Engine Re-assembly Questions

I"m getting ready to reinstall the head and manifold on my 1938 JD B. The head has been reworked, the manifold planed flat, and all parts/gaskets acquired. I"ve read the I/T manual, but of course, it doesn"t cover every detail. Since this is my first time to do it, I want to get it right because head gaskets are damned expensive.

1. On the manifold studs, how far do you screw them in to the head......until they bottom out? Obviously, the short threaded end goes in the head, but if you screw them in all the way, will they hit the pushrod tubes?
2. What do you put on the ends of the manifold studs to prevent water seepage around the threads? I"ve heard Permatex mentioned, but what kind?
3. Should I put any sealant or anything on the manifold gasket to prevent leakage?
4. Should a flat washer and lock washer go under the nut on top of the stud? How tight should the nut be? I want to get it tight enough to prevent leaks, but don"t want to break off manifold ears.
5. Should any sealant be put or sprayed on the head gasket?
6. I"ve heard of people torquing the head nuts to the proper specs and in the correct sequence, and then loosening all the nuts and doing it again. Is this a good technique? (Seems like you"d defeat the sealing capability of the lead washers.)
7. On the two long bolts which hold the rocker arm assembly, do I need to put any kind of sealant on the threaded end which screws in to the head? How about the other end that the acorn nuts screw on to........will oil leak out of these holes without some sort of sealant or washer?

Yes, it"s a lot of questions. I"m determined to get this right and appreciate your input.

1. If you have the correct JD studs, you don"t have to worry about hitting the pushrod tubes.
2. I"ve always used teflon tape with no problems.
3. I always put a real thin skim of silicone around the intake part of the gasket, both sides.
4. I put flat and lock washers on the manifold studs. No mention of torque in my IT manual.
5. I always spray CopperCoat on the steel side of my gaskets. Never had a problem.
6. Torque the nuts, start and run. Check torque after running for 15 mins or so.
7. No need for sealant on the end of the studs. The nuts should have copper washers under them.

Just remember the copper washers under the nuts are NOT there to seal anything. The purpose of the copper washer is to reduce drag between the nut and head surface to achieve the proper torque.

Do not re-torque until the tractor has been run up to FULL "Heat-Soaked" temperature..roughly a good FULL hour under Load..THEN, re-torque the Head..WHILE HOT..

Ron..

(quoted from post at 17:52:48 01/29/13) Just remember the copper washers under the nuts are NOT there to seal anything. The purpose of the copper washer is to reduce drag between the nut and head surface to achieve the proper torque.

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Another thing you can do to reduce drag is put a little bit of never-sieze on the threads to help the nut to turn easier.

It is not the threads but the gauling of the cast iron head that the lead washers were used for.

All,

Thanks for the comments and advice - I'll take it all and give it my best shot.

The copper washers I was talking about go under the acorn nut for the valve cover (A437R). These are "supposed" to seal the cover. He should also have some kind of washer (lead, copper) on the head studs as well.

I got the lead washers for the head studs, but still need to get washers for the acorn nuts. Thanks for the tip!