tips/tricks for fitting stainless steel heat exchangers Options

[jmargush]

Getting ready to attach the heat changers to my heads that came from HAM.

Doesn't appear that they are going fit right up easily.

Does anybody have any tips or tricks for getting them to fit?

Do they normally require some convincing to go on?

[stugray]

one trick I learned last time around:

The new step studs i got from Belmetric were not perfectly straight.
So as I ran them in I had to mark them so I could set the clocking correctly or I could not get the flanges to go over them consistently.

Stu

[messix]

loosely attach everything, the h/e muffler bracket, muffler.

then progressively tighten the h/e with a 1/4 ratchet handle so you don't get tempted to over tighten the nuts. then tighten the muffler and then the bracket.

before you take it off the jack stands start it up and listen for leaks [you''ll have some] then loosen and adjust for the leaks.

if a leak is on one of the h/e stub connections you can loosen one nut and tighten the other to get it to seal.

[r_towle]

three fitment issues I have had.
At the studs, fix is to dremel out the loop on the HE to make it line up.
I have never seen a new stud that is bent, but plenty of crooked holes in heads, cross threaded studs, and poor insert alignment.
Easiest to tweak the HE at that point...
I have had to remove and move on loop on one HE....the rest have been close enough to make fit.

At the head, fix is to ensure both parts of the HE that touch the head are flat and on the same plane...
Heat up and anneal the copper gasket to make it crush better.

At the muffler, this just takes some twisting to get things to line up perfectly or the gasket will leak.
I have used two gaskets per side on one car...just cause it works.

I bolt up the HE to the heads while hanging the rear loose on the bracket only, with no muffler.
Only after I am done, tight and torqued to the head do I introduce the weight of the muffler into the mix.

oh, as stated in the previous post, it will leak the first time.
If it leaks at the head,...remove the muffler and fix that issue with no weight on it.

Rich

[reharvey]

Use heavy duty washers under the nuts that go on the head studs.

[bigkensteele]

I found a great tip from McMark - use a flashlight to insure that you can see the copper gasket ALL THE WAY AROUND each tube when tightening. This will insure that the tube is resting entirely on the gasket.

I had a really bad leak that was caused by the tube resting on the ledge of the head (the gaskets are slightly recessed when seated). Following Mark's advice was the ticket.

[jmargush]

Thanks guys all great advice

Right now I am looking at having to fuss with the loops to even get the HE to go on.

[rhodyguy]

#1. spray current good studs with something like pbblaster and clean ALL of the visible threads of rust. clean them coat the threads with milk of magnesia ala raby. it works. did all of the old nuts come off without turning a stud out?

[Java2570]

Thanks guys all great advice

Right now I am looking at having to fuss with the loops to even get the HE to go on.

Yeah, the SSI stud flanges aren't quite the same as the stock units or at least that's how mine are. The set I bought used, I was able to mount the passenger side one but have never been able to do the driver's side. I'm going to attack the flanges with a dremel and see if I can get it to work at some point. I'm sure my studs are slightly off on that head. It's been frustrating to say the least!

[914_teener]

three fitment issues I have had.
At the studs, fix is to dremel out the loop on the HE to make it line up.
I have never seen a new stud that is bent, but plenty of crooked holes in heads, cross threaded studs, and poor insert alignment.
Easiest to tweak the HE at that point...
I have had to remove and move on loop on one HE....the rest have been close enough to make fit.

At the head, fix is to ensure both parts of the HE that touch the head are flat and on the same plane...
Heat up and anneal the copper gasket to make it crush better.

At the muffler, this just takes some twisting to get things to line up perfectly or the gasket will leak.
I have used two gaskets per side on one car...just cause it works.

I bolt up the HE to the heads while hanging the rear loose on the bracket only, with no muffler.
Only after I am done, tight and torqued to the head do I introduce the weight of the muffler into the mix.

oh, as stated in the previous post, it will leak the first time.
If it leaks at the head,...remove the muffler and fix that issue with no weight on it.

Rich

(IMG:style_emoticons/default/agree.gif)

Leaned this trick to get them to seal:

1. Apply a thin coat of copper based RTV to each gasket.
2. Pop the gaskets in the heads and let them sit for a bit.
3. Apply another bead of RTV...this time let your finger create a bead and let it set up a bit.
4. Fit up the HE's and torque them to spec by evenly tightening them.

Note: Make sure they will fit up prior....which is what stage you are at now.

[jmargush]

#1. spray current good studs with something like pbblaster and clean ALL of the visible threads of rust. clean them coat the threads with milk of magnesia ala raby. it works. did all of the old nuts come off without turning a stud out?

the heads are basically brand new as they came from Hoffman Automotive.

[jmargush]

three fitment issues I have had.
At the studs, fix is to dremel out the loop on the HE to make it line up.
I have never seen a new stud that is bent, but plenty of crooked holes in heads, cross threaded studs, and poor insert alignment.
Easiest to tweak the HE at that point...
I have had to remove and move on loop on one HE....the rest have been close enough to make fit.

At the head, fix is to ensure both parts of the HE that touch the head are flat and on the same plane...
Heat up and anneal the copper gasket to make it crush better.

At the muffler, this just takes some twisting to get things to line up perfectly or the gasket will leak.
I have used two gaskets per side on one car...just cause it works.

I bolt up the HE to the heads while hanging the rear loose on the bracket only, with no muffler.
Only after I am done, tight and torqued to the head do I introduce the weight of the muffler into the mix.

oh, as stated in the previous post, it will leak the first time.
If it leaks at the head,...remove the muffler and fix that issue with no weight on it.

Rich

(IMG:style_emoticons/default/agree.gif)

Leaned this trick to get them to seal:

1. Apply a thin coat of copper based RTV to each gasket.
2. Pop the gaskets in the heads and let them sit for a bit.
3. Apply another bead of RTV...this time let your finger create a bead and let it set up a bit.
4. Fit up the HE's and torque them to spec by evenly tightening them.

Note: Make sure they will fit up prior....which is what stage you are at now.

Engine is still on the stand
I want to try to assemble the exhaust while it is on the stand since it will be so much easier to get everything to fit right instead of working overhead

[Mblizzard]

More of a sealing tip than a fitting one. I have always made it a point to ensure that the tops of the heat exchanger pipes were true by using a straight edge and filing across both at the same time (16 inch file). Use a sharpie to verify that your filing is true. If you file the tops you will also have to remove the same amount from the top of the bolt ears to ensure that they don't contact the head and that there is ample space between the ear and head to allow the copper ring to actually crush.

[eyesright]

Engine is still on the stand
I want to try to assemble the exhaust while it is on the stand since it will be so much easier to get everything to fit right instead of working overhead
[/quote]
Good,...you are doing it the easy way where you can see all the spots where the flange binds on the studs (maybe) or the head recess.

Len did my heads too and I wondered if the studs were skewed when I couldn't get the pipes to fit up into the recess without binding. Upside down, under the car, low jackstand clearence, poor light....I finally could see that the pipes/flanges were binding against the recess in the heads. Some filing on the side of the flange and they slipped right into place. The studs were perfect...of course.

Early or late HE's (mine's a '76) keep filing until they slide right on and don't forget to flatten the mating surface with a file or stone.

Good luck.

[rhodyguy]

don't file anymore off than you need too. use the sharpie as mike suggested and the file should be large enough to dress both pipes on one side at the same time. VERY light passes. i'd still dress the studs as i mentioned.