manifold donut gasket help please
Thread Starter
Instructor
Joined: Jan 2009
Posts: 145
Likes: 1
From: Cudjoe Key Florida
manifold donut gasket help please
ok guys i need some help i dont know what im doing wrong never had this much trouble with a donut gasket.
i have the stock manifolds on my 71 and the passenger side donut gasket ive replaced and tightened up put lock washers on and locktite and it still keeps getting loose.
when i replaced it they had 2 different donut gaskets one was steel and one was the regular i guess espestes gasket one i got the regular one thinking the surface in there is no way perfect enough to seal with a smooth steel surface.
do i need the steel one ?
whats the deal with this thing its a real pain in the a@# to keep getting under there to tighten it up.
oh btw the drivers side is fine no problem replaced it tightened it up drove a bit let it cool tightened it more never a problem.
i have the stock manifolds on my 71 and the passenger side donut gasket ive replaced and tightened up put lock washers on and locktite and it still keeps getting loose.
when i replaced it they had 2 different donut gaskets one was steel and one was the regular i guess espestes gasket one i got the regular one thinking the surface in there is no way perfect enough to seal with a smooth steel surface.
do i need the steel one ?
whats the deal with this thing its a real pain in the a@# to keep getting under there to tighten it up.
oh btw the drivers side is fine no problem replaced it tightened it up drove a bit let it cool tightened it more never a problem.
Race Director
Joined: Nov 2002
Posts: 12,142
Likes: 54
From: Taylor Michigan
The better gasket is the Felpro brand. The steel gasket was used by Ford several years ago. I have sold both the fiber and steel. The fiber is more forgiving. The only way I see you having a problem with the gasket [either one} is that you are not getting the pipe and manifold lined up correctly and then vibration of road, engine or whatever allows the pipe to move. Try a muffler shop to get it up in the air and i`ll bet they can resolve your problem very inexpensively and maybe for nothing if presented to them correctly.....
Melting Slicks
Joined: Mar 2009
Posts: 3,126
Likes: 15
try an all steel self locking nut on the studs. the lock washers and lock tight may not be able to handle the heat and thermal expansion and contraction. some times the original lock nuts are damaged if they are removed with an impact gun and will feel tight when cold but loosen when hot. mds...
Le Mans Master
Joined: Sep 2003
Posts: 8,812
Likes: 2,029
From: eastern NC
I only asked because the passenger side manifold is flat on the bottom to match the top of the heat riser. A flat gasket goes between them. The bottom of the heat riser has the taper to accept the donut. If the heat riser were installed upside down there would be no taper and the donut would have difficulty seating properly.
Another thing is to be sure the EXHAUST DONUT ALIGNMENT SLEEVE that holds the donut in place is in good shape to properly position the donut.
Good luck... GUSTO
Another thing is to be sure the EXHAUST DONUT ALIGNMENT SLEEVE that holds the donut in place is in good shape to properly position the donut.
Good luck... GUSTO
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Le Mans Master
Joined: Sep 2000
Posts: 9,078
Likes: 7
From: DFW TX
Cruise-In VII Veteran
St. Jude Donor '07
I only asked because the passenger side manifold is flat on the bottom to match the top of the heat riser. A flat gasket goes between them. The bottom of the heat riser has the taper to accept the donut. If the heat riser were installed upside down there would be no taper and the donut would have difficulty seating properly.
Another thing is to be sure the EXHAUST DONUT ALIGNMENT SLEEVE that holds the donut in place is in good shape to properly position the donut.
Good luck... GUSTO
Another thing is to be sure the EXHAUST DONUT ALIGNMENT SLEEVE that holds the donut in place is in good shape to properly position the donut.
Good luck... GUSTO
This sounds like your problem.
Thread Starter
Instructor
Joined: Jan 2009
Posts: 145
Likes: 1
From: Cudjoe Key Florida
i can get my hand down in ther when its running and feel where its coming from below the riser and i can get it tightened up and its great and dosent leak for about 2 weeks then i start to hear it leaking again so i go to my friends lift and tighten it again
my friend even checked what your saying to see if it was above the riser while it was on the lift running and he had a welding glove on and thats when we replaced the donut.
i guess ill take it to a muffler shop tomarrow and hope they dont break the studs off with a impact
my friend even checked what your saying to see if it was above the riser while it was on the lift running and he had a welding glove on and thats when we replaced the donut.
i guess ill take it to a muffler shop tomarrow and hope they dont break the studs off with a impact
Le Mans Master
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
You can also use tall brass nuts on the studs. They won't seize on the studs, and there's enough extra threads they usually don't back off. If the sleeve is inside the donut and everything is reasonably square, you'll be done with this problem.
Drifting
Joined: Jul 2008
Posts: 1,873
Likes: 27
From: Sonora CA
I agree with MDS, you should not usr lock washers, use the steel lock nuts. Also check to make sure that the studs are not backing out ........ I have seen manifolds where the threads were all shot and the studs were not holding.
Steve
Steve
Senior Member since 1492
Joined: Aug 2000
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From: Just because I'm paranoid doesn't mean people aren't out to get me...
St. Jude Donor '09
I only asked because the passenger side manifold is flat on the bottom to match the top of the heat riser. A flat gasket goes between them. The bottom of the heat riser has the taper to accept the donut. If the heat riser were installed upside down there would be no taper and the donut would have difficulty seating properly.
Another thing is to be sure the EXHAUST DONUT ALIGNMENT SLEEVE that holds the donut in place is in good shape to properly position the donut.
Good luck... GUSTO
Another thing is to be sure the EXHAUST DONUT ALIGNMENT SLEEVE that holds the donut in place is in good shape to properly position the donut.
Good luck... GUSTO
I thought those were for BB's? I didn't use these when I had a SB.
Race Director
Joined: May 2006
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From: Dayton, Ohio
Thread Starter
Instructor
Joined: Jan 2009
Posts: 145
Likes: 1
From: Cudjoe Key Florida
well i took it to the local muffler shop and there was a guy there that said oh ya we can fix that right up for ya no problem .................i said im afraid if you hit it with a impact it might break the stud..............he said oh no we aint gonna break it.
they took it apart cleaned it all up with a wire wheel and put back togather with new gasket i already had and put new locking nuts on it and well its not leaking as of yet we will see in 2 weeks
they took it apart cleaned it all up with a wire wheel and put back togather with new gasket i already had and put new locking nuts on it and well its not leaking as of yet we will see in 2 weeks
