The Stovebolt Site Forums The Shop Area Engine Shop Copper Head Gasket Installation...

Hello fellow stovebolters! This is my first time using the site and it looks like a pretty good one. I am going to start off my first of probably many forum questions with a doozy: how in the heck do you properly install a copper head gasket???

I have a '51 235. The block has been decked and the head magnafluxed and tested for leaks. Everything is as perfect as it gets. BUT, when I filled her with antifreeze I noticed a seep leak along the spark plug side. I did a hot retorque and still the leak. I used permatex copper gasket spray on both sides of the gasket before installation, but not much at all (one thin coat a side) and did nothing special around the water ports.

I've heard stories of people using regular old silver spray paint as a sealant, but I'm not ready to test that experiment. I have another copper head gasket on the way and want to get it right this time. The gasket is a Best Gasket with composite sandwiched between two thin layers of copper. Should I spray more coats of copper sealant, use a different type of sealant, use rtv around the water ports, let it sit over night between torqueing increments??? And, is a hot retorque necessary? If anyone has step by step instructions, that would be greatly appreciated! Thanks, guys...

You wil find all sorts of opinions on head gasket installation, but the first and foremost thing to do is get everything CLEAN! With a freshly-decked block, and whatever cleaning the machine shop did during the magnaflux procedure, you've got that one covered!

While the spray sealers are OK, a lot of us oldtimers grew up using brush-on liquid sealers before spray sealers were invented. My favorite is Permatex Super 300. It's a dark brown, almost black thick liquid that seals seeps and stays tacky about 3 days past forever. The more common 3-D or 3-H Permatex brush-on doesn't seem to seal as well as Super 300. Give the top of the block a good even coat before installing the gasket, and brush another layer onto the top of the gasket before putting the head into place. Use either a little sealer or maybe anti-sieze compound on the head bolt threads, and put a little dab on the underside of each bolt head to help lubricate it during the torquing process and seal any coolant that might follow the bolt thread and creep out from under the bolt head. If a bolt doesn't need lubrication, it needs LocTite, and head bolts are definitely in the "lubricate" category. I like to do a 3-stage torquing process, warm the engine up, and retorque, unless I'm using a gasket that specifically says "do not retorque" in the installation instructions. Even then, I'm sorely tempted to do a hot retorque! Good luck!
Jerry

http://www.permatex.com/products/Au...atex_Super_300_Form-A-Gasket_Sealant.htm

funny...this is the third 235 I have heard of this happening on in the last 2 months. A head gasket leak along the spark plug side of the motor after installing a new gasket.

It happened when the shop installed mine...It happened to Adam (NSchonfe) and it happened to you.

When the mechanic at the shop that did mine took the first head gasket out he said he said it did not crush. It was still flat and smooth.

Is this a common problem or a QC problem at the gasket manufacturer?

Rich

Are copper head gaskets all that is available for the 235 and 216's? Last time I rebuilt a 235 or 261 I used Fel=Pro gasket set and the gasket sealed great and is still holding after nearly 30 years. But it wasn't a copper gasket. I didn't use any sealer on it, though I did use a sealer on the head bolts.

Thanks for the advice, Jerry. I'll definitely try the Super 300 sealant. But, after reading Rich and Roy Rodgers posts, I'm starting to worry about copper head gaskets for the 235s. Has anyone out there had success with a copper head gasket???

I should have tried that too. I never thought about the Super 300 sealant. My 235 ran fabulously, but it leaked like that too. I changed the head gasket 3 different times before finally giving up and sadly removed the 235 motor.



...I never thought it could have been my choice of sealant.
I always thought maybe the block was warped. Because I even tried having my head shaved perfectly flat by a machinist.

Man...if I only still had that motor. I would have tried a 4th time with that Super 300 sealant.

I just recently used a Fel-pro with no sealant at all. Torqued in three stages. Have not had the motor fired yet so not sure how well it has worked. I did not use any sealant on the head bolts though...am I looking at trouble for that?

What is the difference between the Permatex Super 300 and Permatex Aviation Form A Gasket No. 3?
Have any of you guys with trouble getting a head gasket to seal put a straight edge on the top of the block? How about running a thread cleaner in the head bolt threads in the block?
Just a couple thoughts. Thanks Don

When I take the head off again this weekend, I'll definitely run a straight edge over the block. It was decked, so I'm hoping all is good. I did not use any sealant on the head bolts last time, so that's probably contributing to the problem...

I am having the same problem with my Best brand copper head gasket. The composite material sandwiched between the two copper layers is exposed at the openings for some of the water/oil ports (exposed like the edges of the gasket). Could the material be absorbing the coolant eventually making it to the edge to create the seep leak? I'm going to replace mine in the next week too...

See if you can get a Felpro composite head gasket for your 235. Save a lot of head aches. I can't remember the last time I used a copper head gasket.

Well, I already have the copper gasket on the way, so I'm going to give it a shot again the way Hotrod Lincoln suggested and hope it works. I'll let you guys know what happens and thanks for all the responses...

Good luck. It should work fine as long as every thing is flat and clean.

Super 300 is vegetable based and the aviation NO. 3 what I've used is a modified resin.

http://www.permatex.com/documents/tds/Automotive/80018.pdf

http://www.permatex.com/documents/tds/Automotive/80057.pdf

I'm a firm believer in Fel-pro head gaskets after years of T&E with engines that tended to use up gaskets. If all the surfaces are properly trued and meticulously cleaned, Fel-pro eliminated all issues. In addition, I'll have to admit to spraying a light coat of silver paint on both sides of the gasket.

Fel-Pro offers a copper gasket Fel-Pro #7619C@ $26.00 for all you copper fans. I've also used the Fel-Pro #7619B composite @ $17.00 and an upper gasket set with copper gasket #HS7619C1 @ $40.00. Personally, I'd go for the #7619B and forget all the band-aid snake oil products. They have their place but I don't think they're necessary when using a quality gasket.

As for retorquing.....with modern Fel-Pro composite gaskets and quality machined components, I also 3 stage torque and have noted that my original torquing specs held.....making reetorquing a non-issue.

Dave

I've had success with the Fel-Pro copper head gasket and used no sealant.

I also removed the head twice and reused the old copper gasket with no problems.

Did you torque the head bolts in the correct sequence and a little at a time. And then the final torque at 70-80 ft lbs.

http://chevy.oldcarmanualproject.com/shop/1948_51truck/51ctsm0611.htm

Just got the copper gasket in the mail this morning, so I'm going to give it a shot this weekend. I have been using the proper head bolt torque sequence, but may I ask how to do a proper 3 Stage Torque??? (if I want to end at 75 ft lbs, should I torque 25 ft lbs at a time with a couple hours in between for settling)...

I wouldn't worry about the time in between torquing. But after the engine has run for its initial run and brought up to temp (engine expands), then let the engine cool (engine contracts)(just wait a day), re-torque the head bolts again.

Also, I would think 75 isn't enough...I would think upwards of 90.

What ever the book specs read are where I would torque them.

Thanks, guys. I'll go with the three stage torque and a hot re-torque and hope it doesn't leak at any point. I'll keep you guys updated on the results. Just out of curiosity, does anyone have experience with steel head gaskets for the 235? They are the same as the copper ones, only with two thin layers of steel...

The torque wrench will not be an effective indicator of tightness if the bolts don't run freely in to greater depth than where they were last insalled.It is not uncommon for unclean threads on the bolt or in the hole to make the fastener be tight to turn but not compressing the assembly.
So a wire brush or die nut to the male threads and a tap through the female threads before the assembly lube/sealer willassure proper clampup of the assembly.
A large flat file rubbed across the deck and head will show high places and raised areas which often occur at the bolt holes.
Any of the gaskets and sealers will probably be sufficient if you make the sealing surfaces flat and clean.
Just my two cnts worth.

Prosis shows 90 lbs/ft

Re torque after the engine is stone cold again...Not when it is hot.

perhaps the bolts are bottoming out.

are you using the old head bolts if so they might have gotten stretched with all the use there getting lately get you a new set of arp head bolts and a felpro gasket put a good coat of indian head shelack around the water jacket holes and do the 3 step torque sequence also put your bolts in the oven before you do your first torque that will let them expand and give you a head start on the second torque sequence

What would be the vendor and part number for a low-pressure 216/235 ARP head bolt set?

The Shop Manual shows 70-80 ft-lbs for 1951 engines (high pressure 235/261 engines are 90-95 ft-lbs).

I tighten the head bolts in correct order in three stages (maybe overkill but I've never had a leak). In this case, I'd go 25, then 50, then 75/80 ft-lbs.

We did one last week on an engine that had a leaking head gasket (the engine had been sitting since 1981). The head/block surfaces looked good. We lowered the head slowly and evenly onto the gasket/block (2 person job). The new Fel-Pro gasket is holding fine.

just call arp they are wonderful, but I don't think they have head bolts for a 235 I ended up using studs because they didn't have what bolts I needed. what ever the case call them and ask for Zac Kimball he will get you all set up.

ARP lists nothing for Chevrolet truck 6 cylinder head bolts prior to 1962. I see no need for ARP head bolts on 216/235/261 engines. However, since they were suggested above, I thought that poster might have information on their availability.

Cleaned original head bolts are reusable and have always worked fine for me. As suggested in the Shop Manuals, I lightly oil 1954 and newer head bolt threads before reusing them. I suppose this oiling would be OK on low-pressure engine head-bolts, but it is not described in the earlier Shop Manuals.
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