yanmar 1500 coolant

[Coyote]

Anyone know the capacity of the cooling system on a 1500 so I can get the 30% AF right? Thanks

 

[tonyw]

Coyote, I'm not sure about the capacity, but I normally pre-mix my anti-freeze/coolant at 30-40% and then add it to the radiator.
I don't know about the 1500, but if it doesn't have a water pump, it's best to be sure the mix is right when it's added.

Tony

 

[DetroitMike]

Coyote,

I have a 1500 also and can't tell you the capacity, but I just mixed up a bunch at the 30% to 40% and filled it up. It's never given me any trouble at all.

And Tony is right. The 1500 does not have a water pump so the correct mix ratio of the coolent is very important. With that ratio right, you should be good to go. One other thing, when I got mine it did not have and overflow bottle. I bought one and it works very well. Make sure you have one.

Mike

 

[rdam]

If you don't already have it, install a temp guage. My understanding from some of the senior members is that the 1500 should have little or no coolant. Straight water if possible. Apparently, the anti-freeze disrupts the "natural" convection flow system.

I run straight water with "water wetter" and have maxed out at 235 degrees on a hot, 90 degree day while bush hogging. If freezing is not an issue, I think that's your best bet.

 

[cfoxmd]

As I understand it, without a pump, the 1500 uses natural convection (induced by heat) in the coolant to circulate. If you use more than 30-40% antifreeze, the mixture is too thick and instead of the usual raise in boiling point one would expect with antifreeze, you get a lack of convection/circulation and failure to cool the engine.

So a thinner mixture is preferable for better convection. Some have suggested water with a wetting agent--of course then the fluid boils at 212 degrees (or slightly higher if adjusted for pressure).

I imagine anything less than 30% antifreeze will work, just don't let the engine freeze in the winter.