Hi, Looking for any thoughts on the engine issues with my 861 gas tractor. It smokes quite a bit with blow-by coming out the valve cover vent and the oil filler tube. I ran the engine to operating temp for a while with both valve cover vent filter and the oil filler cap removed. Smoke coming out of both. After running a while, I noticed the oil in the inner sides of the oil filler tube collected some oil that was tan colored.... as if it were water contaminated. I changed the oil and the old oil looked okay, it was not discolored and did not appear to contain water. The compression (cold engine; dry) ranged from 110 to 125. I tried looking for oil in the radiator, but did not notice any. I would have to do that again to be sure.
Does this sound like a blown head gasket or worse? Local mechanic thinks its a good engine and just needs a valve job, but they did not spend much time looking at it. I can get a good used engine for 20% less than the valve job cost, and worried my engine will have more issues that will escalate the cost.
Thanks.
 
Does this sound like a blown head gasket or worse?

Doubtful the head gasket is blown - Your compression readings are good.

What color is the smoke?
Does it smell like antifreeze or oil?
Does the smoke linger in the air or evaporate?

The tan colored oil in your filler tube is likely due to condensation. Cold/damp weather creates a lot of water vapor.

If it truly is oil vapor coming out of valve cover and breather it is likely due to stuck, worn or broken rings.

Lets approach this as if you have one or more stuck oil control rings. I always do the cheap and easy things first.

Pull the plugs and put a couple of tablespoons of ATF in each cylinder. Leave the plugs loose and let it soak for several days. After it has soaked, remove the plugs and spin the engine to blow out any remaining ATF, then tighten the plugs.

Next, drain a quart of oil from the crankcase and refill with a quart of ATF.

Add a quart of oil to the gas tank and then go work the tractor for an hour or so to evaluate your efforts.

Note: Depending on how much gas you have in the tank, the ATF may cause some exhaust smoke but that's okay.

This may not solve your smoking problem but at least you will only be out a little time and a couple quarts of ATF.
 

Farmer Blair, listen to your local mechanic and Dollar Bill. Your tractor is suffering simply from that extremely common old tractor malady: "lack-of-work-itis" Not enough heat generated to evaporate off the moisture of combustion. Avoid starting it unless you really have some work for it.
 
I would make sure it has a good 180-190 thermostat and work it good, will boil out condensation.
 
Thanks Dollar Bill. Here's answers to your questions:

What color is the smoke? Mix of blue and white
Does it smell like antifreeze or oil? Not antifreeze; oil
Does the smoke linger in the air or evaporate? The smoke lingers, and plumes out to 50 feet or more. Too much smoke to sit and use tractor for long.

I'll try your procedure to mix ATF to the oil and cylinders. Not sure if you meant that I should add oil or ATF to the gas tank.
 
Thanks Dollar Bill. Here's answers to your questions:

Thank you for the straight answers which confirm that it is oil vapor as you originally indicated.

Sorry for the mistake, I meant "add a quart of ATF to the gas tank" instead of oil. ATF has cleaning/penetrating properties. Adding it to the cylinders and crankcase will reach both sides of the rings. ATF in the gas helps mostly with lubricating the valves. ATF will also mix with water to dehumidify your gas tank.

Trying to determine if rings are stuck or broke: What is the history of the smoking problem - Did it go from oil tight to smoking overnight or was it a progression over time?
 
I agree to clean up the engine first before you do anything rash. ATF was recommended, I use Sea Foam, (Naptha, Alcohol, light mineral
oil). I don't know what's in ATF but I used to keep it in my OTR diesel tanks (1 qt./100 gallons) and never had fuel issues.

Trick I heard of and used was to remove the radiator cap with the engine running and up to temp where water is circulating at idle rpms. If
you see any bubbles, you have a head gasket (or cracked head on my 4 cyl 4000...which was said to be common) leaking compression
gasses into the cooling water. On the intake stroke the leak would allow coolant to enter the combustion chamber.
 
Alexander's Ford parts and refurbishment business in Mt. Pleasant (East) Texas had a machine shop that specialized in repairing cracked heads. They would drill holes along the crack and drive lead plugs into the holes. I bought one for my 4000 and used if for many years with no problems.
 

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