Extremely Hot Exhaust Hose

wasserhund · Post by **wasserhund** » Mon Aug 06, 2007 9:26 pm

Can someone give me advise.
The wet exhaust hose on the left bank of my starboard motor (GM 350) is extremley hot, much hotter than the right side and the other motor.
So hot the metal coil is starting to show through the rubber. I have checked the water flow starting from the thermostat housing to the hose that feeds the exhaust manifold and removed the manifold and riser to check for blockage. There was some rust but not bad enough to block the water flow. I looked for blockage in the 3" hose itself. I compared the water flow of both motors at the exhaust outlet and they have the same rate. I don't understand how the right exhaust is ok but the left side is overheating. If the water pump was bad the right side should overheat as well.
thanks in advance.
WH

Stripermann2 · Post by **Stripermann2** » Tue Aug 07, 2007 8:38 am

You have a restriction on that side. Most likely riser or manifold.

If they are old and suspect, replace them. I have gone round and round on this issue on my boat in the past and replacement was the only fix. Good luck.

wasserhund · Post by **wasserhund** » Tue Aug 07, 2007 11:22 am

Thnanks Stripermann2, I have done that, the heat is not as bad but still too hot. The heat started to delaminate the inside of the new exhaust hose.

briansselectautos · Post by **briansselectautos** » Tue Aug 07, 2007 7:04 pm

is the engine skipping? or running very rich, that could put raw fuel into the exhaust where it ignites and burns... just a thought.

wasserhund · Post by **wasserhund** » Tue Aug 07, 2007 8:55 pm

Not skipping but it is running rich. It smokes at idle speed and the plugs have signs of a rich running motor. Thanks I think you solved my problem.