couple of 4.3L engine swap questions. late 90's & 2000

[tazzerblue]

Ok, I'm swapping engines, bought a 2000 Glastron GS185 with bad motor. I have late 90's 4.3L just rebuilt.
This has turned into long process, replacing bellows, gimble bearing, seals, shutters, shift cable, ect. The original 4.3 had the batwing exhaust. Which sounds like a poor idea, from these forums. My replacement had the standard, but with 3" risers. are the 3" risers necessary? It maybe won't fit, measuring I had about 1" clearance, and to wiggle it in is a big question. How do you determine if they are necessary? There are also 2 different gaskets in the risers, one is full flow the other restricted, one is steel? other multi-layer. If I remove riser I assume I install only the restricted one? 2. what is the black sensor that's supposed to be attached to the hull under the engine? Will JB. reattach this? Thanks.

 

[sandkicker]

Elbow = exhaust manifold to drive
Riser = between manifold and elbow to increase height of the top of the elbow per installation issues.
All engines have elbows.... only some have risers.

Gaskets used.... depends on if engine has heat exchanger or not.

 

[makomark]

the need for a riser is if the installation does NOT provide enough height above the waterline for the exhaust elbow...

Most MCM installs don't need them.

As Bob said, the gaskets needed depend on the configuration of the parts used and the cooling system design.

 

[Fun Times]

The black sensor appears to be a transducer for a depth gauge often adhesived down to the bottom of the bilge area.