Dusty Times

Does Merc make a better impeller and housing than say Quicksilver?

Any suggestions on getting rubber chunks out of a 500 EFI? Changed the impeller and it still runs a little warm. Since the impeller exploded and it was fine before. Could these chunks make it to the thermostat?

marinetrans

Merc's 540 Bulldog went back to the 2 piece housing w/ wear plates. The impeller and housing seem to last longer. Both housings are plastic. Back to using 3 gaskets. Chunks may be in input side of engine oil cooler.

mcollinstn

Find the hose that goes from the cooler(s) to the water neck. Disconnect it from the waterneck. Clamp it to a garden hose. Remove is from the raw pump.

Back flush it with full hose pressure. Chunks will fly out of it.

You're finished.

(do this at every impeller service)

Dusty Times

Thanks,
Just found a waterflow diagram. Sounds like that will work.
Will this work well also with the sand clogs low water pickups are famous for?

mcollinstn

No, you can fill your engine blocks with sand.

And that really sucks.

Bill272

Whenever you change an impeller, count the number of pieces you take out. That way you'll know if you have any more stuck futher down in the system.

Dusty Times

I thought that would be an extra security measure until the pieces were to small to put the puzzle back together.
This was on the beach. Hanging upside down in the engine compartment.

force 320

has any one here used the blue impeller by Globe Rubber Works, they claim you can run dry 15 min?

FlyFast

I have a blue from globe. It works good for me but my setup is not stock. I run full closed cooling with a bravo water pump. My cooling system starts to build pressure over 4200 rpm. Under 4200 rpm my cooling system will run at 10 psi or less. I have heard that the pressure might be a little less with the globe. I have lots of water and good cooling. I noticed no difference between it and the stock merc bravo impeller. I have not run it dry yet. I have smoked the stock ones on the hose. So far so good with the blue.

97BossHammer

Dusty Times - can you post that wire diagram, or where you got it from? I need one also, missing some chunks also.