I used mopar # 1851579, original steel shim gaskets for the smaller 383 bore. Surprisingly several places had them, check ebay.

 

Not sure of the max bore, was fine for my 30 over 383. Thickness is around 0.020".

 

When I've used steel shim gaskets, I've always given them two thin coats of "copper kote" spray, so that the thickness is now a whopping 0.021".

This prevents weeps and seeps of oil or coolant. Let both coats dry thoroughly, BTW.

 

Why do you have to pull the head? It is usually not excessively hard to fix the broken stud with the head still in the car, but some are harder to get to than others...........

Which stud is broken?

First choice is welding a nut to the broken stud. Second choice is drilling it out using a jig for locating the hole and using a tight right angle drill.

 

If you do decide to pull those heads, please resist the Irresistible Urge to scrape the carbon buildup off your pistons:

1) there is absolutely no reason to do it, other than that Irresistible Urge.
2) you really, really don't want that crud on your rings and sides of the piston.

As for the crud from cleaning the block surface that goes "down the hole", you'll want to shopvac all that stuff out, of course.

 

I was just wondering whether the use of copper kote spray or something equivalent was ever used by the factory - I have never seen any evidence that it ever was and yet I have seen very few failed steel factory gaskets except for not keeping the coolant reasonably free of rust over time.

 

I don't think I've personally taken apart a virgin Detroit engine that had a true steel shim gasket such as the one shown in Post #2. They have always been some sort of reinforced composite construction in my experience. For street Mopars, the FSM points to a composite gasket with the word "compressed".




But if a true steel shim gasket was used in some Detroit hi-perf engine, remember that the block and heads were freshly machined and dead-flat, so a coating might not have been necessary. Regardless, I have never NOT used K&W Copper Coat on a steel shim item.

 

I am not criticizing your use of the gasket compound but was wondering why Chrysler didn't use it - probably cost a couple cents more so it was nixed? I was just wondering whether it really provides a significant benefit or not? When I rebuild an engine I always check the flatness of the mating surfaces.

The steel shim gaskets have raised portions on them so that when compressed between the heads and block, they become compressed steel head gaskets, not composite. I have never seen an original factory B engine that didn't come with a single steel head gasket for each head, never a composite one in the 1950s - early 1970s at least.

 

Oh, I didn't take it as criticism at all, just useful discussion. My point is that regardless of the flatness of the mating surfaces, I'm talking micro-imperfections and the oil/coolant weeps that can be easily remedied with that few cents worth of copper coat. And yes, I'm quite familiar with the embossed raised portions of the gasket. The many small blocks that I built had the awful 4-bolt per cylinder architecture....I was VERY careful about sealing, multiple steps of torqing, retorqing after run-in, etc.

I never took note of what an OEM gasket was, assuming I've ever disassembled a virgin motor of any make (I'm sure I have, but....). But I've always been under the impression that OEM stuff was a steel-core laminate.

 

Don't forget that steel shim gaskets have to be re-torqued after a short period, 50 miles comes to mind, (may be less).

 

Exactly. And that's why I seriously doubt that OEM was true steel-shim gaskets. They were a laminated steel sandwich somethingorother.

 

Every original mopar 60's motor I've seen has had steel shim head gaskets. This also applies to every 60's head gasket part number I've seen. Believe the laminates started sometime in the 1970's during the smog era. It was an easy way to drop the compression a bit. Also don't know where this retorqiing thing is coming from, not necessary with these gaskets. I've never done it & have never had a leak. If that were the case then every new car back then would have had to be returned quickly to the dealer and it would have been in every service manual.

 

The factory service manual, for B engines at least, suggests that a light sealer coating be applied to the new steel head gaskets but does not mention the need to retorque the head bolts after a certain number of miles. It does advise that the head bolt threads be clean and a light coating of oil be on them so they go into the threads of the engine easily - you should be able to thread the bolts in most of the way by hand. As such achieving the initial and secondary torque settings should be very reliable such that retorquing the bolts should not be necessary. If folks do not use the recommended practice and do not clean the bolts and threads carefully, maybe then it would be wise to check things again after some initial miles. Otherwise it shouldn't be necessary at least for a B engine.

The factory only used single layer (shim) steel head gaskets and no form of composite - if they did, please show me one, especially one that is only .020" thick - there was no laminate.

 

Years ago I looked at most if not all the various 60's and some 70's head gaskets for small & big blocks & even slants. As stated the early ones were all stamped steel (one exception below) but at some time in the 70's they did go with composites & you have to be wary of superseded part #s. There were some part # changes where they slightly changed water passage hole sizes but nothing significant. The thing they did do was have gasket bores that more closely matched the actual engine bore. Later when mopar performance put out their replacement gaskets they were one size fits all with a huge bore. You will lose a small amount of compression with those on the smaller bore engines.

The one exception to the rule was the aluminum slant, they actually used a copper shim gasket! I found one of those for a local guy, believe it was a NORS Fel Pro, very hard to find. The aluminum slant is a really bizarre motor, the block is actually die stamped rather than cast. Just imagine the size of the tooling to do that!

Believe the factory used some type of material (very lightly) as a sealant originally. it appears to be a sort of brown color, not the copper stuff that's commonly used now. The factory block/ head surface finish is very smooth & you have to duplicate that if you want to ensure no leaks.

 

I've disassembled multiple '60s big blocks that were absolutely never taken apart before, and they were all true steel shim gaskets.