SailNet Community banner

1 - 4 of 4 Posts

·
Registered
Joined
·
57 Posts
Discussion Starter #1
I have drained the coolant in the fresh water system our Yanmar 3gm30f.

I supplied new coolant by filing up to the mouth of filler port on the heat exchanger and to the minimum level of the subtank.


After the supply of new coolant I ran the engine in idle for about 30 minutes.

When opening the fillercap on the heat exchanger I noticed that the coolant level had decreased whereas the level in the subtank had increased to between minimum and maximum.

I recall that the level in the subtank was at the minimum mark and the level in the heat exchanger up to the mouth of the filler cap before I drained and supplied the system with new coolant.

So I am wondering if something is wrong now
 

·
Senior Smart Aleck
Joined
·
2,152 Posts
No, just put more coolant in the filler port on the heat exchanger until it is as full as the manual directs, probably up to the exit hose that drains to the overflow tank. Reads as if your system operated properly and the extra coolant, when hot and under greater pressure, flowed into the overflow tank as it should.

Just make sure your overflow tank is at the proper level with respect to the filler port exit hose.

If your coolant level in the heat exchanger is proper, and then your overflow exceeds maximum you might have a problem of too much coolant in the system.
 

·
Registered
Joined
·
57 Posts
Discussion Starter #3
The problem seems to be that coolant will not flow back from the subtank to the heat exchanger when the engine is cold.

Is it likely that the missing flowback is due to air in the hoses to the water heater ?

And if yes how do I bleed the system for air ?
 

·
Registered
Joined
·
57 Posts
Discussion Starter #4
Problem has solved. When the engine was allowed to cool for a night coolant was sucked from the subtank to the top of the mouth of the heat exchanger.

Thank you for your help
 
1 - 4 of 4 Posts
Top