I agree 100%. That is also why I always say to keep it stock and forget a crossover when someone ask for opinions. Water pressure, temps, and condensation issues, just ain't worth it. I'd guess Mercury has more research in this than anyone else. IMO

OK boys, your turn! :)

True, but how many of die gracefully vs how many of them suffer a catastrophic failure, taking out the belt that drives the raw water pump?

You can run a crossover with a thermostat and eliminate another source of breakdowns. IMHO, one less thing to break is always a good thing.

Scott B

If I wanted to float around powerless, I'd get a blowboat :eek:

Great Thread Guys,
I did install crossovers with T-stats in a 28' Cigarette that we had. They worked well to create more room to work on the front of those engines. Man they were stuffed in there...

Scott , better check your figures again.
I've been there and done that and it worked.:p
It was good at idle and I could beat on it all day with no problem. If I ran just off plane , you know , bow in the air pushing water...It would run up to 200*

And I have run a boat (OB) with no impeller whatsoever. However, I prefer not to do it.

IMO, the circ pump is dead weight, and when it blows a bearing you cannot pump against it since your raw water pump is now dead also... I should have clarified that in the first post :) :)

I dont see the point of a circ pump when we all know it is a problem child, so why have it if it is not needed?

Scott B

If I wanted to float around powerless, I'd get a blowboat ;)

Or get twins;)

:D :D :D


Scott B

Scott, I hear ya. I'm going on the fact that in my 35yrs of boating,(I'm 40 :) ) I have never had nor been a witness to a pump going out. It has only been on this board in the last 3 yrs that I have heard of guys having trouble with pumps. And I'm on the water every weekend during the summer. So to me, it is not worth the hassles.

I don't understand your thought here:
IMO, the circ pump is dead weight, and when it blows a bearing you cannot pump against it since your raw water pump is now dead also...

They are driven from separate belts. The water pump will push water past a non rotating circulating pump because the impellor is in a void with no direct sealing. Thats why you can spin it by hand easily with the motor full of water as compared to your raw water pump.

Boat On! :)

True.. [I really need to learn to clarify things better..] I am primarily thinking of serpentine belt accessory drive setups. You are correct in the older boats having separate belts. Considering mine are older boats you think I might remember that wouldn't' ya... :eek:



Scott B

Back to the twins are better.. Or, are we still discussing boats? :D

As to the 20-40hp BS, how much horsepower could you possibly put through a fractional hp vee belt?