4.3L Has Hot Riser on Port Side

[Gaetan Carrier]

Just installed factory exhaust manifold on port side to get dry-joint back to original setup, previous owner had installed after market manifold and it was leaking. The riser looked ok so re-installed with new manifold. Removed hoses leading to risers while engine was at idle and same amount of water (not much) seems to be going to each riser but haven't checked hoses leading to manifolds.

The port side is much warmer and really can't leave your hand on it too long. The temperature gauge seems to run 160-175 degrees. The engine was already running hot before the new manifold. I believe the gaskets were installed correctly with the restrictor tab going between spacer and riser, in the front by the inlet hose.

Outdrive impeller may need replacing but one side of engine seems fine. Wondering if I have clogged passages in the block/head or obstructions in the riser or exhaust?

The engine is a 2004 vintage with original everything except the new manifold.

 

[191Seanymphstriper]

Re: 4.3L Has Hot Riser on Port Side

Most likly its a bad riser very common! Even if it looks clean double check to make sure the right gaskets are on the riser. Start There/ Also when removing the casket do a good inspection. Thats where you may find the problom under that gasket. Most likly. You meed a riser

 

[jerryjerry05]

Re: 4.3L Has Hot Riser on Port Side

It's only 6 years old and the manifold/risers should last way longer than that.
Replace the impeller.Then put it in the water to run it.
Running it on the hose probably isin't suppling enough water to keep it cool.
Check the thermostat for blockage.J

 

[191Seanymphstriper]

Re: 4.3L Has Hot Riser on Port Side

If your running it in salt 6 years is a long time. Frshwater 7 8 years max. Yes check the thermastat and change it its cheap enough. But I bet you its the riser with built up salt if running in salt!

 

[Gaetan Carrier]

Re: 4.3L Has Hot Riser on Port Side

Changed the impeller, it had some small grooves and the SS cup also had some small grooves that I cleaned up with an emery cloth (reminder to everyone to note direction of impeller vanes before removing). Overall cooling for both risers was much better and I ran hard all afternoon with equal temperatures for both riser.

When I came back to dock through the long no wake zone, the port side riser got much hotter again. Probably will have to break down and replace riser but sure doesn't seem to have much scale.