Exhaust Pipe Flange/Ring installation

SweetSix

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I have a '65 Ranchero with a 200. I am replacing the worn out, leaking exhaust pipe flange/ring which goes between the exhaust manifold and exhaust pipe. I have the flange, #C3OZ-9450-A, and ready to install. Is this flange installed with any kind of high-temp sealant or is it installed with just the flange itself, "dry"? I replaced this flange "dry" once before a couple years ago and it's leaking badly already.
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B RON CO

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Hi, 50 years ago there was no sealant for high temp parts.
Now I've used both high temp silicone and high temp muffler and tailpipe cement with good results.
Read about the products and decide what you like.
I know the exhaust guy in my town likes the permatex muffler sealer on all his jobs.
Good luck
 

chad

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as usual "Pic's wortha...".
Can't quite tell where ur at.

If U have what we call the donut (a round sided continuous circle like a pony tail rubber band) that's correct for the end of the down pipe offa the exh manifold. It just lays in there as I remember & is pressed (held ) in place as the 2 bolts are tightened down. Perhaps U did not come back after several heat cycles to snug up. Heat expands (then it cools, shrinks) until loose. Proper installation techniques require U come back for this several times.
I believe some (not mine) have 2 flat surfaces meeting (flange) w/a lill circular indent inside (more modern). That takes a flat gasket. Same need often, a return 2 to 3 X for a snug up after heat cycles.
More detailed explanations = more applicable answs...
 

DoctorC

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I'm having a similar problem of a massive exhaust leak. The compression plate that holds the exhaust tube to the manifold is installed tight, but crooked. The attached pic shows the larger sided gap, the opposite being about 1/2 the size. After a few tries and a couple days soaking, I was able to loosen the bolts and remove the plate. The donut is a series of loose metal rings (apparently the same as above, after all the blue stuff is blasted off.

exhaust-reduced.jpg

I think the PO had a buddy crap weld the exhaust together and the coupling angle is not perfect (and one of the welds has the wire still sticking out of it). Should I drop a new donut in there, massage it to as straight as possible and add sealant and bolt as tight as possible, or do i need to motivate (with a hammer) the tube into straight alignment for it to seal?

I have tubular headers to be installed... but I want to get it all running and drive around for a while before breaking the head bolts and filling the swear jar.

Any suggestions / guidance is much appreciated.
 

chad

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chad":28551gyv said:
If U have what we call the donut (a round sided continuous circle like a pony tail rubber band) that's correct for the end of the down pipe offa the exh manifold. It just lays in there as I remember & is pressed (held ) in place as the 2 bolts are tightened down.
It's kinda: go / no go situation.
If there is distortion there - no amounta paste is gunna fix it.
That stuff just falls out ina few days.
I'm thinkin the new system 'll fix ur concerns. But, if U must AND ur a good tin knocker
U could look at the cast part of the mate, heat the exhaust pipe cherry red, take it to the anvil &
try'm match that malleable prt to the cast. Pretty intricate in the exh pipe. The OP killed ur chance ona
good mate by mo (& possibly yrs) of heat while ina misaligned match...
 

bubba22349

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In your above picture you can cearly see that the one manifold stud is not going into the manifold straight (maybe both?). In any case you wouldn't get a good seal unless these studs are installed correctly into the manifold so that it pulls the head pipe and its seal straight into the manifold. The fix is to drill out the manifold mounting holes at 90 dergees to the manifold flange surface install oversize studs / helicoil or go with your set of headers. Good luck (y) :nod:
 

DoctorC

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Thanks for all the feedback. Sounds like I'm in a pretty pickle.

I'll check the alignment tonight of the bolts, but I think you're right bubba, they're not 90 degrees to the mating surface. That, for a temporary fix, might be coaxable with a hammer. But, maybe with a friends help, I can get it to mate better than it was. One pushes from below, the other tightens evenly the bolts. Cuz I aint gonna pull the exhaust manifold to fix the bolts. If I pull it, it's to put on the new VI 2-2s I bought =)
 

bubba22349

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You could try using a pipe and gently persuade it a little heat could help too. Good luck (y) :nod:
 

DoctorC

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chad

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"A picture is worth a thousand words"
But I don't think you want that flat 1.
Yours takes the 'donut' I believe...
:?:
ie for the 1st exh. down pipe after the exh manny.
 

DoctorC

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So I just picked it up and it's a donut, same general shape as the blue one I got from CJPP. The big difference is that this is solid metal. The blue donut is a bunch of thin metal rings held together with blue stuff.

That means the blue one is flexible, a little. The solid metal one will not be.

I'll upload pics of the decrepit falling apart blue one and the new solid one when i get home.

DrC
 

DoctorC

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Heres the solid gasket compared to the old ratty falling apart blue donut:
gasket-1.jpg

Here's a close up compare:
gasket-2.jpg

I installed the gasket and it seems to work great! I did not add any sealant but I bought it in case dry was leaky.
 

chad

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yup, dats it.
Wuz a flat 1 round here, don't C it now (wuz wrong).
 

DoctorC

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DoctorC":fwd7e906 said:
I installed the gasket and it seems to work great! I did not add any sealant but I bought it in case dry was leaky.

Ok,l take that back. After about 500 miles it started leaking again albeit not as bad as before. Took it to the local muffler shop and had them make a new coupling and install a y pipe. Turns out PO took a straight pipe and make a kind of lopsided T pipe to turn the single into a dual exhaust. Horrible job. For 150 bucks he cut off the T and installed a proper Y and re-did the hookup to the manifold.

Turns out the inner part of the connector was too tall and not letting the gasket make full contact.

Life is better now =)
I had him install one of the blue gaskets to see how it holds up.
 
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