Packard Forum Index » Pre-War (1899-1942)

Hi All,

I'm replacing the cylinder head studs and I was thinking I should use thread locker for the part that goes into the block and someone told me to grease the end that the acorn nuts screw onto.

I'd love to hear your thoughts.

Thank you,
Crin

Gasket shellac or one of the Permatex gasket sealants (not silicone!) on the end that threads into the block. NOTHING on the threads for the nuts, it will interfere with obtaining the correct clamping force (torque), those threads need to be clean and dry.

If you are installing an aluminum head and want to do a favor to someone who will remove it in the future, you might want some grease or "Never Sieze" on the stud shank, but NONE on the threads.

Actually the manual states to liberally coat the already installed studs with grease(calcium soap base I think)for aluminum cylinder heads to prevent electrostatic corrosion problems.

Given all of the head gasket problem people are having these days, whether or not to lubricate the acorn threads is open to debate. Lubricated threads will increase the clamping force around 40%, but the risk is block distortion and stud pull out (which Pierce-Arrows love to do without Heli-Coils).

Hi

Here's the tally so far

Lube top threads 1
Don't lube too threads 1

I need more votes and a recount when it's all over... I live in Florida... Lol

FWIW, I did find this in the 1938-1939 Packard Shop Manual:
"All heads should be tightened cold and re-checked while warm. Both faces of head gasket (except Packard service gaskets which come coated) should be coated with a good grade of gasket paste and studs with cup grease before installing."

A brief perusal of post war manuals appear to be silent on the subject; this includes Packard and both my Motors and Chiltons manuals. As far as votes are concerned, I torqued the head on my post war 356 with the threads dry and clean. 7 years later... still running.

I'm with JD, I've done or participated in dozens of Packard L8 headgasket jobs; always done with threads clean and dry, and never had a gasket failure that I can recall.

You all are awesome! Thank you so much. Now what's this "gasket paste"? Should I try to find some or just put the head gasket down as is.

I just received new head studs from Max Merritt so I'm all set to go.

Thanks again,
Crin

Permatex offers a very good copperized gasket product specifically recommended for head gaskets and happily it comes as an aerosol. Just hang the gasket and lightly spray both sides, then follow the directions as to wait time. This is a lot easier and better than using one of the brush-on gasket cements.

Long ago I read that the early stock car racers painted their head gaskets with aluminum paint. I have been doing that for years with fine results. I spray a sopping wet coat of Rustoleum aluminum (rattle can)on both sides and slap the gasket on as soon as it flashes off and is still tacky. It seems all that aluminum powder does the trick.

Can't thank you all enough for all the advice. Wish I had done all this when I first rebuilt the engine. It's all going back together this weekend and the carb should be ready in about two weeks - just in time to enjoy this 'wonderful' August Florida weather ...

Now who has a recommendation for a "Non belt driven, 6 volt, positive ground A/C system" that blows really cold ... lol ...

Thanks again,
Crin