There are many things that have to be "Right" on this cooling system. If any one
of them are "Wrong" the light will come on. There can be no air in the system.
And the coolant MUST be a 50/50 mix - antifreeze and water (best is distilled
water)

If the cooling system overheats, the light comes on. If the coolant level is to
low, the light comes on. If the anti-freeze mix is incorrect - the light comes
on. If there is air in the system the light will come on.

If all else seems ok, check you coolant mix ratio. Remember - 50/50. No more, no
less.

If that is ok, park on a STEEP downhill grade, facing downhill. With the engine
warm and the pressure cap off, run it at 2500-3000 rpm to really circulate the
coolant. This should burp the cooling system. Top off as necessary with the 50/50
coolant. Replace the expansion tank pressure cap. Give it a road test.

Beyond all that, you probably have an an electrical problem somewhere.

Good luck.

John Rodgers
88 GL Driver

Michael Wagner wrote:

> Folks -
>
> Need some suggestions.  The dreaded flashing red coolant light has come on in
> my '85.  The van isn't loosing any coolant, the main coolant bottle and
> overflow is full, everything appears to be fine.  I've replaced the sending
> unit that is on the main coolant bottle, so that isn't the problem.  Nothing
> else is obvious to me, so I need to start digging into the 'less obvious'.
> Any suggestions are much appreciated.  I know I'm not in any danger from this
> condition right now, but in the even that the main bottle ever does loose
> coolant, I'd like to be aware of it.  And besides, the flashing red light is
> just plain annoying.
>
> Thanks for your help.
>
> Mike W.