"Jeff Morris" wrote in message
...
I'm in the middle of changing the antifreeze in my Yanmar 2GM20FC engines
and am
curious if I should change type.

I've been using Ethylene Glycol, following the advice of a Yanmar mechanic
who
said using Propylene Glycol would void my warranty. I've never been able
to
verify that, and I'm now long out of warranty so I'm wondering if its time
to
switch to the more environmentally friendly Propylene. I also think that
using
the easy to dispose propylene would encourage me to change more
frequently.

Secondly, if I do change, do I have to flush out all of the old, or is it
sufficient to just drain it?

Do you have an owner's manual for the engine? It would probably tell you.
Failing that, contact a local Yanmar dealer. Mechanics are a frequent
source of misinformation.
--
Evan Gatehouse

you'll have to rewrite my email address to get to me
ceilydh AT 3web dot net
(fools the spammers)