Will the problems never stop....... well what would I do anyway if I wasn't constantly assembling and disassembling the engine?

I retrofitted 74 heat exchangers on my 76 2.0 Californian car. The exhaust is blowing pretty bad at the manifold gaskets, the stud nut are good and tight.

Can anyone give me some advice on the best solution to this problem.

Thanks again

The first trick is to check the flatness of each pair by running a very large flat file across the surface that mates directly to the head.

Second is to anneal the copper washers before you put them in to soften them

Third is to assemble both HES on the hangers and the heads loosely so they hang straight (no drooping on the muffler end)

Finally torque the nuts to (I think) 13-15 ft-lbs.

At this point you can check for leaks by connecting a shop vac (in blow mode) onto the muffler output. Then get under the car with a feather and probe the area where the gaskets are. You can find leaks by watching the feather.

Last drive it till it is fully warmed up then retorque the nuts while still warm and if you did not use locking nuts, double-nut them at this point

The hardest part when working upside down is to get the gaskets in square.

Each time the exchangers come off you should anneal or replace the gaskets if they have been heat cycled

Did you reuse your gaskets and fail to anneal them?

Once again thanks for the help guys, I would be pretty stuck without this forum and your help

The gasket came straight out of the gasket kit, I guess they are delivered annaled?

My worry is the exchangers I bought were not new I think they are a bit distorted as they did not line up with the muffler/hanger.

Gaskets are not delivered annealed. Take a torch to them until the turn blueish and reinstall.

I like to glue a sheet of 120 grit to a flat piece of plate steel w/ spray adhesive then slide the header ends carefully across, Flip it to reveal any low spots. Unless they are trashed out you can true them this way taking your time.

I went through this a couple of months ago. They didn't make this process easy on these cars!

This thread has some additional info and advice people gave me before I did it: Heat Exchanger Install

I did anneal the gaskets. I used a propane torch, got 'em sort of red, and then dunked them in a glass of water. You can tell when it's annealed because when you drop them on the table they make a dull "clunk" noise instead of a ringing noise.

I found the hardest part during the actual install was keeping the gasket positioned correctly on top of the HE as I was trying to fit the HE onto the studs. Use a flash light and try to ensure you can see gasket on each side of the HE when it's in place. I used some sticky copper sealing stuff that was recommended by someone. It kept the gaskets in place somewhat during this process. I also found it helped to have a 1/4 socket and wobble / flexible extension.

When all was said and done the install went decently well. For my first time I think it turned out reasonably well thanks to the advice I got.

Good luck.

Thanks for the help guys it is much appreciated.

Wasn't there a discussion not too long ago about to anneal or not to anneal? I seem to recall some fairly experienced folks saying annealing is not necessary. Am I wrong?

Put a couple dabs of grease on the gaskets and put them up in the port first, instead of laying them on the header.

Also, tighten the nuts a little at a time, moving back and forth. If you tighten one side more than the other too much, it can sometimes actually stop the pipe from sitting flat. I also like to grab the whole heat exchanger and jiggle it, to help settle the pipes on the gasket. Just don't jiggle until it's close enough to keep the gaskets from dropping out. I jiggle just the couple turns before the nuts are tight.

I've recently joined the annealing team. I never tried it until a few weeks ago, and was very surprised how soft it made them.

So, which is worse, jiggling too much or jiggling not enough? This tread reminds me of an old girlfriend, Cindy Annealing. Could she ever jiggle!!

Really easy to do. I use this technique on my turbo/manifold gasket. Seals up great. The soft copper makes up for minor surface imperfections.


https://www.youtube.com/watch?v=9VcqBprVP6o

I had the same problem after an install. Turns out the gasket wasn't seated properly on the header. Removed the header and superglued the gasket to the head to hold it in place and reinstalled the header. No leaks.