Valve Stem Seal
4ea 124450-11170 Valve Guide
1ea 124450-11680 Gasket
2ea 23414-1000000 Copper Washer 10


Thanks
Eddie

 

[elarson]

Just my .02, but if it were me I would invest some diagnostic time into this before ordering a trunkload of parts. I f you have gotten to the point that you are certain that the engine is no longer serviceable, a teardown is in order before an accurate assessment of parts need can be made. It also depends on what you are looking to accomplish. The list of parts shown doesn't address the crankshaft, and couldn't really be called a rebuild. If a repair is all you need, it may take even fewer parts than shown. Give it an internal look first.

 

[Eddie]

What kind of diagnostics do you suggest. How do you diagnose a broke or stuck oil ring except looking at it, I'm open to suggestions. I don't think the lower end of the engine needs any work. It carries 35psi oil pressure even hot and at low rpms. The engine still runs good has good power, it just puffs blue smoke and uses access oil. When idling it puffs blue like maybe it's only on one piston. I'm hoping there's no damage to sleeves, if so I'll replace them when I get into it.

 

[larso1]

Your parts list looks pretty complete. You may not need the valve guides, although they could also be your problem. Some guys also recommend replacing the rod bolts (big end) and the head bolts since they can stretch. I would definitely do a compression or leak-down test first to confirm the bad rings. A compression gage with 500 to 600 psi full scale minimum would be required for the compression test and a threaded adapter fitting into an injector hole (may need to be madeup by a machine shop) or into a glow plug hole if so equipped. Just my 2-cents.

Bill in CO

 

[Eddie]

If the compression rings were good and I had a broke or stuck oil ring, would a leak down test tell me this????

 

[normde2001]

A leakdown test would show any ring problem, causing air escaping out the crankcase vent. In any case I would not be in too big a hurry to tear it down. If you do not find an obvious problem, a disassembled engine is awfully hard to troubleshoot.

 

[Ozarker]

I always replace rod bolts.............cheap insurance.

 

[Eddie]

Well I got the engine torn down, everythings looks real good, no wear groves at top of sleeves. Just looks like the rings are worn out. Took one of the oil rings off the pistons and placed it in the cylinder and have a 1/4 inch gap left.

 

[Jagmandave]

!/4" gap? looks like you found the source of your oil usage.....

 

[Eddie]

Look Maw, NO SMOKE.

It's all back together running and mowing with it. It don't smoke at all. So I guess the rings were absolutely worn out.
It was very easy to start. I spun it a few times without compression and as soon as I turned the compression it fired off. It got a new air filter, new fuel filter, new radiator cap and water pump. My wife walked by and said your seat looks just like new, that's because it is. It also got some suitcase weights for the front end because I've been using a 5' Bush Hog brand finish mower, very heavy, at times I would have to guide with brakes, but I've been doing that all my life with tractors. It handles like a different tractor now.

The water pump is worth the money!!!!! I was mowing where it would normally run 220-225 degrees and it would only run 180. This was with enough antifreeze to protect it thru the winter. I'm a happy Camper!!!!!!! /forums/images/graemlins/cool.gif /forums/images/graemlins/cool.gif /forums/images/graemlins/cool.gif /forums/images/graemlins/cool.gif