madmax442.com

What are you guys doing for head bolts on Gen 1 Olds 303, 324, 371, 394 engines? Reusing old ones, buying new from bolt manufacturers? Steel? Grade 5 or 8?
My '55 requires:
Per side:
Qty Description P/N
4 7/16-14 x 2 3/8 555661
10 7/16-14 x 4 7/16 561652
4 7/16-14 x 6 561653

Tedd Thompson

I reuse the old ones, never had a head problem. Some rigs that is a one time use part, but I've never heard that for a first generation Olds. Tedd

Olds64

x2

I reused all the hardware when rebuilding the 394 in my 64 Oldsmobile.

Wally

I looked into ARP bolts for my 371 bored 0.060 over but they don't make six inch bolts. I might call them and see if they can do studs instead. It's probably overkill but that's the way I roll.
Wally

Wally

I went through the ARP catalog and I'm seriously thinking about getting their 2 1/2" and 4 1/2" bolts and just use the original 6" bolts.
The cost is going to be about $150 for the ARP bolts. Peanuts compared to what I have invested in the 371 rebuild.
Wally

Run to Rund

My recommendation, based on builds of a 394 and multiple builds of a 400, is that the bolts are re-usable multiple times. Clean the threads and shoulders of the bolts, check for rust on them, and clean the threads in the block. Then oil with engine oil the shoulders and threads. If they come up to torque quickly and smoothly, they are good.

Wally

I agree except for oiling the threads. Some or possibly most of the bolts are open to the water jacket so I'll be using a thread sealer/locker on all them to make certain they don't leak or back off.
Wally

Run to Rund

OK it has been a long time since I built a 394 and I did not think about whether any of the bolts go into the water jacket. Back then, most people used Permatex #2 as a sealant.

Olds64

Better check the service manual. I just put heads on my 455 and it called for coating the head bolts with 30 weight oil before installing them.

Wally

A 455 is a big block, we're talking small block here.
The manual calls for thread sealant on the head bolts of the small block.
Wally

Olds64

Here's a good thread on small block vs. big block; as well as, generation 1 vs. generation 2 engines.

https://classicoldsmobile.com/forums...yes-no-165781/

@Tedd Thompson @Charlie Jones and @joe_padavano would be the ones to ask about sealant vs. oil on the head bolt threads. Otherwise, check the service manual.

joe_padavano

These are not torque-to-yield bolts. If they are not damaged or rust pitted you can reuse them indefinitely (OK, there IS a material fatigue limit, but if you are torquing them a million times or so, you have a bigger problem).