How do I diagnosis a head gasket issue Kohler Command 18 Hp

[Gulkanariver]

I have a 2004 Toro Z Master model # 74162 mower. It has an 18 HP Kohler Command single cylinder engine model number CV 493S Spec #27529. I have 570 hours on the mower. How do I check for a blown head gasket.
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[BigFish]

Well, if it's not running, or was smoking like a big dog, just pull the head off......it ain't gonna fix itself.

But I digress............

I use a cyl leakdown tester, but you can check it with just an air blowgun.
Pull the valve cover.
Bring the piston up TDC on compression stroke, hold the flywheel/crank securely( however you wanna do it) and push a little air in the spark plug hole, and listen for air in the pushrod galley and/or all around the outside of the head.
The Slapper, AKA Mr. Kohler, might be able to offer up some ideas...........

[Gulkanariver]

I bought the mower about a month ago for $500. Only has 570 hours on it. The guy I bought it from said it may have a blown head gasket. I've cut my grass a couple of times with it. It may not have as much power as I expected but it still cuts. The oil that drips from the valve cover onto the exhaust may have made him believe it had a blown head gasket.
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[Landrus2]

Originally Posted by Gulkanariver

I have a 2004 Toro Z Master model # 74162 mower. It has an 18 HP Kohler Command single cylinder engine model number CV 493S Spec #27529. I have 570 hours on the mower. How do I check for a blown head gasket.
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Compression text will give a good idea or a leak down text.

[Gulkanariver]

I'm going to do a compression test on Saturday. What would be a good compression number for this engine?

[piston slapper]

Originally Posted by Gulkanariver

I'm going to do a compression test on Saturday. What would be a good compression number for this engine?

I'm sure it has an ACR so your compression readings will probably be 100 to 120...
A few questions...
Does the engine smoke ?
Is the sparkplug fouled ?
How much oil does it use or leak ?
Does the engine make a hissing noise..like air brakes..when you shut it off ?
Is your oil level too high ? Smell like gas ?

[Roger]

I had a leaking head gasket on a Kohler Pro Command, 15hp. Here is the thread, complete with pics on the replacement of the gasket. Your engine may be similar.

http://www.lawnsite.com/showthread.php?t=334950

[Gulkanariver]

I've only used it a couple of times but:
The engine does not smoke.
The oil is not over filled.
The oil does not smell like gas.
I haven't run it enough to foul the plug.
From what I can tell it looks like about a tablespoon of oil will leak out of the bottom of the valve cover over two weeks.
The engine does not make a hissing sound.
I don't believe I have a head gasket problem. I think someone miss diagnosed the oil leak at the valve cover. I'm going to do the compression test in the morning and not worry about it if the compression is at 100-120.

[Gulkanariver]

Compression is about 118. I'm going to service the mower, fix the oil leak at the valve cover and cut grass. Thank you for all the help.

[piston slapper]

Originally Posted by Gulkanariver

Compression is about 118. I'm going to service the mower, fix the oil leak at the valve cover and cut grass. Thank you for all the help.

The valve cover bends pretty easy....new replacement about $20...
Check the engine rpms....