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Posted by: ripper911 May 17 2014, 07:45 PM

What are the chances that I could just tighten the nuts which hold the heat exchangers on without pulling the studs out?

I'm about to set the car up for a morning valve adjustment and figured I'd spray the exhaust nuts with pb blaster and let it soak overnight in hopes of tightening them up.

Posted by: r_towle May 17 2014, 07:50 PM

When I have had the HE,s leak at the head, the only way it got them to stop was to remove the muffler, but leave on bolt holding the weight at the rear bracket.
Then I tighten up the heat exchangers...

After tight, I install the muffler again.

Rich

Posted by: kmwvmarip May 17 2014, 08:54 PM

I too recently took off the Heat exchangers and I had a stud come out. I suppose I would just double up on the nut and screw it back in again, right? Anything else to do while I am there?

Noob question prolly, but thanks in advance.

Posted by: ClayPerrine May 17 2014, 10:13 PM

Replace the copper gaskets that go between the heads and the heat exchangers. Be careful not to over tighten the nuts on the studs. It can cause the ears on the heat exchangers to bend, and pulled studs for the exhaust.

Remember, everything on these engines tightens up when they get hot.

Oh.. and be careful putting a stud back in the head. It is easy to over torque them and rip the threads out of the head.

Posted by: messix May 18 2014, 02:41 AM

use a 1/4 " drive ratchet.

harder to fuck it up that way.

Posted by: Allan May 18 2014, 05:46 AM

I screwed up the ears on my new to me ss exchangers using a 3/8" ratchet.

Posted by: ripper911 May 18 2014, 02:30 PM

I know what by it's so loud now...

My right side exchanger is only held on by one nut! the muffler end is missing nuts too. You can guess who worked on it last.

Posted by: Larmo63 May 18 2014, 02:37 PM

My car is backfiring on deceleration, not to hijack the thread, but could it be that I have loose HE's? It started when I put the stock muffler on....

Posted by: r_towle May 18 2014, 02:49 PM

Stop whining and go jack it up and fix it.


Rich

Posted by: ripper911 May 18 2014, 02:55 PM

It is jacked up... I don't have any nuts for it. Are the copper ones available from the flaps?

Posted by: r_towle May 18 2014, 03:08 PM

Just get normal nuts, they work fine

Posted by: ripper911 May 18 2014, 05:44 PM

Done and DONE! Sounds much better!

Posted by: ClayPerrine May 18 2014, 09:43 PM

There is a Mercedes nut used on their exhaust manifolds that work great on the 914 heat exchangers. They are treated so they don't seize to the studs, and they have a flange that fits the heat exchanger really well.

And for the muffler, use longer bolts and double nut them. The bolts won't back out that way, and you don't have to worry about pulled head studs because the bolt holding the muffler to the boomerang fell out.

Posted by: stugray May 18 2014, 10:42 PM

You can get a 8mm thread nut that takes a 12mm wrench instead of a 13mm.
Called a JIS nut

https://www.belmetric.com/metric-nuts-jis-small-wrench-nuts-c-3_58.html?gclid=CMXzgpCWt74CFceCfgodqSwA4A

It makes it easier to get a socket on with the smaller nut

Posted by: malcolm2 May 19 2014, 07:04 AM

It is a whole 'nother topic, but I think I remember that a lot of participants on this forum anneal the copper washers first. Am I remembering correctly?

Get out the torch and heat the washer to red hot. Let it cool in the air, then install. I barely made it out of metallurgy (30 years ago) so I would not consider myself very knowledgeable of all the microscopic reasons. But I do remember that the tuning fork feature of a heated washer went away vs. a non heated one.

Posted by: malcolm2 May 19 2014, 07:07 AM

I like the theory. That link did not have copper. I suppose there are lots of cars out there without copper nuts on the exhaust.

Posted by: Larmo63 May 19 2014, 07:07 AM

Are these copper washers available?

Posted by: stugray May 19 2014, 07:26 AM

I think there is some confusion above.
The copper "washers" are the gaskets, and yes they should be annealed with a torch before use.

http://www.pelicanparts.com/catalog/SuperCat/9144/POR_9144_EXHPIP_pg1.htm#item2