View Full Version : Will your Kohler V-twin do this?

10-23-2003, 11:45 PM
I was looking to buy a mower with a 25hp Kohler Command (horiz. crankshaft) with just at 1300hrs on it. It cranks perfect and quick with a little choke, immediately turn off choke she idles perfect and smooth. Stab the throttle, sounds great and still perfectly smooth. Not a hint of smoke at any speed ever. BUT, remove the oil dipstick while it's running and a mist of oil is coming out, same thing if you remove the oil fill cap at the valve cover - is this normal on these engines? I always thought this meant bad rings and, thus excessive blowby but this engine seems perfect otherwise. Try your Kohler, does it do the same thing? I have no idea if this mower actually uses oil, I didn't get to mow with it yet, just ran it sitting for 15-20 minutes. What should I think about this?

Envy Lawn Service
10-23-2003, 11:52 PM
I think that's normal :confused:

I have never did that because I assumed that is what would happen.

One indication you may want to check is the plugs. Pull them and take a look. Then put them back, crank up and run full throttle a while. Then do a clean shutoff, pull plugs and inspect again.

10-24-2003, 12:15 AM
Lol.....you are kidding,right? The motor is fine. Here's a hint to check for a good ignition land. Remove the plug and reconnect it to the boot.Hold the end of the spark plug and start the motor. After doing this,report to us as to what kind of spark you have. :-)

10-24-2003, 12:16 AM
:laugh: :laugh: :laugh: :laugh:

Sorry, but that was funny

10-24-2003, 12:25 AM
The blowout mist is normal. That mist is what keeps the rocker arms lubed. The push rods are solid on a Kohler, unlike an auto engine that uses hollow push rods and oil flow from the lifters to lube the rocker arms.

10-24-2003, 12:32 AM
Just noticed the other day the pressure on a 23 horse while opening the oil fill cap. I'd say it's normal.

10-24-2003, 07:34 AM
Kohler motors have a pressurized crank case. When you take of the fill cap, oil should come out with the motor running.


10-24-2003, 10:13 AM
Thanks for the responses. ZX12R and deason, I am confused by your responses... EJK2352,dvmcmrhp52 and firefighter - glad you have noticed what I see is normal. I have never had any experiences with these Kohler's or any motor with a pressurized crankcase that I can recall. Growing up working on cars and heavy equipment I was always taught that this "blowby" meant worn rings and to avoid the engine. Never thought of the Kohler needing the oil mist to lube the rocker arms. Let me tell you I bet it does a good job. I had this motor just barely off idle, pulled the dipstick and there was a good mist of oil coming out. This sure eases my mind about this motor. It sures goes against my teaching but that fact that it doesn't smoke one bit made me think I was wrong and I should ask those who knew.

10-24-2003, 10:53 AM
Not sure why you would remove the oil stick while the engine is running...they do use a pressurized oil system.. have two smaller 16 hp Kohlers, one on a 8 year old machine...it does eat oil and is a little finicky to start on cold mornings, but it's earned it's keep,; when it gives up the ghost, I'll make a planter out of it and repace it with another one...

10-24-2003, 11:02 AM
GardenTech, I removed the dipstick while running because I was checking for blowby. Like I stated, I didn't know these engines had a pressurized crankcase at the time. Thus my "test" proved worthless but it isn't uncommon to see people remove oil dipstick, oil fill caps, etc. while an engine is running to check for blowby. Thanks.

10-24-2003, 05:52 PM
being a mechanic most engines auto and equipment will do this.its normal and its a good thing.if it didn't do this then i would start to worry about your oil pressure and cylinder pressure