Here's Johnny

Anyone ever add fresh water cooling to a stock Merc 575sci ? I will be pulling both engines this fall to go through them again and I want to convert them to fresh water cooling. Any one ever do this that can give some insight and/ or ideas......?

teamsynergy

I am a bit confused... Are you saying you want to add a closed cooling system to them? Like the 496's come with?

Vinny P

I will be rebuilding Johns engines again. Yes, we want to add closed cooling to these stock 575 SCI's. Similiar to what Merc puts on their 496's and 525's. However, that system will not work on 575's. We are looking into using Monitor Products. The problem will be how to mount the heat exchanger. Since the engines are supercharged, there is no good place to mount the heat exchangers. The only option I can think of, is to mount the exchanger down low on either the stringers or possibly the front engine plate. The next issue would be plumbing it and how to fill the system with coolant. I am thinking I can fill from an adapter mounted to the intake manifold or possibly the type of adapter that can be cut into the hose going to the intake.

Here's Johnny

Thanks Vinny......

smiklos@sunprint

iTrader: (1)

Monitor's stuff works great! The off engine units should work fine. They are a good company not far from where I live. I would call and speak with the engineers there. I did a 540 single and was really happy with the results. They bypass water always through a thermostat on the cooler. the engine I did had really even temps front to back (I did add lines from back of heads to front) I was comfortable running 185F and they oil would get temp (180 in pan before cooler on initial idle 220 after hard run) without a thermostat.
Steve

motor

iTrader: (3)

If you do this .I have a couple coolers that came off 540cid 575 hp na mercs in perfect condition .Fresh water only .Motors were plumbed with antifreeze in exhaust manifolds, raw water in elbows only ...Big coolers

Here's Johnny

Thanks Motor..... If I need them ill let you know....... Have to figure out a few things first......

smiklos@sunprint

iTrader: (1)

How much for coolers? Got any pics?

4bus

iTrader: (4)

What do expect the engines temps to be after the addition of the closed cooling?

Vinny P

I am very confident that the engines will continue to run at the same temps they do now. As long as the heat exchanger can dissipate the proper amount of heat, there will be no problems. Right now, the engines run about 150*.