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| | | Joined: Aug 2008 Posts: 116 Shop Shark | | Shop Shark Joined: Aug 2008 Posts: 116 | I just bought a 1.5 ton '55.1 Chevy and the 235/261 exhaust pipe flange is leaking. I seem to recall that they take a flat gasket as well as a doughnut. Is the doughnut special...like smaller than a modern one? It seems to measure 1-15/16, but the rest of the pipe is 1-7/8. Does anyone know for sure the size on these things?
Thanks,
Jim | | | | | Joined: Aug 2005 Posts: 1,186 Shop Shark | | Shop Shark Joined: Aug 2005 Posts: 1,186 | If you have the remants of the original, just take it to your local FLAPS.
Bruce | | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 |
My 1959/60 261s have a flat gasket - no doughnut.
My 1954 235s use a doughnut - no flat gasket.
| | | | | Joined: Jan 2008 Posts: 4,961 'Bolter | | 'Bolter Joined: Jan 2008 Posts: 4,961 | Doughnuts work good on Ford Y-Blocks, but are not needed on Chev. | | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 |
If it is a 54/55-1st exhaust manifold, I'd bet it used a doughnut (unless 54/55-1st H-D Chevy trucks used a different manifold from the lighter trucks).
I have, however, sometimes been successful using a later flat-gasket with a "doughnut" manifold and a flat-mating-surface (later style) exhaust pipe.
| | | | | Joined: Nov 2006 Posts: 2,544 Shop Shark | | Shop Shark Joined: Nov 2006 Posts: 2,544 | We have a '40, '49, '50' '51 and '53. They all have a donut. | | | | | Joined: Aug 2008 Posts: 116 Shop Shark | | Shop Shark Joined: Aug 2008 Posts: 116 | Thanks for the response guys. Here's what I did. When I took it apart, there was a 7/16" long portion of exhaust pipe that extends into the exhaust manifold casting. It was all rusted out though, so I welded a new piece onto my flange just like new. I straightened the flange really good and it worked like a charm. The fillet formed from welding fit right into the casting's chamfered hole and the gasket just closed up everything tight as a jug. | | |
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