1969 OMC 120 exhaust manifold upgrade

[verno]

I have a 1969 OMC stringer, it has the old style exhaust manifold with two single barrel carburetors, the manifold and elbow are trash. I have a newer style for single two barrel carburetor to replace it. The newer 70's style configuration leaves quite a gap between the manifold riser outlet and the port on the intermediate housing, about a foot. My question is can I simply install a longer exhaust hose where the old cast iron parts were, about a foot long hose would be necessary and it would have to have a 90 degree turn to it.. Or perhaps someone knows what parts are needed for such a conversion.

 

[Bondo]

Re: 1969 OMC 120 exhaust manifold upgrade

I have a 1969 OMC stringer, it has the old style exhaust manifold with two single barrel carburetors, the manifold and elbow are trash. I have a newer style for single two barrel carburetor to replace it. The newer 70's style configuration leaves quite a gap between the manifold riser outlet and the port on the intermediate housing, about a foot. My question is can I simply install a longer exhaust hose where the old cast iron parts were, about a foot long hose would be necessary and it would have to have a 90 degree turn to it.. Or perhaps someone knows what parts are needed for such a conversion.

Ayuh,.... Exhaust hose will collapse if bent to a 90,.... you'll need an elbow to make that turn,...

 

[verno]

Re: 1969 OMC 120 exhaust manifold upgrade

Ayuh,.... Exhaust hose will collapse if bent to a 90,.... you'll need an elbow to make that turn,...

Thank you for the reply. It turns out it is only 8-1/2" difference. So then it should work fine with a pre-formed 90 degree elbow? Then should I use standard 90 degree pre-formed hose or should I be using an extra high temp 90 degree silicone hose?

 

[bruceb58]

Re: 1969 OMC 120 exhaust manifold upgrade

There was someone on here a while back that had a link to where you could buy exhaust parts to put in between exhaust hoses to make bends like this. I will try to search. You should too.

If I was going to do this, I would probably weld myself up some stainless steel tubes with bends in them.

 

[verno]

Re: 1969 OMC 120 exhaust manifold upgrade

Thank you for the ideas. There are ready made parts available from several sources. Found a metal elbow for a jet ski, and it even had silicone high temp hoses, which fit perfectly.

There was someone on here a while back that had a link to where you could buy exhaust parts to put in between exhaust hoses to make bends like this. I will try to search. You should too.

If I was going to do this, I would probably weld myself up some stainless steel tubes with bends in them.