C160-8 oil loss without smoking

[Fj40z 219]

Hey all, my C160-8 is losing oil without smoking any at all. I mainly use it for mowing so it’s pretty much under some load at all times. Using Kohler 30w oil and I’ve smelt the dipstick and get no gas smell at all. I do see a lot of dusty oily residue at the front of the motor around the air filter and carb area and the front of the motor that wasn’t there before. It may have already been oily there and I just noticed it today since it was so dusty from being super dry here. Looks like a lot of build up around a small slit on the front of the motor. Seems to be running fine other than the oil consumption. Please excuse my ignorance LOL. Any help or insight it very appreciated as usual. 

[ineedanother 2,825]

Define "loosing oil" if you would. A small amount on the dipstick between oil changes shouldn't be alarming IMO...and clean that thing 

 

You might want to pull the valve cover and make sure that it's clean so oil can return to the case rather than being blown out the vent. Replacing those gaskets might be in order. Looks pretty good to me for a working  unless I'm missing something. A good rinse might show something more but I'm not seeing it.

[mrc 1,110]

 

 

one of mine is a lot dirtier!

[ri702bill 12,867]

More than 1000 hours on it? It might be time for a leak-down test. Older engines can consume oil due to worn rings or valve guides, yet perform well. If it's not leaking it, it's using it...

 

Big question - what weight & type of oil are you using? IMHO - using modern automotive multi-weight oil is a no-no for several reasons. Modern car oil has almost no zinc content - essential for flat tappet cam and valve guide life on these older style engines. Multiweight oils are thin - Kohler recommends straight 30 weight oil for summer usage.

[squonk 47,923]

My C-160 was using oil with no smoke.  About a pint every month. 1000 hrs. Ran fine. Had a slight rattle. One spring the rattle got a little louder so I decided to put another engine on and tear the original down. Out side of loose balance gears I found this:

 

Edited yesterday at 10:05 AM by squonk

[ri702bill 12,867]

So much for the oil control ring! 

[WHX?? 57,862]

5 hours ago, ri702bill said:

what weight & type of oil are you using?

 

9 hours ago, Fj40z said:

Using Kohler 30w oil

He stated Bill.

Might be worn rings causing some blow by to push oil out the breather. Fairly typical with our  working singles. 

[squonk 47,923]

Another place to look is erosion of the top of the piston in the area closest to the exhaust valve. Seen this alot! 

 

[pfrederi 21,087]

What does your spark plug look like???  Picture please

[Fj40z 219]

Yeah using Kohler 30w oil. I’ll have to get a pic of the spark plug when I get home from work. I’ll also try and get it cleaned off good when I get home and see if I can isolate where it’s coming from mostly. I hope it’s nothing major, I’m very green on the ins and outs of small engines. I know it’s old and I can live with adding a little oil and small oil leaks, just hoping to avoid a catastrophic failure.

[squonk 47,923]

1000 hours. The balance gear bearings are probably getting loose.

[Fj40z 219]

7 hours ago, pfrederi said:

What does your spark plug look like???  Picture please

 

[Fj40z 219]

This one didn’t come with a hour meter.  Has a factory block off plate where the hour meter would have went. I’d wager it has weeeeellllll over 1000 hours on it. I bought it from the original owner and they used it only for mowing for decades so there’s really no telling how many hours it has on it.

[rjg854 13,325]

32 minutes ago, Fj40z said:

 

That doesn't appear to signs of burning oil

[Fj40z 219]

@rjg854 I agree, looks pretty good to me. 

[Fj40z 219]

Cleaned it up some and let it run and get hot. Did not see any leaking but possibly only leaking under load? 

[sqrlgtr 3,748]

My K161 7hp on my 701 leaks oil at the oil pan and block and if you park it in the gravel or dirt shed you dont even notice the oil slick thats under it, but you sure can in the concrete shop . May not be your problem but the spark plug you show doesn't appear to be that bad to me, if they are burning oil badly, they are usually wet with oil. Just throwing this out there because I thought mine was burning oil bad but turns out it was just marking its spot.

[WHX?? 57,862]

I would say then is pop the head and check for oil wash. Never hurts anyway to check the bore, valves & decarbon. 

[Fj40z 219]

8 minutes ago, WHX?? said:

I would say then is pop the head and check for oil wash. Never hurts anyway to check the bore, valves & decarbon. 

I’m not familiar with the term oil wash?

[adsm08 5,029]

4 minutes ago, Fj40z said:

I’m not familiar with the term oil wash?

 

Me neither. Google didn't know it either.

 

I've heard of gas wash, but ever oil.

[WHX?? 57,862]

9 hours ago, Fj40z said:

I’m not familiar with the term oil wash?

Where the top of the piston and combustion chamber has no carbon because of leaky rings. Dan skooled me this. 

@Achto got a pic??? I'm sure the Squonky @squonk has seen it. 

Edited 1 hour ago by WHX??

[Achto 32,395]

 

 

 

This picture shows piston wash. The clean area is from oil getting past the rings and washing the carbon off the top of the piston. 

 

[squonk 47,923]

10 hours ago, WHX?? said:

I would say then is pop the head and check for oil wash. Never hurts anyway to check the bore, valves & decarbon. 

And whilst you're in there look at the piston edge closest to the exhaust valve. I bet it's eaten away.

 

Edited 59 minutes ago by squonk

[pfrederi 21,087]

I would think if all that oil was getting up past the rings the plug would have been fouled....

[WHX?? 57,862]

Just now, pfrederi said:

I would think if all that oil was getting up past the rings the plug would have been fouled....

I would also think it would smoke??