411 (1969/1970) cooling fans

john smith · #1 (**permalink**) 28-05-10, 01:26 AM

When my engine (383) is hot (fans running) and I switch OFF the engine, both fans stop.

This is the way it has worked for the past 35+ years.

The other day, the fans continued to work after switching OFF the engine (like I would expect in most modern day automobiles).

Which is correct – fans stopping immediately the engine is switched off (key removed from the ignition) or continuing to operate until the radiator is cool?

Have I had fault for all these years and not known it?

Many thanks -

Peter.Kent · #2 (**permalink**) 28-05-10, 09:32 AM

Can't think why your electrics have changed the way they operate. But, it surely makes perfect sense to circulate under bonnet air and keep that big mass of iron a little cooler. The heat generated by those enormous exhaust headers when at rest is considerable. Stand by the car with the fans running and you will feel the hot air being blown through. ACCS fit an adjustable thermostatic switch and bypass the ignition switch so this all happens in a controllable way. Peter

sjp63 · #3 (**permalink**) 28-05-10, 11:33 AM

Mine stop when the engine is turned off. If ign switch is then moved to pos 1 they will continue to run until thermostat stops them

GREG · #4 (**permalink**) 28-05-10, 04:16 PM

Surely a fan running after the engine has been turned off is only cooling the radiator and not the engine !

Peter.Kent · #5 (**permalink**) 28-05-10, 04:51 PM

No: those two fans blast air through the whole of the underbonnet area. As I say, just stand outside the car when they are running. One car I had, you popped the bonnet to let the heat out. Fans on a proper switch much better. P

GREG · #6 (**permalink**) 28-05-10, 06:13 PM

And I thought that Bristol's were water cooled !

john smith · #7 (**permalink**) 22-07-10, 10:57 PM

Thanks Peter
Though the years past, I often wondered about this but always thought this
is the way Bristol Cars meant it to be.
I also wondered about the drain on the battery if the fans ran for even a
short time.
ACCS???
Sorry, not familiar with them.
Little more information please.

john smith · #8 (**permalink**) 22-07-10, 10:57 PM

Sjp63
Thanks for your suggestion - maybe this is what I did unwittingly, moved to
pos 1 and hesitated.
Next time the engine is hot I will try what you have suggested.
I will follow up Peter Kent's thoughts about bypassing the ignition switch
to the thermostat.
Regards -