Yanmar 3ym30 coolant question

[Mike Oatsvall]

I noticed that the overflow tank at the back of the engine was empty. So, I removed the top from the, I guess it's the heat exchanger tank, to see how low it was and red coolant spilled onto the engine. Topping it off from there is not the answer.
Is there some secret to adding coolant? Should I add coolant to the overflow container?
And then there is the question of what kind of coolant. Are most folks using Yanmar YG30 UltraLife?
Thanks,
mike

 

[Steve Dion]

Mike: I don't know exactly which coolant your boat has, but they (Hunter) are only recommending the Extended Life (orange) coolant. If you have not changed the coolant you may want to contact the dealer and ask them what was in there. Our Yanmar guy is using the Shell 50/50 blend (no water required).

 

[Ken13559]

My Yanmar 2GM20F came with Green coolant (original from Hunter factory). I later changed it to Shell Orange colored Extended/Long Life. If you're topping up, make the HE is top up, then fill up the overflow tank to just over the low level. that will do. If you need to change coolant type, I understand you need to thoroughly flush out the old one (red or green) before adding the new one (orange colour). I did flush mine system thoroughly with fresh water and finish off with flushing some orange coolant through and drain before topping up HE and Overflow tank.