Late model RX-7's (93-95) had a recall for fuel/cooling systems for

fires.

This originated from the fact that Mazda tried to run the cooling

system at

19-20 psi which would raise the boiling point of coolant, All they
accomplished was killing the water pump seals and causing coolant

leaks on

top of the engine which resulted in engine fires and a huge recall.

Yes,

glycol based collant will catch fire if the temp is high enough. So be

weary

of people who recommend raising the system pressure without additional
information as to how to eliminate this concern.

Ken Powell wrote:

I had thought that it was quite reasonable to raise cooling
system pressures to 20 PSI.  Is this really a valid concern with
the Mazda water pump?  Is anybody running raised pressures on
their car or their airplane?

Ken Powell

Tracy has shimmed his pressure cap to 30 psi as I recall. Maybe 20 psi.
Had any problems with your water pump seals Tracy?

Paul Lamar

I modified my pressure cap to give 26 psi max coolant pressure.  Still using
the same 1988 junkyard engine water pump I started with 7 years ago.

Tracy Crook
rws@altavista.net
www.rotaryaviation.com

The pump design was changed in 1993 so it could be a problem with 
just the later Kuboto pumps.

Paul Lamar
 
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