Fresh water cooling system

[elcojo2]

To whom it may concern,

We just bought a catalina 28 with an M320 universal diesel engine. As I am getting familiar with the boat. I was looking at the fresh cooling system and notice if I try to remove the coolant cap it starts pouring out coolant. Previously owned boat had a universal 5411 so I am not really familiar with what is normal and what is not. Engine seem to be running OK. Now I read that this could mean an overpressure system, bad cap or something way worse. I would appreciate any idea where to go from here.

Thanks in advance for the help.

 

[TimFromLI]

I assume that is when the system is cold. Does it have an overflow reservoir?

 

[NYSail]

Is the overflow tank above the cap? If so that’s where the coolant is coming from. I have to open mine and remove the feed line or it syphons back and over flows.

 

[elcojo2]

Correct is when the system is cold and yes does have the recovery tank above the cap in one of the storage compartments in the cookpit. I assumed this is why I get coolant probably. So I should remove the line so I don't get the coolant from the recovery tank coming down. This is normal then. After that I can open I check. If the coolant needs to be replace how often and do I drain from where? I saw a drain on the coolant reservoir is there somewhere else where I need to drain in order to install fresh coolant?

Thanks again.

 

[TimFromLI]

Generally there is a drain plug on a low point on the engine block for draining coolant also drain the reservoir. Hard to say how often, it depends on the type. I'd say every few years to be sure you don't lose the corrosion protection. refilling can be tricky due to potential air locks in the coolant hoses.

 

[kloudie1]

If the cap is good and there are no coolant leaks around it, then you can check the fluid level in the overflow bottle .. if ya want to check or fill from the cap, remove and quickly plug the overflow line or pinch it gently with pliers to stop coolant from running out of the open cap while you check level. Alternately, install a little ball valve to shut off the overflow line when you waant to open the cap.. My personal preference would be to gently pinch off the line with pliers while using the other hand to open the cap.. do this with the engine COLD.

 

[Hello Below]

Often the overflow bottle/reserve tank will be held in place by a bracket or a couple of screws. Free the tank and temporarily relocate it below the filler cap. The coolant will now drain into the overflow tank allowing you to remove the filler cap with little to no mess.

 

[elcojo2]

Thanks so much for the responses and direct me in the right direction.