Exhaust manifolds and risers for 2001 Maxum 2100 SR

[fellwood]

Does anyone know how I can find the size of the exhaust manifolds and risers for my 2001 Maxum 2100 SR bowrider? I have a 5.0 Mercruiser engine. I'm thinking about installing them myself, or having a friend install them. Thanks so much, Frank

[mmwjr]

Frank welcome aboard.

GM 5.0 and 5.7 small block mercruisers all use the same manifold with center port and for your year the 4 inch riser. This is probably the most common engine exhaust out there so very easy to find.

Good luck and let us know how it goes.

[shrew]

They are easy to install. I had a friend show my a trick to maintain the gasket alignment. He removes the exhaust manifold and gasket. Then cuts the heads of the old bolts. inserts the old headless bolts and turns them a few turns so the threads can grab. Slides on the new gasket over the old headless bolts, then slides on the new exhaust manifold. Then unscrews one old bolt and replaces with a new bolt until the new head-on bolts are all finger tight. Then goes around and torques them all down.

The old headless bolts essentially act as guides for the gasket and manifold.

I'd also suggest genuine Mercruiser parts on this job. 3rd party are not as good.

[fellwood]

Thanks so much for the gasket tip. How did your friend cut the heads of the old bolts? Also, when you replaced your exhaust manifolds, did you replace the risers also?

Originally Posted by shrew

They are easy to install. I had a friend show my a trick to maintain the gasket alignment. He removes the exhaust manifold and gasket. Then cuts the heads of the old bolts. inserts the old headless bolts and turns them a few turns so the threads can grab. Slides on the new gasket over the old headless bolts, then slides on the new exhaust manifold. Then unscrews one old bolt and replaces with a new bolt until the new head-on bolts are all finger tight. Then goes around and torques them all down.

The old headless bolts essentially act as guides for the gasket and manifold.

I'd also suggest genuine Mercruiser parts on this job. 3rd party are not as good.

[mmwjr]

Risers typically wear out before the manifolds so yes replace them.

Instead of cuts bolts get a piece of all-thread and insert 2 6 inch pieces into the 2 ends then install the gaskets and manifolds plus the center 2 bolts. Remove all-thread and install bolts. Torque all bolts then install the riser.

[Intern8tion9l]

All good tips here. These guys gave me solid advice when I just took on this project for myself a couple months ago. Went great and it was my first time

[Kevlar7r]

An alternative for the exhaust gasket, I bought automotive exhaust gaskets, part number MRG 150A. They are hooked on the ends, so I started the 2 outside bolts, and dropped the gasket in.



Having just recently done exhaust, go2marine.com was the best price I could find.

[fellwood]

Hi Mike,

Thanks so much. This was very helpful. I'll let you know how it go's. Frank