Help Please / SS Heat Exchangers, Someone else must have had this problem? Options

[MarkV]

I have had my ss heat exchangers off and back on three times. Can't seem to get them to seal. I used a file on them. Put a straight edge on them. Two different sets of new copper seal rings. The last time I even used a little copper RTV on them.

I bought them used on E-bay. Once they are bolted up I have to spread the drivers side about a 1/2" to line up the muffler hanger. They leak on both the drivers and passenger side.

What is the difference between 1.7 & 2.0 seal rings? I am using the the 1.7 rings because the are .010" thicker. Are there any other differences? (IMG:http://www.914world.com/bbs2/html/emoticons/screwy.gif)

They only leak on decel. I have them torqued to 17 ftlbs.

[dmenche914]

Try some blueing or even black felt tip pen ink on the copper washers, both sides, then tighten down again, then take off and see if the ink shows contact points and most importantly non-contact areas.

The 2.0 and 1.7/1.8 heat exchangers are interchangable on the engine, so long has you have the matching muffler and muffler hanger for the heat exchangers as they changed when the heat exchanger changed.

They can be a challenge to seal, as they have a much narrower sealing surface than the stock units.

[Allan]

I had the same problem when I first swapped mine with a set of stainless. I ended up filing the top of the tabs that the studs go through to give the pipes more protrusion into the seating area. It seemed to work as I no longer have a leak...

[MarkV]

QUOTE (Headrage @ Oct 16 2005, 01:38 PM)

I had the same problem when I first swapped mine with a set of stainless. I ended up filing the top of the tabs that the studs go through to give the pipes more protrusion into the seating area. It seemed to work as I no longer have a leak...

I filed those tabs. Are the tabs supposed to fit tight up against the head? Is 17 ftlbs tight enough.

They are barely leaking on 3 of the 4 cylinders. You can see the leak mark on the copper washer when you take the exchanger off.

[Allan]

QUOTE (MarkV @ Oct 16 2005, 03:48 PM)

I filed those tabs. Are the tabs supposed to fit tight up against the head?

No. That was my problem. The tabs were contacting the head and preventing the pipe from seating.

[ClayPerrine]

On the set I have on Betty's car the tabs keep bending. The loops that are welded parallel with the tube have a tendency to bend inward when tightened down.

I want to make a collar to fit around the tubes to replace the loops......

[MarkV]

The hoops don't appear to be bent.

Anybody know what the difference is between 2.0 & 1.7 copper seals.

[tommy914]

QUOTE (MarkV @ Oct 17 2005, 01:41 PM)

Anybody know what the difference is between 2.0 & 1.7 copper seals.

.3

(IMG:http://www.914world.com/bbs2/html/emoticons/blink.gif)

[nebreitling]

i don't know, but i'd be weary of putting more that 17lbs of torque on those studs. i can't remember the value off the top of my head, but i want to say it's like 12 or 13. do a search here.

broken exhaust studs really suck. a lot.

[aveale]

What about modifying the muffler hanger.

Worked for me, that way you are not bending the pipes that could cause the prob you have been having.

T

[mharrison]

QUOTE (nebreitling @ Oct 17 2005, 11:18 AM)

broken exhaust studs really suck. a lot.

Actually broken intake studs suck....broken exhaust studs blow! (IMG:http://www.914world.com/bbs2/html/emoticons/laugh.gif)

[Dave_Darling]

I got tired of the continual struggle to get my damn SSIs to fit. I had to hook two of the loops over the studs, and then shove on the end of the pipes to get the other two to line up. Usually in this process, the stupid copper gaskets fell out and I'd have to start over again.

So I removed them from the car again, figured out which way the pipes were out of line, and did a little "percussive maintenance" to them with my favorite bonking implement, the copper-faced mallet! A couple of trial fits, and then a whole bunch of filing the tops of the tubes, and it seems to fit nicely now!! I don't know when or how they got tweaked initially...

The 1.7/1.8 copper seals and the 2.0 ones are a slightly different shape. The seal goes with whatever type of head you have, so if you're putting a 1.7 exhaust on a 2.0 motor use the 2.0 exhaust gaskets. Or if your 2.0 motor has 1.8 heads, use the 1.7/1.8 gaskets.

--DD

[MarkV]

That might be part of my problem.

I am putting 2.0 heat exhangers on 2.0 heads using 1.7-1.8 copper washers. I didn't know that the 2.0 are shaped different. I thought the only difference was in the thickness. (IMG:http://www.914world.com/bbs2/html/emoticons/smash.gif)