Cooling issue/Impeller Replacement

[gcope63]

I took the boat out this weekend (third trip of the season) and immediatly started having overheat issues after leaving the dock. I haven't had a chance to tear into it but am suspecting I have a bad or broken impeller in the water pump. I have ordered a new impeller since even if it isn't the issue its 7 years old and should be replaced. My question is, is if I remove the 3 screws on the pump will the cover just pull off? Do I need a puller to remove the impeller? Is there anything I need to watch out for when I put it together? My motor is a 2001 VP 5.0Gi.
If it isn't the impeller what other possibilities?

Thanks

Gary

 

[Don S]

Re: Cooling issue/Impeller Replacement

I think you will find you have a 2000 model engine, 2001 didn't have a 5.0Gi. If you have your full model number or SN we could find out for sure what year it is. But, it's still the same raw water pump.
There should be 4 small screws holding the cover to pulley. There is a screw between the hoses.
You probably need an impeller, and if the vanes are gone, you will need to find them as they will cause an overheat too.

 

[Maclin]

Re: Cooling issue/Impeller Replacement

With the cover off you should be able to coax it out with two screwdrivers, one on each side prying gently....

 

[gcope63]

Re: Cooling issue/Impeller Replacement

Don,
Your right, for some reason the boat is a 2001 but the model of the motor shows it as a 2000 (5.0 Gi PEFS). My suspicion was the same, I figured a blade came off and lodged somewhere. Is there a flow diagram somewhere available to see where an blade might go after leaving the pump area?

Maclin,
Thanks for the help, I was hoping it was something easier to remove..

Thanks

Gary

 

[Don S]

Re: Cooling issue/Impeller Replacement

Yes, an EF model is a 2000 model. Happens quite often on boats. Boat years start on Jan 1 of that year. Motors are somewhere else.
Those impellers normally come off still "IN" the cover. A pair of needle nose pliars pulls them out easily.

 

[gcope63]

Re: Cooling issue/Impeller Replacement

Don,
WOW, great diagram! I suspect that the vane may be plugging the output of the pump since we disconnected the hose at the output of the pump and got nothing out when we started it.
Thanks again for the information!!

Gary

 

[gcope63]

Re: Cooling issue/Impeller Replacement

Don,
If the impeller is okay can I use a hose and backflush the input line to the pump? I may have sucked up some vegetation on my last trip out..

Thanks

Gary

 

[Don S]

Re: Cooling issue/Impeller Replacement

Sure you can, you could also pull the outdrive and try the backflush without going thru all the sections of the drive.
PS. here is something you may find handy if you don't find the problem.

Volvo Penta Overheat Diagnosis

 

[gcope63]

Re: Cooling issue/Impeller Replacement

Very cool Don! Thanks for the information! I am going to pull the raw water pump cover tonight and see what the impeller looks like...

Gary

 

[gcope63]

Re: Cooling issue/Impeller Replacement

Pulled the cover last night and all that was left was a hub! Everything else was black rubber sludge! Found a couple of pieces of blade in the output but nothing else. Planning on flushing it out next week. I guess when it went it went!

Gary