Swollen cooling hose 3.0 OMC Cobra

[swollen]

I have a 1996 Four Winns with a 3.0 OMC Cobra. When the engine is revved up the U-shaped hose between the engine water pump and the thermostat housing swells up. I recently blew one of these hoses that was not very old. Any ideas???? I have disconnected the exhaust manifold, changed the thermostat, and checked the water pump. Now I am stumped.

Any help would be appreciated. Thanks

 

[bruceb58]

Re: Swollen cooling hose 3.0 OMC Cobra

Have you checked how much water is being discharged to the manifold? You might have some blockage in the manifold itself or the opening which feeds the manifold.

 

[swollen]

Re: Swollen cooling hose 3.0 OMC Cobra

Yes I disconnected the hose to the manifold and let it run free. The hose still swelled up.

 

[bruceb58]

Re: Swollen cooling hose 3.0 OMC Cobra

Did you check the opening which feeds the hose going to the manifold? You likely have a blockage somehere. Take off the thermostat housing and check that the passages in the housing are clear.

 

[a70eliminator]

Re: Swollen cooling hose 3.0 OMC Cobra

Like Bruce says, check the passages. Sounds like the bypass passage is restricted, rust can build up at the hose connections nipples making a thumb sized hole the size of a pencil. When the thermostat is closed the water has to bypass, the engine circulating pump just keeps on pumping, even more when revving the motor.