Farmall A: can I pull head w/out removing rockers???

I picked up a nice 1946 Farmall A. (actually, it's an AI, industrial). Previous owner gave up on it as it kept getting stuck, even after local truck shop, "fixed," it. I think it's got a bad wet sleeve o-ring and it keeps taking on coolant which sticks the engine. More on that if needed.

Anyway, I brought her home and put it inside, which made the tractor happy since it's been out for the past few years.

I pulled the valve cover and rockers, etc., look crystal clean. I'm pretty sure the truck shop overhauled the cylinder head. I want to pull the head to inspect the cylinders. Then I'll have to wait until Spring, at least, to be able to afford to have the engine repaired correctly. Of course a few of the head bolt nuts are under the rockers to some extent, and I suspect any shop would just pull the rocker arm first. However, in the interest of keeping things roughly together until Spring, can I pull the head without removing the rocker arm?

Thanks, Dennis --- pretty happy with his new find.

It has been a while but I think you pretty much have to pull the rocker assembly to pull the head off but after you have the head off there is no reason you could not bolt it back on hand tight would be all that was needed to keep things together. Also if your just going to let it sit that way I would put a bunch of ATF in the cylinders and lay the head back on just to keep it clean, But if it was me I would leave it together till you have the $$ then open it up. I would still fill the cylinders with ATF and make sure the radiator and block are drained

Take some pictures and then you can look at them. I wonder if the head was magna-fluxed when in the shop. Hal

Thank you. My idea for pulling the head was to see what things looked like and make sure there was plenty of lubrication/oil/ATF-diesel mix, etc., everywhere needed.

I doubt the shop magnafluxed anything. Here's the story: prev.owner took it to shop because engine was stuck. Shop pulled the head and when it went back together it ran, "fine." They put it back outside where it sat for 3 months before owner picked it up. It was stuck again when he picked it up. He gave up. I got it two years later.

I pulled pan drain and got water and anti-freeze. I pulled spark plugs to put ATF/diesel mix in cylinders. (Which I already did as soon as I got it home !!) When I pulled second plug darned if I didn't get water/anti-freeze out of the plug hole. (nice) I under these are wet-sleeve engines that have a water seal at the bottom of each sleeve. I think there is either a bad sleeve seal or a crack somewhere, (I hope it's not the latter)

If I do pull the head I'll see what I can do and set the head back on so everything's covered and oily.

Dennis in E WA state

i would drop the oil pan and see what sleeve is leaking. if you are getting coolant in the cylinder, i would suspect either a cracked cylinder, bad head gasket or cracked head. if the o ring is leaking, it would generally leak into the oil pan, not fill the cylinder. when you pulled the spark plugs, you should know what cylinder had anti freeze in it. been a while since i overhauled that engine, iif i remember, the head holds the top of the sleeve in, and the head gasket helps to seal the top of the sleeve.

Right after I got the tractor and drained the crankcase, I pulled the pan. Nice and clean. Then I filled the radiator with water and layed under the exposed crankcase to watch for water/drip. Nothing. But someone said it would probably have needed pressure to cause a drip. I drained everything and gave up on that idea.

Dennis

If you are getting water in the cycl its not the o-rings. You either have a bad headgasket or a cracked head. You will have a hard time getting the nuts off the studs to remove the head without removing the rocker assy. You could also have head rusted thru letting water from the exhaust port leak into the combustion chamber. In either case you will need to remove the head. Rite now i wouldnt remove pistons ect as the problem lies in the head or a cracked block between the cycls and you wont know till removing the head.

"Farmall A: can I pull head w/out removing rockers???"


No. You can't get at all the head bolts without pulling the rocker arm assembly off first.

Get that head magna-fluxed to make sure its not cracked. Hal

Red Dave is on target. You might be able to get the head off using a box end wrench, but you will NOT be able to tourque it back down properly because of the clearance to access the nuts..........trust me, I tried, my tourque wrench with socket on it would not clear the rockers on a couple of nuts on the head. The rockers are easy to take off, so just do it. You are going to have to set the valve lash anyway, so what are you saving by not taking the rockers off.

ps. the reason I tried to use a tourque wrench with the rockers on was to re-tourque the head to 80 lbs. (i had coolant seepage around the head gasket).

Dennis, lets start at the begining. 1. Tractor has a history of engine getting stuck. 2. Cylinder head was removed, checked, reinstalled by a shop. 3. Engine stuck again. 4. You got the tractor home, dropped the pan and found water and antifreeze. 5. You filled the cooling system, but saw no coolant at the bottom of the sleeves. 6. You found coolant when you pulled one plug.

Those are the facts, correct? When you checked for coolant at the bottom of the sleeves, did you make your observation over several days? Because coolant might be leaking from the head gasket and passing down through the rings. Early A's don't have preasurized coolant, but heat expansion could cause it to leak when warmed up. Pistons could be sucking coolant in if the head gasket does not seal at the top of the sleeve, too. If the engine was not stuck, I'd say do a compression check.

If you have been soaking the cylinders, have you been rocking the rear wheels in gear to see if you can get it to turn the crank? If that does not free it up, pull the head. The rockers come off as an assembly with just three bolts, so you really can't mess that up. The rockers, springs, pedestals, all stay on the rocker shaft. Just notice that the center bolt is a special oiler bolt with holes for oil passage. But you gotta pull the rocker to get the head.

With the head off, soak it with ATF. Rock the wheels in gear, tap gently with a block of pine almost the size of the piston. Eventually it should free up.

LOOK at the top of the block where each sleeve meets the head gasket. The sleeve should protrude above the block .002-.005(as I recall) of an inch. Use a feeler gauge and your finger to check. Some call that "standout". If more than .005, it could be the problem. In that case you would need to pull the sleeve. Sometimes the sleeves don't seat at the o-ring if you don't clean that area of the block properly. Change the o-ring.

Now, if the sleeves look serviceable, remove the piston(s) involved, hone the sleeve(s) lightly. Clean the pistons and ring grooves.

Search the archives on this forum for "head gasket", you'll see where many recommend torquing the head bolts 20 lbs. MORE than the manual originally calls for. The shop that did the head may not have had that knowledge. Remember, that .002 standout is what seals the cylinder. Common problem.

If your lucky, and you seem to be because you obviously got a good deal on a great little tractor, and you've found the best forum, YT, you might get your tractor running for the cost of a head gasket($20 as I recall).
Best Regards,
Charlie

Thanks again. Sounds like what I'll do over the next few days is pull the rocker arm and set it aside, then pull the head and take it in to have checked. They could probably do a straight edge on it at the same time to see if it's warped, etc. Can't cost too much for that and it'll get be going in the right direction.

Not sure what I'll be up against if I find the head or block cracked.....

Dennis

Thanks again. Sounds like what I'll do over the next few days is pull the rocker arm and set it aside, then pull the head and take it in to have checked. They could probably do a straight edge on it at the same time to see if it's warped, etc. Can't cost too much for that and it'll get be going in the right direction.

Not sure what I'll be up against if I find the head or block cracked.....

Dennis

Thanks again. Sounds like what I'll do over the next few days is pull the rocker arm and set it aside, then pull the head and take it in to have checked. They could probably do a straight edge on it at the same time to see if it's warped, etc. Can't cost too much for that and it'll get be going in the right direction.

Not sure what I'll be up against if I find the head or block cracked.....

Dennis

Charlie in NJ:
Thanks. I think I'll do exactly what you suggest.
No heat in my old building and snow's on the ground, but not enough to keep me from doing a little each day on this.

Dennis

Dennis, do you have a compression gage and air compressor? And the engine is stuck, correct? You could unscrew the gage, screw the hose into a spark plug hole one at a time, then plumb it up to blow some compressed air down each cylinder, before you take off the head. BUT take the rockers off FIRST to close all the valves.

If you put a tablespoon of oil in the hole first it will help seal the blowby at the rings, and it will help the stuck rings, too. Put a valve in the hose, so you can control the air. Make SURE the transmission is in neutral in case the engine does break free. It probably won't.

Now, listen to where you here air leaking out. Some should come out through the rings, except a really stuck cylinder. Some might come out the valves if they don't seat well. Listen at the exhaust and then the carb. If you've only got modest leakage, look in the radiator and see it you have bubbles. Might help you narrow down the problem to one cylinder.
Best Regards,
Charlie

Hey dude if you ever feel you need to talk to some one one on one send me an e-mail and I'll give you my home number. I have done this with many people over the years and some times it seems to help them help them self's ans maybe that makes them step back and look at thing a bit different. Been doing this for over 10 years now and will keep on till I can no long help others

Ah. Some more good ideas. Yes, I do have a compression gauge. It's late now and I'm tied up in the morning. I'll pick up this thread sometime tomorrow.

Thanks,
Dennis