lack of coolant

[PMF1984]

Ski,
This would occur when underway, would that apply?
John

 

[Ski in NC]

No, only a problem with cold storage.

 

[DavidM]

Rather than speculating where your coolant could be going, why don't you pressure test the system.

Check with your local auto parts store. They often rent or loan cooling testing kits to their customers. Pressurize the system using one of their adapters at the filler neck. Then look for leaks. Wipe each hose connection with a paper towel and look for coolant. You can even dye the coolant to make it show up in black light.

If you can't find a leak, then watch the gauge and see if it drops over an hour. Any pressure drop is an indication of a leak so keep looking. The leak may be in the main heat exchanger or lube oil cooler if it is coolant cooled. Or it could be a head gasket. Check for the later by looking for bubbles in the overflow reservoir while under load.

But my guess is that this small leak is at a hose connection and you will quickly find it if you pressure test.

David

 

[Comodave]

I bought a pressure test kit for about $80 off Amazon. Found my leak in a couple of minutes. Cheaper than hiring a mechanic for sure.

 

[PMF1984]

Just as an update on my coolant loss. I operated under the theory that perhaps it was just the tank cap that was the problem, so I got two replacement caps from Westerbeke. These both leaked when the boat was at rest.

I noticed that my expansion thank had a crack under the mounting wire and theorized that when the engine was hot the coolant expanded and leaked out the crack. Got a new tank.

Still had a problem.

Checking on something else, I noticed a small sputtering (I was underway at the time) at a mounting bolt for the fresh water pump which is mounted on the engine. I know that the Palmer Dodge engine head bolts pierced the water jacket and you had to put sealant on the head bolts. Do I have the same situation here? If so what is the proper sealant?

Thanks for suggestions so far.

John

 

[kchace]

Checking on something else, I noticed a small sputtering (I was underway at the time) at a mounting bolt for the fresh water pump which is mounted on the engine. I know that the Palmer Dodge engine head bolts pierced the water jacket and you had to put sealant on the head bolts. Do I have the same situation here? If so what is the proper sealant?

Thanks for suggestions so far.

John

If its just the bolt threads and not a crack.... The old standby for bolts that penetrated the water jacket was Permatex #2. That would certainly work but there are probably better things these days - something like Permatex Ultra Black.


Ken

 

[PMF1984]

I tried some red gasket maker around the bolt just under the head. The bolt was not tight. Water pump replacement last year seems to have been done with the old lock washers.[emoji32][emoji32]