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rbig
06-04-2005, 05:29 PM
I have a John Deere 400 with 60" deck. I had to take it to a temporary job at our church 3 acre site while the church mower is being fixed in a shop. There are lots of ditches, ruts, culverts, etc that I mow through. When my tractor tilts going up or down a ditch, or is sideways on a slope during a turnout, I get oil smoking until the quantity that got in the cylinders on the slope burns out, especially if the oil level is full or slightly over.

The question I have is how the oil is getting from the crankcase/pan area into the combustion chamber? What is the path being followed when I'm on a slope surface?

Restrorob
06-04-2005, 06:52 PM
I have a John Deere 400 with 60" deck. I had to take it to a temporary job at our church 3 acre site while the church mower is being fixed in a shop. There are lots of ditches, ruts, culverts, etc that I mow through. When my tractor tilts going up or down a ditch, or is sideways on a slope during a turnout, I get oil smoking until the quantity that got in the cylinders on the slope burns out, especially if the oil level is full or slightly over.

The question I have is how the oil is getting from the crankcase/pan area into the combustion chamber? What is the path being followed when I'm on a slope surface?


You asked a engine related question and didn't say what engine is on your unit ? post model and spec. numbers that would be helpful !!!

rbig
06-04-2005, 07:46 PM
Well, I was thinking in general. But specifically, it's a Kohler K-532

Dirty Water
06-04-2005, 09:37 PM
I don't know your engine in question, or work that many small engines period, but my first thought was a failed PCV system.

An Engines PCV system allows crankcase pressure to vent out back into the intake tract and be burned up again, if your on a slope, I'd imagine oil is getting past the PCV valve and being fed back through the carb.

Of course, This is from a guy who worked on car engines.

EDIT: Are you sure its oil being burned and not excessive fuel? (Oil will be blue, fuel will be black).

When you turn a carb on its side, its going to dump tons of fuel into the cylinder.

Restrorob
06-04-2005, 10:26 PM
Well, I was thinking in general. But specifically, it's a Kohler K-532


I studied the break-down of your engine and the only thing I can come up with is possibly when the engine is sitting sideways the oil is running into the cylinder and when the piston comes down its acting as a plunger and forcing the oil past the rings possibly through the ring end gaps. OR the oil in the valve spring ports is not draining because the return port is higher than the valve stem and being sucked through worn valve guides.

This is in deed a good one !

rbig
06-04-2005, 10:55 PM
I'll check the pcv valve. Thanks.

Wow! Here I am assuming my engine has a pcv valve. Think it does, but not sure. Anyway, I'll find out.

Restrorob
06-04-2005, 11:12 PM
I'll check the pcv valve. Thanks.

Wow! Here I am assuming my engine has a pcv valve. Think it does, but not sure. Anyway, I'll find out.


This engine doesn't have a pcv valve !
But even if it did it would smoke all the time !
I was a Automotive Service Technican for 12yrs. before changing professions.

Smalltimer1
06-05-2005, 02:25 AM
It does sound like a ring issue.

Dirty Water
06-05-2005, 02:51 AM
This engine doesn't have a pcv valve !
But even if it did it would smoke all the time !
I was a Automotive Service Technican for 12yrs. before changing professions.

I was just throwing out suggestions :)

Your worn valve guides suggestion intrigues me, but I think if they were that worn, it would smoke all the time.

Probably is a ring issue. Whats the hours on the engine?

Restrorob
06-05-2005, 08:30 AM
I was just throwing out suggestions :)

Your worn valve guides suggestion intrigues me, but I think if they were that worn, it would smoke all the time.

Probably is a ring issue. Whats the hours on the engine?


Well the worn guide suggestion is only when he's on a slope like he said,The hot thin oil could be sucked through the intake guide when it puddles around the valve stem,See no stem seals on this one.
Kohler hasn't made this engine for many years,Thus assuming this is probably a high hour unit.
This is how I based my (suggestions) only.

wushaw
06-05-2005, 05:44 PM
When I mowed with my little Hustler fastrack with a 15hp Kohler for the first time it did the same thing on a slope, I check the oil and it was a hair over full. After that first mow it has not done it since but the oil level dropped to the full mark after that first mow also.
I have had the unit for 1 1/2 months and has had its first oil change and still no problems with oil in combustion chamber.

I would make sure your oil level is at or just a little under the full mark and try it on your slopes and see if that helps.

rbig
06-07-2005, 12:33 AM
It's a low hour engine because of rebuild a year ago. And, it's oil smoke. It only smokes when I cross a ditch or get sideways on a slope. Clears right up after the intitial smoke cloud. This suggests not a ring or valve guide problem, or smoke would be continous. Runs great other than when tilted.

Restrorob
06-07-2005, 08:13 AM
It's a low hour engine because of rebuild a year ago. And, it's oil smoke. It only smokes when I cross a ditch or get sideways on a slope. Clears right up after the intitial smoke cloud. This suggests not a ring or valve guide problem, or smoke would be continous. Runs great other than when tilted.

Unless somebody is pouring oil down the carb. thats the only sources for oil to enter the combustion chamber that I can think of.
How do we know the rebuild was done properly,We don't.
Looks like your gonna put up with your smoke cloud.

Oldtimer
06-08-2005, 08:22 AM
How much slope?

What weight oil are you using?

Check the oil very closely and don't over fill it.

If the engine doesn't smoke on level ground then is ok.