Murcury 60 EFI 4 stroke water presure and overheat problem

[Edward55]

Pressure rises to about 15 psi when 1st started and cold engine then drops to about 4 psi and never rises again. On the bay at wot or 6000 rpm, overheat alarm sounds after 5 minutes and low water pressure. Tale-tale sprays fine and water is very warm. Alarm goes of when throttled back below 4000 rpm. Water pump replaced and thermostat removed. Any suggestions or ideas? Maybe poppet valve or clogged jackets? Tale-tale good pressure.

 

[schematic]

Re: Murcury 60 EFI 4 stroke water presure and overheat problem

Was the complete water pump replaced or just the impellar?
was the old impellar burnt?
Was the old impellar missing any paddles?

Definitely would also check poppet valve

 

[Edward55]

Re: Murcury 60 EFI 4 stroke water presure and overheat problem

Thanks Chief for responding. Only the impellar was replaced and the one removed showed very little wear and nothing broken. The stainless cover showed no scratches or wear. The tale-tale sprays normal pressure. Only the pressure gage shows loss of pressure after the engine warms up. Is there a way to check the poppet? The poppet is the only other thing (other than thermostat) the I can think of that controls the water flow.

 

[MARV1]

Re: Murcury 60 EFI 4 stroke water presure and overheat problem

Impeller in correct direction? Motor up too high out of transom? Check for clogged intake or one of water fittings clogged up...

 

[Edward55]

Re: Murcury 60 EFI 4 stroke water presure and overheat problem

Thanks Cadet. I have already questioned and rechecked the direction of the impellar. The pressure drops with lower unit in bay, or drum, and even with the mickey ears. How can I check for clogged intake or water fittings? The tale-tale sprays good pressure even after the pressure gage drops.

 

[schematic]

Re: Murcury 60 EFI 4 stroke water presure and overheat problem

find poppet valve and inspect for sticking open. Look on parts break down to find it if you don't know where it is....

 

[Timestep]

Re: Murcury 60 EFI 4 stroke water presure and overheat problem

Sounds like the water grommet is closing up, a common problem, see http://forums.iboats.com/mercury-mariner-outboards/removing-60-efi-adaptor-plate-removal-520989.html

There is no poppet valve in this engine.

Dave