Farmall m burning oil

Le9102011

Member
Hello all. I have a 1947 farmall m that I just picked up was having carb issues rebuilt the carb and seems to be running better but it was still hot. Took it to a tractor show and found that the timing was a little retarded fixed that issue now it seems to be burning oil if I richen up the mixture took the plugs out and they where wet. Found it had a crank case pressure relief problem cleaned that out but then it started burning oil again. Leaned out the mix and the oil smoke when away. Just wondering if these engines are supposed to run hotter to alleviate this or is the engine about to grenade. Engine dosent have any blow by and has loads of power. Pulled a 19 in plow in 4th gear and almost idle. Love the farmall m it?ll give my John Deere g a run for its money.
 
Just curious, but what did you do to cure the crankcase pressure issue? Sounds more like a rich mixture than a burning oil issue. Having no blowby is a good sign
 
First I pulled the oil fill cap off and it seemed to clear up a bit and noticed I didn?t have really anything coming out of the vent pipe so I took it off and pulled the mesh that was in it out cleaned it and pushed it back in. I was thinking the same thing with it being rich but the smoke was more of a blueish gray and smelled like oil vs dark gray or black.
 
It?s a blueish grey smoke. I have the idle adjustment needle cracked maybe a quarter turn it that. This is my first farmall so on my Deere?s the exhaust gas isn?t all that hot but on this farmall when I lean it out to where it stops smoking the exhaust is so hot coming out of the pipe.
 
What is happening to the oil level in the pan?

If you are actually burning oil, the oil level will be going down.
The exhaust gas will have a distinctive smell.
These old tractors generally used some oil during real-life operation.

What is happening with the water temperature gauge?
If your timing is late and/or the engine is running too lean, the water temperature will go up.
 
I want you to time it by ear, then test.

Run it at wide open throttle (WOT), rotate the distributor slowly, back and forth until you achieve the maximum RPM, then lock it there. If it pings under load, or has a little lope at idle, then back it off a little.
 
I'll toss in 2 cents worth to think about. You stated previous carb problems. If so is it possible that a rich mix existed possibly bypassing rings with unburned fuel diluting oil and allowing it to pass rings and be burned when operating properly? Also this can occur from excessive use of the chock and short runs never allowing engine to reach operating temperature for enough time to evaporate contaminates from oil. Just something to think about and use or trash can as you see fit as I can't see or operate your unit.
 
Well I hear ya there it dose smell like oil but it isn?t using hardly any if any at all. When I was messing around with it I do know that when I was running it really lean or the timing was retarded the manifold would get so hot you could hardly be around it with out breaking a sweat even and that was just after a few mins of it running and it was popping like crazy. I got the timing I think just perfect and after I leaned it out to where it stopped smoking the manifold wasn?t all that hot but the exhaust coming out of the pipe was really hot.
 
Check the air cleaner inlet down pipe. I have found them choked down to the size of a nickel from oily crud.

It would typically be down on power if choked off too badly but it's worth looking into.
 
Well on every Deere I?ve worked on or rebuilt exhaust is cooler than the manifold. It may just be me being a worry wart but I just don?t want to grenade a perfectly good engine by running it too lean. But I do know that after running it for like an hour doing light work or driving it in a parade the temp gauge doesn?t move nor is the engine or the head too hot too touch. This is my first farmall and I just want to make sure I get it done right and I get a lot of enjoyment out of it vs dumping money into it and saying leave the red in the shed. I caught enough crap today tinkering with it wearing a Deere hat.
 
The old girl may not have done any honest work in a few years.
The temperature gauge will not come up puttering around.
They were meant to work, just like your John Deere G.
A few hours pulling a plow or disk might help a lot.
A set of hotter plugs might help a lot, too.
 
I would have to agree with ya there. I?m gonna borrow a bigger plow tommorow and sink it into the ground a drag the old girl for a little while. The 1 bottom plow with a huge mold board ain?t nothing for it or the g. Gotta love passing by everyone in the field some guys should be usin my plow and I use there?s.
 
Black exhaust smoke is from rich fuel. Blue smoke from oil. White smoke from water/anti freeze. What color is exhaust smoke?

If burning oil, you should be having to add a court of oil one or more times in between oil changes. Your carberator adjustments should have nothing to do with wether or not it burns oil.
 
So the problem isn't that its burning oil but that its blowing smoke.

Sounds like its running rich and the timing is still screwed up.
 
Here is a little science on timing.

Early timing will ignite the fuel too early and kick back on the piston while it is still coming up, symptoms are knock or ping. Correct timing will ignite the fuel at the appropriate time so that all is burned while the time the piston gets down, so there is no unburned fuel left. Late timing ignites too late to fully burn the fuel by the time the piston gets to the bottom and will push unburned fuel out the exhaust, this fuel burns in the exhaust, symptoms are hot/red exhaust, low power and blah sound.

The correct point for ignition is around 15 ATDC, so can vary between 10 and 20, so that the flame front pushes where the crank angle provides the most torque and there is enough time for fuel to fully combust inside the cylinder. The flame front will move faster under load, so that is why the timing cannot be as advanced if the engine is heavily loaded. The timing will also need to be advanced enough to compensate for the delays to assure the flame front reaches the piston at the correct time.
 
When I said correct point for ignition being 15 degrees ATDC, I meant for the flame front to reach the piston. It does take time for the flame to go from the spark plug to the top of the piston.
 
Late timing can really heat a turbo up in a hurry, we back the timing off to 27 ATDC on some of the big natural gas engines after starting to get the turbo's warmed up. It is a delicate situation, as the cold turbo will not provide boost, and the late timing takes all the torque out of the engine. Once the turbo is warmed up, we advance the timing back up to where it will work well.

These are 300 RPM engines 6000-10000 HP.
 
engine timing on and M can be darn near anything from what they were early to the latest advance timing change of somewhere between 24-27 degrees BTDC at full throttle so god only knows what has been done to yours over the years and what pistons and head it may have Carb setting on the main screw should be no less the 3 and 1/2 turns off the seat on up to five turns off and when your good at tuning one you can darn near count the fan bales as they turn at idle but 450-475 is good .
 
I would get the ign. timing correct then go from there. If it's a distributor make sure the point gap is set at .013 of an inch this will affect the timing and may be if too far off for turning the distributor to correct. and make sure the distributor shaft is not loose in the housing bushing from wear if it is the point gap will change when it is running. Then set the timing this is easy to do with the engine off turn the engine by hand until the pointer lines up with the first of the 2 marks this is the btdc mark this is just a few degrees of advance, the static timing for idle the distributor advance takes over as engine rpm and load increase you can check if advance is working later. With the first mark lined up take the coil wire out of the distributor cap and secure it like 1/4 inch from bare metal, loosen the distributor, with the ign. switch on turn distributor back and forth to find right where the coil wire sparks then tighten it. this is IHC specs. The advance can be checked with a timing light just mark the pully marks with whiteout or paint and watch the marks with the light as raising the rpm they should move and go back when slowed down.
 
something to check, the older these things are getting we are finding more manifolds leaking exhaust into the intake from a hole rusting or burning between each part. This causes all kinds of crazy problems might check that too.
 
Thanks for all the help I found the culprit the valves were too tight and sticking. Now I think I have it timed correctly and firing on all cylinders buuuutttt I barely have to turn the idle adjustment screw out to get it to run correctly maybe a quarter turn any more than that the rpms drop and it starts rolling coal like a freight train And starts popping. My only concern now is how hot the manifold is getting and if I?m running it too lean. It does have the distillate manifold so I?m goin to assume that is a normal operating characteristic of the manifold. I can get it too cool down by turning the distributor cc but the rpms go up and I can?t get them to come down. The engine isn?t getting hot and once i stop the engine and pull the plugs I can stick my finger in the hole and it?s not too terribly hot.
 

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