Cooling system question

[tacx]

I'm replacing the circulating water pump on my mercruiser 5.7 L that is not a closed system, but a system which gets its water from the outdrive.

So I was just wondering if the pressure in my system, when running, is allot lower than the pressure in a closed cooling system when running? I would think it's allot lower?

 

[Rick Stephens]

Yup, almost nothing. Only pressure is from flow restrictions which are minimal. Means that the cooling water will boil at lower temperatures than a closed pressurized system.

 

[alldodge]

I have open cooling and my pressure is 20 to 25 psi at cruise and 2 to 5 psi at idle with a Bravo drive

 

[Bondo]

I'm replacing the circulating water pump on my mercruiser 5.7 L that is not a closed system, but a system which gets its water from the outdrive.

Ayuh,..... Why, is it leakling,..??

As AD says, the pressure can get quite high,.....

The raw water pumps move Alotta volume, which increases the pressure,....

 

[tacx]

My water circulating pump was leaking from the bearing weep hole. Worn bearing. Replaced pump and alls good.

Just asked the pressure question out of curiosity.