# Kohler 14hp OHV intermittent white smoke



## manderson0404 (Feb 24, 2013)

Hello everyone,

I picked up a Snapper sr140 with a kohler cv14 14hp ohv engine. When I start the engine I get a lot of white smoke from the muffler (and i think under the muffler). It will lessen then go away entirely after a few minutes but returns again after a few more minutes. This will continue as long as I use it. 

This is my first small engine and I am excited about learning how to work on them, hopefully with some help from you all  

I have replaced the gas with new gas, and changed the oil and oil filter. When I changed the oil there was some small streaks of white, but for the most part the oil looked ok.

Can anyone advise me on my next move?

Thanks,
Michael Anderson


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## 30yearTech (Sep 14, 2006)

May have a leaking head gasket, causing pressure to build in crankcase and oil to feed out breather and into carburetor.


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## manderson0404 (Feb 24, 2013)

hey! thanks for your reply. 

I have one more question though. A friend of mine thought it could be the piston rings, and I wondered is there a way I can decided if it is the head gasket vs the piston rings? I was going to change them both after looking at the service manual, but then I saw those rings are like 80 dollars!


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## 30yearTech (Sep 14, 2006)

A leak down test could provide a little insight, but unless there has been some dirt ingestion (like being run without an air filter or a very dirty one), then I doubt it's the rings. Pulling the head would allow for inspection of the head gasket and the cylinder and piston as well.


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## manderson0404 (Feb 24, 2013)

I will pull off the head and replace the gasket then and let you know. 

Thanks much


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## paulr44 (Oct 14, 2008)

30yearTech said:


> A leak down test could provide a little insight, but unless there has been some dirt ingestion (like being run without an air filter or a very dirty one), then I doubt it's the rings. Pulling the head would allow for inspection of the head gasket and the cylinder and piston as well.


A name-brand leak-down tester is not cheap, a Harbor-Freight one is like $35. That's the only way to determine your answer. You must be able to block the engine so it can't rotate and have it at TDC on compression stroke to do the test (and you'll need a compressor).

Two things I'll add...you don't tell us the age of the engine.
First, a change was made to the Command series piston rings to help reduce smoking on start-up. They did this a long time ago.
Second, graphite head gaskets erode naturally over time. I did head gaskets on a Kohler twin, 10 years old which was pushing oil. It only had 150 hrs. on it (just broken in) as the tractor was only used for pushing snow.

We're assuming the unit isn't parked on a grade, the oil level isn't overfilled, and you're using the correct weight oil.


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## manderson0404 (Feb 24, 2013)

Hello again. I've been waiting on the parts to come in before I checked back so I'm sorry I have no responded. 

I don't for know the age of the engine for sure. I bought this used, but from digging around I think this was made in 91 or 92. 


I started taking apart engine today for the head gasket replacement, and I pulled the spark plug. I compared it to some pictures I found online, and I think it would appear to be oil fouled. I took a couple pictures just to get some opinions here. 

So again, doing some research an oil fouled plugged means it probably isn't the head gasket (I'm still planning to replace it since I bought it already) but means it is either the rings or the valves right?

If it is the valves should I be able to see the damage, or can it be invisible but still causing problems?


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## paulr44 (Oct 14, 2008)

QUOTE: "So again, doing some research an oil fouled plugged means it probably isn't the head gasket (I'm still planning to replace it since I bought it already) but means it is either the rings or the valves right?"

On an OHV engine a blown (leaking) head gasket can most definitely allow oil to migrate into the combustion chamber. The push-rod chamber is next to the combustion chamber, as well as oil return galleys. So there's couple of oil sources via a failed head gasket for oil to creep in.

Also, a flat head engine with good rings, but a bad intake valve guide can oil foul a plug...like 30yr says in his footer..."Ya gotta know how it WORKS, before you can figure out why it WONT." An OHV with a bad intake valve guide can also oil foul a plug.

An engine is a pump. A pump with combustion, but a pump. When the piston goes down, CC pressure is developed. A faulty CC breather can also make for oil control issues...I've seen air filter housings fill up with oil (guess where that goes...the combustion chamber via the intake!) due to a bad CC breather.

So, just because an engine oil-fouls plugs is not necessarily indicative of bad rings. The plug fouling is the symptom, not the disease. The disease can sometimes be tricky to find, but as I've demonstrated can be from a number of sources.


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## manderson0404 (Feb 24, 2013)

I'm going to post some links to some pictures next post, but I have to get 5 post first


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## manderson0404 (Feb 24, 2013)

Ok First up. Here is the gasket I removed from the head. I have never seen one of these before, but it looks ok to me. Just thought I would get a second opinion though. 
https://dl.dropbox.com/u/5497417/OEMGasketFront.jpg
https://dl.dropbox.com/u/5497417/OEMGasketBack.jpg

I also replaced the breather reed. This is the old one, and again, to my untrained eye it looks OK, but I welcome those more knowledgeable than I. 
https://dl.dropbox.com/u/5497417/OEMReedFront.jpg
https://dl.dropbox.com/u/5497417/OEMReedBack.jpg

The valves looked pretty awful to me, and I was advised I needed to clean them up. 
Before: https://dl.dropbox.com/u/5497417/valves.jpg
After: 
https://dl.dropbox.com/u/5497417/exhustvalve.jpg
https://dl.dropbox.com/u/5497417/Intakevalve.jpg

Do those looks clean enough to you all? Should I do more? 

Lastly, Paulr44 mentioned _CC breather_. Just to make sure I am on the same page, a CC breather issue involves that reed I replaced right? CC means combustion chamber, not crank case? I included a picture of the top of the head, and the breather reed is under that gold metallic object that is reflecting the light so bad.
https://dl.dropbox.com/u/5497417/Head.jpg


So looking at the post, I still need to check/replace the intake valve guide? Anything else I should look at before I crack the engine inhalf to get into the crank case?

Thanks!


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## 30yearTech (Sep 14, 2006)

The head gasket you removed does indeed look good and does not look like it was leaking. What is the condition of the cylinder walls?


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## manderson0404 (Feb 24, 2013)

The piston is about half way down in the cylinder, and I don't have any great pictures, but I think it looked ok. I did take this picture right after I took the head off.
https://dl.dropbox.com/u/5497417/piston%20walls.jpg


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## paulr44 (Oct 14, 2008)

CC stands for crankcase.
A breather has a reed, but some have a valve akin to a poppet like B&S.
A clogged breather that won't allow air to escape can cause oil control problems too.
A crankcase vacuum test (while running) or leak-down test can help identify a plugged breather.

It's hard to see in your pic, but it looks like there's next to no cross-hatch left, and the top ring is very visible. If you can elaborate it'd help. If you can rock the piston a lot, it would tend to indicate wear is an issue.
I agree with 30yr., the head gasket isn't that bad however you can see what I mean by erosion when you look at the perimeter of the combustion chamber.

Reed valves sometimes crack, but almost never wear out normally. They do wear out from lack of proper maint. as dirty oil gets dirt, an abrasive, on the reed which is a moving part.

GIVEN WHAT you're showing and telling us, I would suggest you pull the valves (at least the intake) and check the stem for wear. If there's a step in the stem between where it rides in the guide and the area exposed to the intake port, it's seen dirt ingestion. Put a touch of oil on the stem and lightly grasp with and run your index finger and thumb tips up and down the stem...it's more accurate than you think.
Valve stem wear is a good indicator of the health of the piston, rings and cylinder.
BUT not always...I've seen cylinders hold up ok with worn out rings from "rapid" dirt ingestion, rather than modest or slow dirt ingestion over time.


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