exhaust manifold leak...need to replace gaskets
09-08-2017, 08:26 AM
#1
Le Mans Master
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St. Jude Donor '17, '19
exhaust manifold leak...need to replace gaskets
Hey Guys,
While trying to figure out the exhaust issue I am having I discovered I need to replace my exhaust manifold seals. I have never done this and my friend told me he won't help because of fear of breaking a bolt.
Is there anyone in Indiana who has done this who could help? Trying to leverage experience so I don't end up causing a bigger problem. Any suggestions?
A body shop quoted me $600 for the job. Seems really high for a few gaskets. Looking to do this myself if it is a good idea.
Thanks.
While trying to figure out the exhaust issue I am having I discovered I need to replace my exhaust manifold seals. I have never done this and my friend told me he won't help because of fear of breaking a bolt.
Is there anyone in Indiana who has done this who could help? Trying to leverage experience so I don't end up causing a bigger problem. Any suggestions?
A body shop quoted me $600 for the job. Seems really high for a few gaskets. Looking to do this myself if it is a good idea.
Thanks.
09-08-2017, 10:24 AM
#7
Race Director
09-08-2017, 10:33 AM
#8
Safety Car
the problem might be the donut from the pipe to the manifold, that is where the leaks usually are. you might get away with not removing the manifold.
if a bolt breaks then buy a new manifold, its cheaper than the hours long repair. there's thousands of them out on the market.
if a bolt breaks then buy a new manifold, its cheaper than the hours long repair. there's thousands of them out on the market.
09-08-2017, 10:34 AM
#9
Racer
Just took the exhaust manifolds off an original '75 350 that had never been disassembled. Bolts were in there like nobody's business. Sprayed them every day for 4 days with PB Blaster letting them sit and they came right out. There was some sort of gasket material in there, almost like asbestos or something fibrous.
09-08-2017, 10:39 AM
#10
Race Director
the problem might be the donut from the pipe to the manifold, that is where the leaks usually are. you might get away with not removing the manifold.
if a bolt breaks then buy a new manifold, its cheaper than the hours long repair. there's thousands of them out on the market.
if a bolt breaks then buy a new manifold, its cheaper than the hours long repair. there's thousands of them out on the market.
Just took the exhaust manifolds off an original '75 350 that had never been disassembled. Bolts were in there like nobody's business. Sprayed them every day for 4 days with PB Blaster letting them sit and they came right out. There was some sort of gasket material in there, almost like asbestos or something fibrous.
09-08-2017, 10:58 AM
#11
Le Mans Master
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St. Jude Donor '17, '19
the problem might be the donut from the pipe to the manifold, that is where the leaks usually are. you might get away with not removing the manifold.
if a bolt breaks then buy a new manifold, its cheaper than the hours long repair. there's thousands of them out on the market.
if a bolt breaks then buy a new manifold, its cheaper than the hours long repair. there's thousands of them out on the market.
Wouldn't I have to disassemble the whole top part of the engine to do that?
09-08-2017, 10:59 AM
#12
Le Mans Master
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St. Jude Donor '17, '19
Does anyone have a diagram of where the bolts are located? I have an AIM but I still need to find it. Moved last year and its in box somewhere.
09-08-2017, 11:57 AM
#13
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Hi s,
No gaskets between the heads and manifolds originally.
A TOTAL of 12 bolts.
6 each side.
Here're the rear 3 on the right side.
Regards,
Alan
If you're unsure where the exhaust manifold bolts are, it might be wise to have someone help you with this.
No gaskets between the heads and manifolds originally.
A TOTAL of 12 bolts.
6 each side.
Here're the rear 3 on the right side.
Regards,
Alan
If you're unsure where the exhaust manifold bolts are, it might be wise to have someone help you with this.
Last edited by Alan 71; 09-08-2017 at 01:55 PM.
09-08-2017, 12:18 PM
#14
Le Mans Master
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St. Jude Donor '17, '19
I can feel a puff of air right where the manifold is. I have been told more than once I need to replace the gaskets. a little exhaust comes out after a few minutes. If no gaskets, what could it be?
This is what I bought. It has 1980 in the description.
http://www.parts123.com/corvettecent...50e&ukey=36728
Last edited by ~Stingray; 09-08-2017 at 12:24 PM.
09-08-2017, 12:44 PM
#15
Pro
If you can feel a puff of air at the manifold you need to replace, or add as the case may be, gaskets and the set you bought will work fine.
Breaking an exhaust bolt off in the head is not real common, in my experience, but breaking a stud in the bottom of the manifold is which then requires the removal of the manifold to drill the stud out.
Breaking an exhaust bolt off in the head is not real common, in my experience, but breaking a stud in the bottom of the manifold is which then requires the removal of the manifold to drill the stud out.
09-08-2017, 01:26 PM
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09-08-2017, 02:23 PM
#18
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Hi s,
Those parts have a nice description.
If you'd like to use them you may.
If you decide to do this yourself I'd suggest you find your copy of the 80 AIM for your car first.
Regards,
Alan
Those parts have a nice description.
If you'd like to use them you may.
If you decide to do this yourself I'd suggest you find your copy of the 80 AIM for your car first.
Regards,
Alan
09-08-2017, 02:26 PM
#19
Melting Slicks
Now that Alan has shown you where the bolts are have you tightened every one? I had an exhaust leak when I installed my long tube headers and could swear it was from the front but turned up as the driver's side rear. Hard to tell with your head in the engine bay
Nothing wrong with installing gaskets if you want and it solves the problem but in 78 there were no gaskets installed. Matter of fact in the judging manual there is a deduction if you have them.
good luck.
Nothing wrong with installing gaskets if you want and it solves the problem but in 78 there were no gaskets installed. Matter of fact in the judging manual there is a deduction if you have them.
good luck.
09-08-2017, 03:39 PM
#20
Safety Car
i have not seen one of the manifold to head bolts breaking.. but perhaps they do. the overwhelming bolt breaks I have seen are at the pipe/donut/manifold connections where the 3 studs are.
if you hear the tick tick tick of exhaust and feel the hot exhaust at the head to manifold flange, then yes, you will need new gaskets or put a gasket on them even though there are none.
if you hear the tick tick tick of exhaust and feel the hot exhaust at the head to manifold flange, then yes, you will need new gaskets or put a gasket on them even though there are none.