I have an older scag sthm 61" with a cv22 kohler command engine with about 1300 hours. . I have been fighting gremlins over the past years with it and getting by. The newest thing is that I was losing power and once I shut the pto off the engine reved right back up to speed. Now she is blowing blue smoke and eating oil like crazy. I took the plugs out and the left side was normal, but the right side was full of black crud and soot like stuff. I turned her over and e left side had good compression ( sucking my finger in and out) but the right side had notably less. I am assuming that there is excessive blow by on the right head and need a rebuild. Do they sell an engine rebuild kit? What am I looking at for cost? Is it worth the cost to have it overhauled?
Scag sthm engine eating oil
- Thread starter Morson82
- Start date
Ok. I did a compression test and the left side is around 100 and the right almost nothing. This is the plug with the crud on it from the right. I took off the valve cover and turned the engine over and both valves seem to be moving as they Should.
shiftsuper175607
Lawn Addict
- Joined
- Sep 11, 2013
- Threads
- 10
- Messages
- 1,000
Now that you have determined the spark plug looks good(joke)....and the valves are moving. You will have to take the head off as ilengine said to examine the head gasket.
Last edited:
Ok, pulled the head and one of the valve heads is broken, not sure if exhaust or intake. What's the best step from here? Total rebuild or just replace the bad parts? What else should I do or look for while I'm at this point Of disassembly?
shiftsuper175607
Lawn Addict
- Joined
- Sep 11, 2013
- Threads
- 10
- Messages
- 1,000
How does the cylinder bore look?
I would wire brush it and clean it up good to get a good look at every thing.
Disassemble just that head and valves and then go from there.
Check head for level...probably OK is the gasket appears to not been leaking.
Up date. I replaced the exhaust valve (lapped) and cleaned the head. I put the head back on (new head, intake, exhaust gaskets and head bolts) everything torqued to specs. Checked compression and I have 125 on each side. But now I can't get the mower to run. Turns over fine. Checked and there is spark. I tried putting some gas directly into the carb and the gas shot back out and actually stopped the engine from turning over momentarily and then it turned over. Is it a carb issue.? Not sure where to go from here. Really don't want to bring this to a repair place.