Electric Water pumps

[Daan]

Also Daan's engine-driven fan lost all its blades, quite lucky the £2 Lada version bolts on really eh Daan at least electric fans you can bodge any other one in place fairly easily.

I would like to call it engineering to perfection myself (I think I still have the engineering drawing that paul made to explain the russian lady what we wanted <of a fan chaps, of a fan!>).

I carry that fan now in my spares package whereever I go.

not knocking the idea of an elecctric pump (or fan) as a get you home bodge, but to rely on it with a 100% duty cycle, I still cant get my brain to agree with.

Daan

[sean f]

I had a read about these a will ago and my understanding was,

A normal engine driven water pump needs to pump enough water to keep things cool at low revs, but the volume of water pumped is dependant on engine revs, at high revs it pumped more than was required and also pumping this larger volume used power. i.e it was one size fits all.

An electric pump can be sized better to cope with the intended use of the engine and only pump the required amount. With the intended use being a BIG factor.

I got the impression the biggest use was for drag cars or short sprint cars where they were prepared to have a marginal cooling system to save weight as the engine was only used for a short burst then given time to cool down whilst idling or switched off with the water pump still on to keep things cool and avoid hot spots.

[Steve Hiatt]

One other bonus with an EWP is that you can bleed the system with the engine off. You can hear it gurgling and bubling and make sure you clear any air locks.

[Boydie]

to add my 10 cents worth, some moths ago, influenced by this forum I switched to a Craig Davies 16" fan, it didnt reduce the normal running temerature but the engine was noticably quieter, so much so I never noticed that the motor had burnt out - I noticed this at the top of a steep winding climb when I smelt the antifreeze saw the temp guage climb past the 140 degrees C mark followed shortly after with the plastic header tank exploding !!!!! Consequently following a tow truck ride back home the original fail safe centrfugal fan is back in situ.

My radiator was long ago fitted with a 1/2" tube 4 core out of a mack truck (cut down) that had a Cummins signature engine, it carries around 1/5 greater capacity with reduced air flow resistance.

The electric cooling pump sounds a good idea on paper but for long distance touring ................ no thanks, I'll stick to the mechanical and carry a spare.