Having Problems, Did a Compression test, need opinion

[Woodscustom]

Hey Guys,

I m working on my Farmall A, which belonged to my Father in Law. He restored it 10 years ago and it has been setting in the barn since. He passed and now I m trying to get it back in service.

I had to do a fuel tank cleaning, carb rebuild, oil change and new Battery. It runs great and sounds pretty good. BUT, once it warms up it starts smoking on and off. The white/blue smoke clears up when setting at idle, and as soon as you take off again, it starts right up within a minute or two. NO SMOKE is coming from the breather, all of it is out of the exhaust stack / oil specks on the hood.

I put in a quart of Seafoam in the crankcase and a pint in the fuel tank. Put an hour or so on it, still smokes.

Figured I better go deeper so I pulled the plugs. 1 & 2 look good. 3 & 4 have a LITTLE oil on them. I did a warm engine compression test and here are the results.

#1 DRY 90 psi No leak down after 5 min. WET 110 psi
#2 DRY 90 psi No leak down after 5 min. WET 110 psi
#3 DRY 85 psi Leaked down to 80 - Wet 100 psi
#4 DRY 90 PSI Leaked down to 85 Wet 115 psi

What would you do next? I m thinking about pulling the head and taking a look. Or is it just time to rebuild the ol A and be done?

Thanks,
Woodscustom

 

[tractorsam]

Id probably try putting a load on it and getting it good
and warm before I went any deeper.

 

[old]

I'd put about a 1/4 cup of ATF in each cylinder and let it sit a few days. Good chance it has ring that are sticking

 

[Woodscustom]

I am in total agreement. The oil pressure is spot on and everything points to a stuck ring or some sort of valve carbon issue. I will let it set for a few days with ATF/PB Blaster mix, then take it out and put a load on it and see if it improves.

Any other opinions or someone with similar experiences with this issue?

Woodscustom

 

[BarnyardEngineering]

I'm a little confused. What exactly points to a stuck ring?

The compression numbers show a well-worn, but not worn out, engine. They're all within 10% of each other which is exactly what you want to see, but rarely do.

To my way of thinking a "stuck ring" would show as a significantly lower compression number on one or more cylinders.

The only way this would make any sense is if ALL the rings were stuck.

First thing I would do is give it what Vice Grip Garage calls the "Eye-Talian Tuneup." Get yourself a can of Berrymans B12 or Seafoam, put it in a spray bottle, remove the air cleaner, warm up the engine, then stuff the entire bottle "straight down its yap" as he says. Spray it into the intake as fast as you can without killing the engine. You might stall it a time or two before you figure out just exactly what you can get away with.

When you run out of stuff, shut 'er down immediately. Let it soak over night. Next morning it should belch out a cloud of smoke like you wouldn't believe, but then the smoking should be better.

I was doing this before Youtube was a thing. Learned it from this website. Maybe it loosens rings. Maybe it takes out the carbon deposits. All I know is the engines almost always smoke less after this treatment.

 

[Dave41A]

Oil spots on the hood make me think the valve guides are leaking. It may be there all the time and just become apparent when you throttle up and the increased exhaust flow is enough to blow the oil out the exhaust.

Are the plugs fowling or wet with oil? I would check them. I am not there looking at your tractor, and don't know what your father-in-law had done, but what you describe could be all due to top end problems. You wouldn't pick this up on a compression check as that is done when the valves are closed.

 

[Woodscustom]

Cylinder 3 & 4 had a little oil on them. Doing a tear down doesn't feel right to me right now. I'm going to do the soak er down thing and the Eye-Tallian overhaul and put some hours on it.

Any other options or ideas?

Thanks for your help guys.

WC

 

[old]

Fill the cylinders with ATF and put the plug back in. Then pour as much ATF down the exhaust as you can till it leaks some place. That way if there is carbon build up on the valves the ATF can clean it off

 

[caterpillar guy]

Filler up with gas check the oil take a quart with you and go work the tail off of it. She will clean up with use. All the snake oil in the world will not make it a new engine. I don't buy the stuck rings. Loose guides and valve yes. for that again work the a$$ off it for a few days. Plow all you can plow or some other heavy work working its tail off. Not for a few hours an all day hard work for as many days as you can get long hard days.

 

[RedMVa]

Cat guy and barnyard have it, nothings stuck. Valve
guides wore, compression on low side.

If rings were stuck youd be getting blowby out of
crankcase breather. For Petes sake dont make a mess
out of it slobbering it with oil

 

[grandpa Love]

I use marvel mystery oil, transmission
fluid or Lucas fuel treatment, pour it
in the carb until I almost kill it,,,,
repeat several times! Then pour enough
in to kill it, leave it over night,
almost always makes a difference!
Terrible smoke show ( don't do this in
the shop ..... Don't ask! Lol

 

[Woodscustom]

(quoted from post at 17:24:18 07/29/22)
Terrible smoke show ( don't do this in
the shop ..... Don't ask! Lol

Oh, I'm doing it!

Right after I tell the wife to come out and tell me if she sees any smoke when I fire it up.

WC

 

[Dave41A]

OK, re-reading I see the note on the fouled plugs in the original post. I still think it is guides or guide seals. You can run these tractors with the valve cover off--for a little while, anyway. You might want to try that to see if you can observe anything.

The reason I think this is the droplets of oil you see on the hood. If it was rings, this oil would be burned. I think the oil is getting into the exhaust after the cylinder. You probably have some leakage on the intake valve too. That would explain the fouled plugs. Worn rings is also associated with a consistent blue smoke, while here-and-there blue smoke seems more like valve guides to me. Worn rings would also give you blow-by to the crankcase, which you do not seem to have. Is there are 'exhaust' from the breather when you throttle up? (Carefully feeing with your hand)

 

[Woodscustom]

(quoted from post at 19:20:09 07/29/22) Is there are 'exhaust' from the breather when you throttle up? (Carefully feeing with your hand)

I will check that out in the morning and let you know.

WC

 

[Woodscustom]

(quoted from post at 19:24:49 07/29/22)

(quoted from post at 19:20:09 07/29/22) Is there are 'exhaust' from the breather when you throttle up? (Carefully feeing with your hand)

I will check that out in the morning and let you know.

WC

I feel pressure, nothing out of the ordinary.

WC

 

[Woodscustom]

(quoted from post at 19:20:09 07/29/22) OK, re-reading I see the note on the fouled plugs in the original post. I still think it is guides or guide seals. You can run these tractors with the valve cover off--for a little while, anyway. You might want to try that to see if you can observe anything.

I did observe a bent pushrod on #4 exhaust, and a couple other iffy ones. I'm going to pull the rocker arm assembly , pull the pushrods,, roll test them, and count em up.

Also I found a new hole in the manifold, exhaust side. Gonna have to get one of those too.

Question..#1... Are all of the carburetor flanges the same on all manifolds for the A Tractor? I have a Zenith carb on mine. It looks like Yes.Trac has them new for $93.00.

Question..#2... What is the torque spec for the rocker arm assembly?

Thanks,

WC

 

[old]

Bent push rods say sticking valve and ATF treatment can help with that and if an exhaust valve pouring it down the exhaust help a whole lot

 

[Woodscustom]

Here is a YouTube video of the pushrods with the engine running.

https://youtu.be/XtHGsI2xr-o

WC

 

[Welding man]

Nothing works as quick as a Dyno. It will make the problems show up quick.

 

[Dave41A]

Here's another check you can do. Run the tractor, then let it sit for a few days. If it is guides, oil will leak into the cylinders from above. Then start the tractor. If it smokes blue smoke on startup, then clears while idling, I think you can be sure it is guides, as you're burning off the oil that dripped into the cylinder while sitting.

With older equipment, solving one problem does not mean ruling out others. You could still have a stuck ring. Or a stuck ring on one cylinder, and a leaky guide on another. But check one thing at a time to step-by-step eliminate possibilities.

 

[Dave41A]

(quoted from post at 21:48:14 07/30/22)

I did observe a bent pushrod on #4 exhaust, and a couple other iffy ones. I'm going to pull the rocker arm assembly , pull the pushrods,, roll test them, and count em up.

Also I found a new hole in the manifold, exhaust side. Gonna have to get one of those too.

Question..#1... Are all of the carburetor flanges the same on all manifolds for the A Tractor? I have a Zenith carb on mine. It looks like Yes.Trac has them new for $93.00.

Question..#2... What is the torque spec for the rocker arm assembly?

Thanks,

WC

Woods: Nice video. Yes, that #4 pushrod is bent, as old said that is likely due to a stuck #4 exhaust valve at some time. It would not surprise me if that is where the bad guide is.

I would tackle the manifold first. Then maybe you can look in and check for signs of oil leakage on the valves. If you see oil in there, then you'll know the next step is to pull the head & get that ship-shape. You'll have a good head and know how many hours are on it when the time comes for a bottom-end rebuild.

Yes, all the 'A' manifolds should have the same two-bolt (front/back) carburetor flange. Mine has a Zenith on it, too.

No torque spec for the rocker arm studs/bolts. They are probably 5/16 or 3/8. Maybe 15 ft-lbs? They are not under a lot of load.

Looks like you are making good progress getting to the bottom of things. Dave

 

[Woodscustom]

(quoted from post at 14:00:44 07/30/22) Bent push rods say sticking valve and ATF treatment can help with that and if an exhaust valve pouring it down the exhaust help a whole lot

I took the manifold off and took some pics. #3 Exhaust is the one that is wet. The other exhaust valves look the same.

I filled them up with ATF and Marvels. #3 leaks down in about a half hour.

WC

 

[Woodscustom]

UPDATE:

After putting 10 hours on the A, It never did improve, maybe even gotten worse.

I pulled the head and sent it off to get freshened up, decided to pull the oil pan and look around. Since I was that far, I decided to go ahead and put in new rings and rod bearings from YT.

This is what I found.. Every piston ring was put on upside down and not clocked. The rod bearings said FM 62 (1962) so I guess this A had been this way for quite some time.

WC