Kohler K series engine leaking tons of oil while running under load

[Alrashid2 355]

Here is what I have on my phone, let me know if this suffices !

 

Oil drain plug on bottom left side of photo 

[rmaynard 15,776]

That looks like a standard pan (4 pints).

[Alrashid2 355]

Thanks guys, looks like I have the correct oil fill then. 

 

1 hour ago, rmaynard said:

Let's see a picture of the oil pan.

 

The reed needs to be in the correct location. Plate gasket goes against the block. Breather plate against the gasket with the recessed part facing the block. Then the reed, followed by the baffle, the filter, the rubber seal, the other gasket and finally the cover with the vent hole up, just like the diagram shows.

 

Yup, unfortunately for me that is exactly how I have it together. Have had this apart 3 different times now, and just tore it apart yesterday and that is exactly as it is oriented. 

 

Anything else I can check that could be the cause, other than piston blowby? I'm debating doing a leak down test just to at least confirm what is happening, though I have no idea where to start. I could have sworn someone here posted a step by step with photos on how to do it, what PSI to look for, etc... but can't find it! Any alternative to a compressor for the test? Hand pump?

Edited January 7 by Alrashid2

[Alrashid2 355]

Just wanted to give a slight update. Had a chat with Lincoln over at AZ Tractor since I know he is experienced with these... he was very adamant that blowby from the piston rings would not cause oil to leak past gaskets. He said the Kohler engines will have oily, smoky exhaust so thick you can't even see through it far before the blowby causes oil leakage... He said if I'm not burning oil and no smoke, then he wouldn't be concerned with the rings at all. 

 

Curious what you guys think 

[oliver2-44 10,019]

6 hours ago, Alrashid2 said:

Any alternative to a compressor for the test? Hand pump?

Google YouTube Small engine leak down test.  

 If the spark plug stays fairly clean that will tell the story.   As long as the engines isn’t knocking or making noise run it and work it  for a while. 
 

I have a 1965 Case180 with the same 12hp engine. The cylinder measures .009 wear. That’s about 3x recommended wear It fouls a spark plug in about 30 minutes. Buts that’s all I need to take it to tractor shows.  Interestingly only very light smoke on throttle up and no breather oil just putting around shows.  But I bet it would smoke bad if I worked it hard. 
 

PS you had a thought about adding a vent to the top of the dip stick tube. The rod dipper splashes oil big time in the crankcase. If you want an oil bath pull your dipstick with the engine reved up. 

Edited January 7 by oliver2-44

[Mark siebenaler 112]

How deep is the oil pan is it like one inch deep or like 2 1/2 deep?

[Alrashid2 355]

@Mark siebenaler It is around 2 inches so I think 2 quarts is right.

 

@oliver2-44, that's what is so interesting with this engine! Full throttle, pull the dipstick tube, and I just feel a bit of air puffing out, no oil at all. Put a white paper towel over it and it is still clean... weird!

 

I have slept on this and came to the conclusion I am being a bit OCD about this engine, as I'm sure you can all admit you probably are sometimes too! I get like this with all my projects: rifle builds, home improvement jobs, my own Subaru, wood shop projects... in the end, I usually move onto something else to obsess over and realize the original problem that I stress about didn't matter all that much.

 

I'm thankful the engine runs otherwise perfectly for me, has no other issues, still gets the job done, and doesn't leak even more oil! I chatted with a friend at work who has various tractors too and he has one that will leave a trail of oil as it drives down the driveway! He has to top it off every 30 min! He has been running it this way for 20 years and has no intentions of fixing it. I think I am going to try to do the same, and if I happen upon a nice Kohler for a good price someday, maybe I'll think about swapping over and eventually learning to work on this one. 

 

Thanks guys!

[oliver2-44 10,019]

While you say you gaskets are in good condition, the camshaft cover gas is 40 years old.

Its inexpensive and easy to replace.  Next time you order parts get one and change it.

Better yet, buy a complete gasket set, which will give you a spare head gasket.  Their a lot cheaper that way.

I prefer the OEM kohler ones, get one where the head gasket has a "Fire Ring" which is a ring right around the inside of the cylinder bore.

While the Amazon sets are 1/3 the cost, some I've bought are OK and some paper thin.  Not worth the hassle.  

 

[Alrashid2 355]

Thanks @oliver2-44 I've actually already replaced all gaskets except the head gasket at this point. Oil pushing past new gaskets when under load. Guess I'll just have a dirty engine!

[Alrashid2 355]

Side question for you guys - anyone know how much oil it takes to go from the Add to Full lines on the dipstick? 

 

After rechecking, I now see that my oil moved about from the L in FULL to between the : and F on the dipstick after running for 1 hour under heavy load, and appearing to lose a lot of oil (but was just messy and really didn't lower it all that much it seems).

 

If this holds true, I could run another 3 hours before needing to top off, but I'm not sure how much oil would be in the crankcase at the ADD mark 

 

 

[OutdoorEnvy 1,678]

I would guess around 1/2 quart or so.  You could try running it not completely at the Full mark.  Maybe half way or less to the Full line, like in the Add word range and see if it leaks.  It might have like an 1/8-1/2 quart too much.  As long as you aren't below the Add line you should be safe to run it.  Just keep an eye on it more in case it burns a little bit.

[Alrashid2 355]

Thanks @OutdoorEnvy. I'll experiment with running it lower on oil, see if the blowback effects change at all. If not, then I rather run it slightly overfill just to avoid ever accidentally running it on low. 

[pfrederi 18,090]

You only fill it to the two dimples just to the left of the word full   (the word full should not be in the oil)

[Alrashid2 355]

Maybe I was running a hair overfilled then... didn't think it was that much higher though? Would that cause that much pressure? I guess she self-regulated down to the 2 dots at least!

 

Any of you guys ever heard of pouring a bit of Marvel Mystery Oil down the spark plug hole and letting it sit overnight? 

[RED-Z06 2,365]

My K181S was leaking oil everywhere...someone had put the breather on wrong and the reed was held shut.

 

https://youtube.com/shorts/YsHlivHShOs?si=M9fTA8Bv2ZaO4AZR

[Alrashid2 355]

Thanks @RED-Z06 - I'm going to tear the breather apart again and post photos and see what you guys think. Positive I have it put together correctly but who knows maybe it's getting stuck shut

 

Is the filter mesh absolutely necessary?seems like it just keeps oil from splattering.

[RED-Z06 2,365]

24 minutes ago, Alrashid2 said:

Thanks @RED-Z06 - I'm going to tear the breather apart again and post photos and see what you guys think. Positive I have it put together correctly but who knows maybe it's getting stuck shut

 

Is the filter mesh absolutely necessary?seems like it just keeps oil from splattering.

The filter lets oil mist condense and drip down into the bottom of the center cavity where the tiny drainback hole is.

[lynnmor 7,447]

On 1/7/2025 at 9:00 AM, Alrashid2 said:

@rmaynard does the actual reed itself only have one direction?

 

My engine does say AS on it though I think someone said that it was probably reworked by Kohler prior to being thrown on a wheel horse.

The A stands for special oil pan.

 

Download this manual for more information.  On page 1.4 it shows how to use the dipstick, but none is exactly like yours.  On page 1.5 it says that an A oil pan will take from 1 to 1.75 quarts.

Edited January 9 by lynnmor

[Handy Don 12,917]

8 minutes ago, RED-Z06 said:

The filter lets oil mist condense and drip down into the bottom of the center cavity where the tiny drainback hole is.

Clever! There had to be a good engineering reason ‘cause why else go through the trouble of having it.

[Alrashid2 355]

So I plowed again today! Didn't leak as much oil this time - it mostly came out of the Governor area and breather cover.

 

Im going to experiment with running Rotella T4 10w40 diesel oil and see if that helps lessen some of the blow by at least.

 

Curious about this though. I ran the engine at full throttle and pulled the dipstick. Air movement for sure but no oil spraying and the dipstick didn't go shooting...

When I placed the dipstick with the gasket barely touching the tube, it would suck back down tight! So I have air moving out but it is also moving back in and pulling vacuum... Is that normal, especially for an engine with bad rings?

[RED-Z06 2,365]

If it moves in and out but wants to pull the dipstick in, thats all working correctly, everything sounds normal in that regard. There is no governor shaft seal, youll get some moisture there.

[oliver2-44 10,019]

Even on the breather you have air moving in and out. 

When the piston goes up, the bottom side of it creates a vacuum in the crankcase and breather. When the piston comes down the bottom side of it creates a pressure in the crankcase and breather.

[Alrashid2 355]

28 minutes ago, oliver2-44 said:

Even on the breather you have air moving in and out. 

When the piston goes up, the bottom side of it creates a vacuum in the crankcase and breather. When the piston comes down the bottom side of it creates a pressure in the crankcase and breather.

Would that still be the case if I had bad rings?

[RED-Z06 2,365]

1 hour ago, Alrashid2 said:

Would that still be the case if I had bad rings?

Its about balance.  In a perfectly running fresh broken in engine of for example..34cubic inches, the piston will come down, displace 34ci of air volume out the breather, as the piston starts back up, the Reed valve snaps shut, sealing the crankcase and it falls under whatever vacuum negative 34ci of volume creates.  However you will always have blowby, on any piston engine, there will be blowby..so whatever volume of blowby you have will be evident at the breather at every power stroke.  0 blowby would mean the piston would come down under a full vacuum and equalize at bottom dead center, but obviously that never happens.  

 

A faulty reed can either not let blowby escape, building case pressure, or fail open..and let it both inhale and exhale air.

 

The earliest clean air standards required crancase air to be vented inside the air filter, prior to..crancase gasses and oil vapor were freely expelled out from the engine.

 

An engine with bad rings, cracked ring land, burnt piston, cylinder issues...will push combustion gasses into the crankcase, and often creates a powerful smoky breather effect 

[Alrashid2 355]

UPDATE!

 

Sorry guys, I have been sick with the flu all week so didn't get a chance to get back to you guys or even do much to the tractor.

 

Finally got sick and tired of being sick and tired and pushed myself to get back in the garage. I know blowby can't be fixed without an engine rebuild, but in the past I have been able to reduce it by using thicker oil. Likewise, I have seen cases with other small engines where the piston rings get suck and allow some blowby, and can sometimes be loosened back up. So, I did a few things:

 

1. I pulled the spark plug and using a plastic pipette, placed about half an ounce of Marvel Myster Oil on top of the cylinder. I let that soak overnight before starting the tractor. For the hell of it, I also poured 2 oz of MMO into my 2 gal fuel tank and ran that through after too (made the exhaust smell sweet!)
2. I drained my oil (10w30 basic Walmart brand oil) and replaced it with Rotella T4 15w40 diesel oil. I had read good things about the Rotella T4 with helping with blowby and burning oil, and likewise I think the 40w will help a bit with blowby at running temps.
3. While changing the oil, I drained the old oil into precise measuring cups and measured that, after all the oil I lost during my last plowing session, I still drained out 72 oz which is 2.25 quarts... that tells me I was definitely overfilled before. This time around, I filled with just 1.75 quarts of the Rotella T4 15w40 oil. This put me about halfway between the Add and Full marks.
4. Just to be safe, I pulled the carb and took apart the breather assembly. Everything was put together correctly, except that I noticed that one of the two gaskets was ripped. I doubt this would have caused my issues but I replaced the gasket with a new one. 

 

Well, today we got the most snow we've gotten since I bought my Wheel Horse - 4 inches! I plowed the driveway as I have and it performed beautifully. Once I was done, about an hour later, I parked her and popped the hood - NO OIL LEAKAGE! The engine face looked a bit wet but I believe that was just from snow hitting the engine and melting - wiping my finger it just felt damp, not oily. 

 

As far as I can tell, I had zero blowby or oil leakage during this session of plowing, with the engine under heavy load plowing uphill. I'm hoping that my "blowby" was really due to thin oil and being overfilled... but time will tell. I'm happy though!

 

 

 

 

Edited January 19 by Alrashid2