Exhaust manifild to pipe gasket?
#1
08-11-2020, 04:02 PM
Exhaust manifold to pipe gasket? 78 K5 350
Exhaust pipe to manifold driver side. Is there a gasket or seal? It was just fit pipe to manifold and the manifold flange is a bit missing in spots and it leaks.
PS the trick to getting the heat riser block off the passenger side manifold is to tap on it at the front side with a little tack hammer. That bounces the riser side to side and knocks the rust out. Prying down on one side just breaks screwdrivers...
PS the trick to getting the heat riser block off the passenger side manifold is to tap on it at the front side with a little tack hammer. That bounces the riser side to side and knocks the rust out. Prying down on one side just breaks screwdrivers...
Last edited by daveca; 08-13-2020 at 08:39 AM.
#4
08-11-2020, 05:24 PM
I'm wondering if you go with a light sand to even it out? Should be able to tell by feel... maybe lol...
I'm thinking I got the same problem, got a hiss from the side I havent found yet, but havent looked either lol...
I'm thinking I got the same problem, got a hiss from the side I havent found yet, but havent looked either lol...
#8
08-12-2020, 01:21 PM
1978 K5 350. It was fit together without a gasket or seal,and parts houses font list a seal or gasket.
Id made a gasket of asbestos material for the heat riser but the gasses eroded it away so plain material wont work. It must have steel to resist the hot gasses.
The passenger side has a donut but nothing on the Driver side and the chronic gas leaks have eroded the material on the manifold.
Going to try fitting a donut in but dont think it will last. The donut only has the correct profile on one face. The donut is both sides convex, but the manifold is convex and pipe is concave so the donut wont fit against the manifold properly.
Its a 2 inch pipe and donut ID and thats a little smaller than the size of smaller food cans...theyre stainless steel. May have to make a seal.
Id made a gasket of asbestos material for the heat riser but the gasses eroded it away so plain material wont work. It must have steel to resist the hot gasses.
The passenger side has a donut but nothing on the Driver side and the chronic gas leaks have eroded the material on the manifold.
Going to try fitting a donut in but dont think it will last. The donut only has the correct profile on one face. The donut is both sides convex, but the manifold is convex and pipe is concave so the donut wont fit against the manifold properly.
Its a 2 inch pipe and donut ID and thats a little smaller than the size of smaller food cans...theyre stainless steel. May have to make a seal.
Last edited by daveca; 08-12-2020 at 01:26 PM.
#9
08-12-2020, 04:48 PM
Got it!!!!!!!
Cut a 2 inch hole in the center of the bottom of a Campbell's mushroom soup can. Cut the bottom of the can off, about 5/8 inch up. Sheet metal shears were used to cut it. Be careful THE CUT EDGES ARE SHARP.
Put the bottom piece of the can in right side up in the flare on the exhaust pipe, centered on the manifold and tightened the 3 nuts..
WORKS PERFECTLY. Its so quiet I can hear the gear whine in the tranny.
Don't know if it will last but it didnt cost much and is easy to replace. And now there's a yummy green bean casserole to boot!
The heat riser gasket and donut for the passenger side were NAPA 9672 F7135 Fel Pro Exhaust flange ( heat riser to manifold) and 31 400 exhaust gasket ( the donut). Be careful with the donut, its very soft. Make sure its centered before tightening the flange.
Avoid using copper or aluminum in contact with hot exhaust gasses. They compress nicely but melt at 1100-1300 F and fire out the exhaust will melt the material.
Tried sanding the cast iron. Failed, the iron is too hard. Was able to sand the carbon and rust deposits off the manifold and exhaust pipes which helped.
Tried to elimnate the useless heat riser block. The manifold has a depression that fits the donut gasket but the exhaust pipe is cut and formed to fit with the heat riser and wouldn't fit without it. It would work with a new down pipe from the manifold.
Put the bottom piece of the can in right side up in the flare on the exhaust pipe, centered on the manifold and tightened the 3 nuts..
WORKS PERFECTLY. Its so quiet I can hear the gear whine in the tranny.
Don't know if it will last but it didnt cost much and is easy to replace. And now there's a yummy green bean casserole to boot!
The heat riser gasket and donut for the passenger side were NAPA 9672 F7135 Fel Pro Exhaust flange ( heat riser to manifold) and 31 400 exhaust gasket ( the donut). Be careful with the donut, its very soft. Make sure its centered before tightening the flange.
Avoid using copper or aluminum in contact with hot exhaust gasses. They compress nicely but melt at 1100-1300 F and fire out the exhaust will melt the material.
Tried sanding the cast iron. Failed, the iron is too hard. Was able to sand the carbon and rust deposits off the manifold and exhaust pipes which helped.
Tried to elimnate the useless heat riser block. The manifold has a depression that fits the donut gasket but the exhaust pipe is cut and formed to fit with the heat riser and wouldn't fit without it. It would work with a new down pipe from the manifold.
Last edited by daveca; 08-12-2020 at 04:57 PM.
