The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1967 - 1972 Chevrolet & GMC Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 03-21-2024, 12:00 PM   #1
Loose Screw
Registered User
 
Loose Screw's Avatar
 
Join Date: Jan 2024
Location: EL PASO
Posts: 88
Old Style "Rams Horns" Exhaust Flange Donut Gasket

My exhaust manifold does have a small rim about half an inch down inside the outlet to exhaust pipe.
I've noticed that some exhaust flanges have a metal collar built into them.

I put your typical donut in there (no collar) and it still sounds like it's got a leak. Yeah I did put new nuts and bolts and kept cranking on them but it still sounds like there's a leak and the gasket to head is new. I'm pretty sure it's that donut...

What do you all use on those old rams horns?

TIA
Loose Screw is offline   Reply With Quote
Old 03-21-2024, 02:06 PM   #2
truckster
Senior Member
 
truckster's Avatar
 
Join Date: Jan 2001
Location: Orem, Utah
Posts: 7,798
Re: Old Style "Rams Horns" Exhaust Flange Donut Gasket

I used a donut with a collar. No leaks after a couple of years.
__________________
I have sworn upon the altar of God, eternal hostility against every form of tyranny over the mind of man. - Thomas Jefferson
truckster is offline   Reply With Quote
Old 03-21-2024, 03:35 PM   #3
jaros44sr
Registered User
 
jaros44sr's Avatar
 
Join Date: May 2006
Location: Philadelphia, Pa. 19454
Posts: 9,421
Re: Old Style "Rams Horns" Exhaust Flange Donut Gasket

New studs and brass nuts works best at drawing the two pipes together and new collars

I've tried the non sleeve type, but the metal sleeve seems to me work best
__________________
Semper Fi...Uncle Sam, you da man

All parts offered to help are free, unless otherwise noted

Dont try this stuff in my build thread, unless you have 55 years of mechanical OTJ training
SAFETY FIRST

AS usual, off topic

They say your mind goes second, can't remember the first


Jim

Last edited by jaros44sr; 03-21-2024 at 06:41 PM.
jaros44sr is offline   Reply With Quote
Old 03-21-2024, 08:22 PM   #4
Steeveedee
Who Changed This?
 
Steeveedee's Avatar
 
Join Date: Jan 2013
Location: Simi Valley, CA
Posts: 10,092
Re: Old Style "Rams Horns" Exhaust Flange Donut Gasket

At the age of the manifold, it may well be pitted enough to allow a leak, even with the doughnut. I had a Buick like that, and used some exhaust system sealer. Of course, it was metal to metal, (which gaskets still didn't help). I got it at O'Reillys.
__________________
~Steven

'70 Chevy 3/4T Longhorn CST 402/400/3.56 Custom Camper

Simi Valley, CA
Steeveedee is offline   Reply With Quote
Old 03-22-2024, 11:19 AM   #5
kwmech
Senior Member
 
Join Date: Mar 2003
Location: Colfax-California
Posts: 8,391
Re: Old Style "Rams Horns" Exhaust Flange Donut Gasket

Are you sure it is not leaking at the cyl head in the center? Was the manifold flat when you installed it?
kwmech is offline   Reply With Quote
Old 03-25-2024, 01:56 AM   #6
Loose Screw
Registered User
 
Loose Screw's Avatar
 
Join Date: Jan 2024
Location: EL PASO
Posts: 88
Re: Old Style "Rams Horns" Exhaust Flange Donut Gasket

I think I got it. I smoothed out (to 1000 grit) head to to manifold and manifold to tailpipe surfaces and torqued down. It kind of sounds like I got it. Once I get those crappy flow masters that the "artist" put on there thrown away I'll be able to hear better what's going on...
Loose Screw is offline   Reply With Quote
Reply

Bookmarks


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 04:43 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com