Kohler engine

[Dean85]

Kohler Courage xt173 0084 smart choke system. Takes several pulls to start, even warm it can take several pulls to get it started. I have replaced the carb with no change. A leakdown test shows that air is getting into the crankcase. Piston is at TDC and the oil is not overfull. When running, oil spits out the breather tube once and a while. Are the rings bad or is it possible for the internal part of the headgasket to be bad, allowing air to be forced into the push rod area into the crankcase. I picked this mower up pretty cheap due to what I thought was a carb issue, as the seller could not get it to run. I found that the idle jet was obstructed. It runs fine when it starts with no smoking.
Thanks

 

[jhellwig]

Originally Posted By: Dean85
A leakdown test shows that air is getting into the crankcase.


Leakdown tests only mater on 2 stroke engine.

Check the pcv valve and do a compression test.

 

[bchannell]

Originally Posted By: jhellwig
Originally Posted By: Dean85
A leakdown test shows that air is getting into the crankcase.


Leakdown tests only mater on 2 stroke engine.

Check the pcv valve and do a compression test.


Whaaaaat? You bet a leakdown test is for 4 cycle engines. A leakdown test will tell if a piston ring is worn, valves are not seated, head gasket blown etc.

It very well could have a blown head gasket, allowing air to pass into the crankcase, this would also explain the oil fromt he breather.

 

[Dean85]

It absolutely is for a 4-stroke engines. It will determine if valves, rings or head gasket is leaking. It is alot easier to do a leakdown test on a 4 stroke vs a 2 srtoke.
I did not detect any air leaking from the valves and the engine is pretty new with no oil burning, so I doubt the rings are bad. The part of the head gasket that seperates the cylinder from the push rod gally is pretty narrow, so I am pretty sure that part of it is leaking, pressurizing the crankcase and spitting oil out of the breather tube. May also be the cause of it taking several pulls to start it. I can tell if oil is coming out of the breather tube after a few minutes as it starts to surge due to oil being sucked into the carb. It did not do this at all after using it for about 25 minutes today.

 

[jeepman3071]

If you replaced the carb and it is taking that many pulls to start, I would definitely pull the head.

I've had two cases with the same issue on those kohlers. One was a damaged head gasket, the other a valve seat.

 

[jhellwig]

Originally Posted By: bchannell
Whaaaaat? You bet a leakdown test is for 4 cycle engines. A leakdown test will tell if a piston ring is worn, valves are not seated, head gasket blown etc.


That is what I would call a compression test. To me a leak down test is where you block the intake and exhaust on a 2 stroke and use a vacuum pump to check for leaks.

After looking I see what you guys are referring to as a leak down test. I was wrong.

 

[Dean85]

Head gasket was fine and no warping of the head. I did notice a little trail of oil on the cylinder wall when moving the piston up and down. Cylinder walls still have the cross hatch marks. I lapped the valves, reassembled and used it with no operating issues. It took a few less pulls to get it started.

 

[jeepman3071]

I'm on my work machine, so I can't look up what this Kohler looks like. Is it an OHV engine? If so, make sure the valves are adjusted to spec. That can certainly cause issues as well, and I've seen it on many Briggs engines as well as the Chinese Honda clone engines.

 

[Dean85]

It is an OHV. I have set the valves at .005.