[rustyknuckles]

Besides the starting problem I present in another thread, I also notice that when the engine is fully hot, there is a "burnt oil smell" smoke emanating from the finned area between the exhaust pipe connection to the cylinder, and the carburetor mounting area. But NO blue oil smoke coming the muffler exhaust. I can't imagine how an oil film or oil runoff could be getting up to the area where the smoke seems to be coming from. Any ideas or opinions on this one? Thx.

 

[drew]

I read the other thread and was thinking condenser, dirty points, maybe a bad coil.

My first thought on the above is bad head gasket by the exhaust port. That might cause the symptoms of running bad and quitting. Usually you would see a fair amount of oily residue from a bad head gasket.

If you put your hand near the muffler outlet (far enough away so you don't burn yourself) do you smelled burnt oil or oil at all? Any on your hand?
Could the oil be coming from near the breather cover behind the carb? Any oil coming out the governor shaft? I'm still leaning towards head gasket but wonder about the condition of the breather.

I'm sure others will chime in with more ideas; you have a place to start. If you can clean up the oil that's there and run it you might be able to see the leak better right after you shut it off or it dies.

 

[rustyknuckles]

No oil smoke or oil smell coming out of the muffler, as far as I can tell.

Where is the breather cover? The vapors do seem to be coming out of the fins between the exhaust pipe and the carb.

I just reset the points recently; they didn't seem to be burnt.

 

[drew]

The breather cover is behind the carb, a rectangle about 3x5 with a stud and a nut.

 

[rustyknuckles]

I located the breather cover. It doesn't appear that any fumes are coming out of the little slot near the top, but rather that oil is being forced out around the edges of the breather cover. So I suppose that means the breather is clogged and needs cleaning. Or else there is too much blowby in the crankcase for the breather to handle it.

 

[drew]

The breathers are usually neglected. Cleaning helps but, replacing the little screen part is what it really needs.
Hopefully that takes care of the oil leak. The carb problem will be more of a hassle.

 

[rustyknuckles]

Well, I got the carb out of the way, removed the breather assembly, and also removed the small piece of sheet metal that surrounds the intake manifold pipe. What a mess! There was at least a pint of oily mud/dirt packed in around and behind the intake manifold, and into the fins. Also, the innermost gasket for the breather assembly was missing and the outer gasket was brittle and not sealing.

So I have ordered up two new breather gaskets, and the breather filter. That should seal things up!

I suppose it would be better to remove the engine from the tractor and steam/pressure clean the whole thing, but that is more than I want to dive into as yet. So I just dug out as much of the goo as I could get to. Stay tuned....

 

[trav1s]

Are you going to check the head gasket?

 

[rustyknuckles]

An update: I spent a few hours scraping and washing (with spray brake cleaner) the impacted black goo out from between the cylinder fins and from behind the valve adjustment chamber. I got most but not all of it, as I did it with the motor in place. Used up a full can of spray brake cleaner, and a full roll of paper towels. I had a long thin spatula that I used to reach in and pry out the goo. I also replaced the coil, and checked the valve clearance (exhaust was only 0.006 - too tight!). Also installed my fully adjustable Kohler carb.

So.... Starts and runs much better now, and does not cut out like it did before. Air flow out the front of the tractor seems much more forceful as well. Maybe engine had been running too hot because of blocked fins? I also did the water-spray trick to (hopefully) purge carbon from the combustion chamber.

I am wondering about the source of all the oil that gooed everything up. Looks like it was coming from the flywheel side of the motor, though hard to be absolutely sure. I suppose that might mean a bad seal..... Or maybe some previous owner just over-filled the crankcase?

I'm not really up for a complete engine teardown, so I will keep tabs on how oily the motor gets. This is my "parade tractor," not a work tractor, so I am hoping to just baby it along. No blue smoke when running, so cylinder and valves can't be too bad.