Antifreeze oops

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MurrayM

Guru
Joined
Jul 22, 2012
Messages
5,946
Location
Canada
Vessel Name
Badger
Vessel Make
30' Sundowner Tug
So, I drained 6 litres of anti-freeze from the three draincocks on our Yanmar 4JH2-UTE, filled it back up with about 5 litres, started the engine with the fill cap off, and waited. Ran engine at about 1000 rpm for half an hour, and while the coolant did begin to circulate, the level never did drop so I could add the rest.

#1) Is the thermostat toast, or 0C ambient outside temperature too cold and engine just not heating up enough,

#2) will I have to run the boat around for a while under load to get the temperature up (was storming yesterday),

#3) what damage could be done if that last litre doesn't get into the engine for another day or so?
 
Is your hot water heater in the loop?
 
I'm not familiar with the Yanmar but I believe you have an airlock somewhere in the system. You need to "burp" the system. Try briefly opening each of the 3 drain-cocks to see if air/coolant comes out. Post your question on BoatDiesel.com?
 
Is your hot water heater in the loop?

Ahhh...we might have a winner here.

I did shut off the lines to and from the heater for the pilothouse, but I forgot about the line to the hot water tank. It's still pretty much all new to me so I can't remember where the hot water line takes off from. Will check after work.

Thanks.
 
Ahhh...we might have a winner here.

I did shut off the lines to and from the heater for the pilothouse, but I forgot about the line to the hot water tank. It's still pretty much all new to me so I can't remember where the hot water line takes off from. Will check after work.

Thanks.

paypal account now accepting small, unsolicited deposits...:D:D:D
 
paypal account now accepting small, unsolicited deposits...:D:D:D

Sorry, but Larry's the closest to getting paid so far.

Squeezed in enough time to zip out to the boat, and the hot water tank hoses are above the shut offs to the pilothouse heater. (They were closed when I drained the engine).

Larry logically suggested to open petcocks to see if any coolant came out. The starboard petcock didn't, which drains the cylinder head and cylinder body.

But...(insert D'oh! here)...I just realized I didn't open the coolant filling cap when I opened the petcock, so guess I'll be heading back to the boat after work to narrow down the diagnosis.

Life at the bottom of the learning curve :blush:
 
But...(insert D'oh! here)...I just realized I didn't open the coolant filling cap when I opened the petcock, so guess I'll be heading back to the boat after work to narrow down the diagnosis.

Life at the bottom of the learning curve :blush:

For those of you that lost sleep last night wondering...took fill cap off, opened lowest petcock, and out it came :)
 
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