I need to pull my motors for some other work and was wondering if the closed cooling system off of a HP525 would fit on a HP500EFI.

When the boat goes back into the water, I will be boating in salt and thought maybe it would be a good time to change the system.

Anyone done this before?

-Phil

I wondered the same thing, and was actually quite suprised when I realized that the 500EFI's weren't closed loop, any idea why? Other than [of course] cost savings?

Michael

Back then none of them were, 525sc, older 600 or 575, etc.

I know it adds a little weight, but how much could it be?

A full system runs around $750.00

Is that a new 525 system or one that you have put together?

not with 525efi parts...but it is easy to do with other kits...

We have done systems for the 502EFI, HP500 502MAG. Ours is not a Merc 525 system but the Heat Exchanger is made by the same people that builds them for Merc.

500EFI has iron heads - 525 has aluminum - closed loop is to keep the salt water from reducing the engine to rust.

Yea I know but I would like to keep the salt water out of the fuel and oil coolers as well as the iron block and heads. Seems that it would help all around.

What do others think?

if i were in salt water that would be the only way i would go..