Exhaust Gasket Rebuild

On my way south from Mexico it became evident that the gaskets between the exhaust pipe flanges were leaking.  Soot was leaking through the heat blankets and there was more heat than normal going up the stack.  So in Nicaragua I took the exhaust pipes apart and installed new gaskets.  In 2009, Tom Mackey on his Nordhavn 46 Lucent also replaced some of these gaskets and found that the flex pipe had a crack.  His photos are also included below.

M/V Jenny 46-39

Once the heat blanket was removed, I could see cracks in the gasket.

Once the pipes were apart, it was apparent that the gasket had disintegrated.  I had to be careful not to knock pieces into the exhaust pipe.

I ordered some premade gaskets and gasket material from Hatton Marine (www.hattonmarine.com) since I did not have the measurements yet and could only guess.  I used the material to cut my own gaskets for this piece. The gasket material is 1/8" thick and withstands temps up to 1200 degrees. A 12"x12" sheet costs $15.50 plus shipping.

Here are the measurements for this coupling.

Here are the homemade gaskets.

And, these are the premade ones.


M/V Lucent 46-08

Tom Mackey found a better source for the gaskets, but had a slightly different problem.  He purchased both gasket sizes in 1/8 and 1/16 inch thickness. They are specked at 1000 degrees F and were only a few dollars each. The minimum order was $50 so I bought $50 worth. Consequently, he have extras that he does not need and would gladly send them to others that need to do the exhaust task. He also have the information on the sealant. It will take 1200 degrees F.  He also purchased some ceramic blanket material to wrap the flex section and elbows. It's rated at 2000 degrees F.  Tom can be reached at TMackey2@cfl.rr.com

The gaskets were purchased from www.allstategasket.com 

The sealant came from www.DeaconIndustries.com  

Ceramic blanket came from Bailey Pottery Equipment Corp. Kingston NY

The flex coupling unwrapped.

This shows the cracked flex coupling which caused some of the blackening of the insulation. The remainder was caused by a leaky top flex section gasket.

The gaskets and sealant.

A gasket installed.

The flex coupling re-installed.


Wrapped with the new blanket material.

The flanges wrapped with the new blanket material.

Old blanket wrapped around the flanges.

The wrap painted with engine paint.