K181 how is this possible?

[RetroMower 349]

Yesterday I more or less finished restoration on my green tractor. I decided to stretch its legs so to my delight my wiring was correct and it fired right up and ran very well and I drove it for a few minutes. Upon its return to the garage to my horror i saw oil dripping profusely. While still running i looked for its source and was dumbfounded when i saw the dipstick flailing wildly. There was an impressive amount of air cycling out of the dipstick along with a lot of oil. I quickly shut it off. My question is how can it run so well with no hesitation or misfiring with such copious blowby? I put a compression tester on it and got around 60 psi. I never tested the compression on the two k241s I rebuilt for my horses but the scored pistons and burnt valves were enough that they were near impossible to start and would barely run when they did. I'm stumped 

[pacer 3,176]

My first thought was maybe gas has leaked into the crankcase and overfilled --- ck and see if it is diluted and smells of gas...

 

But, with only 60 psi on compression ?? that too could be the problem.... but again, with busted piston, etc it should run badly??? 

 

If not gas in oil, then youll prob need to pull the head  hmmmmm!

[RetroMower 349]

5 minutes ago, pacer said:

My first thought was maybe gas has leaked into the crankcase and overfilled --- ck and see if it is diluted and smells of gas...

 

But, with only 60 psi on compression ?? that too could be the problem.... but again, with busted piston, etc it should run badly??? 

 

If not gas in oil, then youll prob need to pull the head  hmmmmm!

I was thinking the same thing but I know there might already be gas in the fresh oil I put in there thanks to a brand new sediment bowl that doesn't shut the fuel off to the carb. How much oil does the crankcase hold? I cant rely on the dipstick as I think its mismatched because it makes contact with the oil pan. I added approximately 3/4 of a quart but this still wouldn't account for the chuffing from the dipstick tube and it's still running so well . 

[pacer 3,176]

I'm not familiar with the small K series, so I dont know its amount   -- but its prolly only around a quart, so drain it and either rule out gas in oil or not. That will at least solve, or find, one of the possible probs.

[RED-Z06 2,479]

Single cyl engines will always blow air out the case, Remember that every time the piston travels up it displaces 18 cubic inches of air and when it goes down it does the same, plus any blowby which is normal.  The crankcase vent lets excess air out on the down stroke and creates a light vacuum on the up stroke..but if you have an opening such as a loose dipstick, you see the rush of air.

[squonk 42,598]

You need the correct length dipstick that seals in the tube before tearing things apart again. The stick hitting the pan and vibration is enough to force it out.

[pacer 3,176]

55 minutes ago, RetroMower said:

the dipstick flailing wildly. There was an impressive amount of air cycling out of the dipstick along with a lot of oil

 

@RED-Z06 I agree with your description of a NORMAL small engine, but the above description - to my thinking - Is way beyond that.

 

59 minutes ago, RetroMower said:

impressive amount of air

 

This makes me think its unlikely gas in oil .... but, what is the prob ????

[RetroMower 349]

Can short videos be uploaded here? I feel seeing it in action is the only way to convey just how much air is pumping out of the crankcase 

[RED-Z06 2,479]

Here is my M12S with about 25hrs on a rebuild, it blows alot of air out..but once the stick is lowred it actually creates a vacuum and sucks the stick down.  Opened up it will blow oul vapor all over the place 

 

 

[squonk 42,598]

1 hour ago, RetroMower said:

I put a compression tester on it and got around 60 psi

That engine has automatic compression release. 60 PSI at cranking speed is about all you will get.

 

 

[rmaynard 15,933]

If this has already been asked, sorry, but did you reassemble the crankcase vent correctly?

[RetroMower 349]

38 minutes ago, rmaynard said:

If this has already been asked, sorry, but did you reassemble the crankcase vent correctly?

Going back to when I decided to buy this round fender I knew I'd be dumping a lot of $$ into it so I was thankful the motor ran so well and therefore not needing a rebuild so I haven't touched the breather. I thought I'd have noticed this problem but I guess it's worth checking if a prior owner had it apart and reassembled it incorrectly 

[wallfish 17,520]

23 minutes ago, RetroMower said:

Can short videos be uploaded here? I feel seeing it in action is the only way to convey just how much air is pumping out of the crankcase 

Use Youtube it's the best way. Free to join easy to upload, easy to link the video on here

Check the breather valve to make sure it's not clogged or installed incorrectly. The majority of K181s would have a dipstick on a threaded iron hole pipe plug with NPT threads. Should be easy to find one and remove the extension. If you think there's fuel in the oil get it out and find the problem. Fuel will spill out the front of that carb unless it's parked facing up on an angle

 but it can enter through the fuel pump. 

One thing about the K181 is they all want to run. What a great engine they are.

[oldlineman 1,495]

That's what I was thinking maybe breather problem ( clogged , assembled wrong ). Bob 

[RetroMower 349]

Took the breather/vent apart and it's not clogged or installed wrong. The fiber element in there disintegrated when I looked at it tho. The replacement ones look like a green scotch brite. What's an acceptable material to make my own with?

[RED-Z06 2,479]

26 minutes ago, RetroMower said:

Took the breather/vent apart and it's not clogged or installed wrong. The fiber element in there disintegrated when I looked at it tho. The replacement ones look like a green scotch brite. What's an acceptable material to make my own with?

Ive used a mesh steel wool in applications where there is no replacement  available.. all it does is give oil something to stick to and later drain off of and back into the case.  

[Howie 899]

If one leaves the dipstick loose or takes out on one of these splash lubricated engines it

will blow oil all over the place. Especially if the tube is short or screws directly into the

block. Have had it happen to me, not one of my smarter moves, learned not to do it anymore.

Crankcase pressure will do it but so will the dipper on crank throwing the oil around. 

[oliver2-44 10,375]

FYI
if you pull the breather, I have a Kohler Service Bulletin that says on the K181 and smaller engines to use 2 of their precut breather mesh pads to reduce oil mist leakage from the breather vent   
I’ve used the blue kitchen scotch brite for breather mesh. They say the red and green ones have some abrasive grit on them 

Edited February 8, 2022 by oliver2-44

[RetroMower 349]

On 2/6/2022 at 10:57 AM, RED-Z06 said:

Here is my M12S with about 25hrs on a rebuild, it blows alot of air out..but once the stick is lowred it actually creates a vacuum and sucks the stick down.  Opened up it will blow oul vapor all over the place 

 

 

After a couple brutal days at work I finally got to fully investigate my issue and reinstall the breather. Turns out RED-Z06 was dead on with his advice. If I hold the dipstick down or angle it just so it stays in place. When removed and I put my hand over the dipstick tube I can feel a slight pulsing but once the seal is broken it chuffs pretty good. My dipstick is either not original to this motor or the rubber grommet is so dry and shrunken it barely seals anymore. I never encountered this issue on my horses primarily because they are all threaded plugs. If anyone has a k181 plug/dipstick for sale I'd be grateful.

Edited February 10, 2022 by RetroMower

[RED-Z06 2,479]

1 hour ago, RetroMower said:

After a couple brutal days at work I finally got to fully investigate my issue and reinstall the breather. Turns out RED-Z06 was dead on with his advice. If I hold the dipstick down or angle it just so it stays in place. When removed and I put my hand over the dipstick tube I can feel a slight pulsing but once the seal is broken it chuffs pretty good. My dipstick is either not original to this motor or the rubber grommet is so dry and shrunken it barely seals anymore. I never encountered this issue on my horses primarily because they are all threaded plugs. If anyone has a k181 plug/dipstick for sale I'd be grateful.

What's your dipstick look like?

[Jeff-C175 7,203]

1 hour ago, RED-Z06 said:

What's your dipstick look like?

 

Gettin' a little personal there, ain'tcha ?  

[RED-Z06 2,479]

4 minutes ago, Jeff-C175 said:

 

Gettin' a little personal there, ain'tcha ?  

Isnt that what happens at night up in Pa at the show?  Everone pulls out their dipsticks to compare?

Edited February 10, 2022 by RED-Z06

[Jeff-C175 7,203]

3 minutes ago, RED-Z06 said:

up in Pa

 

Dunno!  What happens in PA stays in PA! 

 

That one you posted looks like a ladies watch band!

 

Edited February 10, 2022 by Jeff-C175

[RetroMower 349]

You what to see my what?!  lol

 

As I said I dont think this is original to this motor. You can see the end is mushroomed from tapping the oil pan. 

[RED-Z06 2,479]

A231495S is a K181S part number..