# Strange Oil Problem



## Itsalwayssomething (Jun 10, 2020)

About a year ago I bought a G16 Gravely at a state auction. Paid $200. Before i bought it i could tell the engine was a basketcase. When I got it home and took it apart it had 2 holes in the block, both connecting rods were broken. It took me about 6 months to find all the parts i needed, including a new block, and got it all back together. Ran great did some mowing put about 20 hours on it. Slowly it started to loose power with an occasional backfire. 
After starting one morning i noticed that the left exhaust was dripping oil. Pulled the plug it was soaked with oil. Cleaned it, checked to see if it would fire, fired fine. Put it in started it up left exhaust was not getting hot. 
I figured it might be the valve stem seal was leaking oil into the cylinder. Even though the seal was new I pulled the head and found a good bit of oil in the cylinder. Cleaned it up replaced the valve stem seal, new headgasket, and put it back together. 
Started up and ran on two cylinders for about 2 minutes. Pulled the plug and it was oil soaked again. 
Engine has new pistons and rings, had the cylingers honed, did a compression test 115 pounds on each cylinder. 
I am scratching my head here, any suggestions?


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## TonsOfGuns (May 10, 2020)

Do a leak down test instead. Find out where the breach is


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## Itsalwayssomething (Jun 10, 2020)

thanks i will give it a try


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## Itsalwayssomething (Jun 10, 2020)

Itsalwayssomething said:


> thanks i will give it a try


Leakdown test showed about 8% leakage leakage, and both cylinders were just the same????


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## Bob Driver (Nov 1, 2017)

Kohler M18??


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## Itsalwayssomething (Jun 10, 2020)

Yes Kohler M18


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## Bob Driver (Nov 1, 2017)

Were you mowing across a slope with the left cylinder low?


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## Itsalwayssomething (Jun 10, 2020)

No I live near Charleston SC, there are no slopes, but it did this running on my barn concrete floor. Anyway i was reading the kohler manual and the only thing i did not do was after the overhaul i used 10W-30 mobile 1 oil in the engine. And i have it filled to the top mark. Manual calls for straight 30 weight in this climate. Tomorrow I will drain the oil and refill with straight 30 weight only 1/2 way on the dipstick. Maybe it has too much oil in it. If that does not work I will pull the Jug off and take a look.


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## Itsalwayssomething (Jun 10, 2020)

Changed the oil and lowered the oil level, no help there, I pulled the jug off took the piston off the rod, took the piston out examined the rings everything looked normal. then I noticed that the gaps in the oil rings and the joint of the expander were all lined up and at the bottom of the piston. This may have been the whole problem. I moved the joint in the expander to the top of the piston and made sure that the oil ring gaps were 180 degrees apart 90 degrees from the expander joint. I will put it back together in the morning.


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## TX MX5200 (May 12, 2020)

That sounds like you found the issue...good find too


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## Itsalwayssomething (Jun 10, 2020)

Got it back together, fired it up ran good on both cylinders, mufler got hot smoked like the devel for about 15 minutes until all the oil burned out. Cut grass in the field for about 3 hours so I would say problem solved.


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## SoldierJohn (Jun 11, 2020)

Happy days, good ending and good old fashioned engineering problem solving.


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