Engine Fans: Should they keep going?

[groucho]

A question I should have asked years ago, since I've had the car more than 4. In other cars that I've owned the fans keep on going after you switch the engine off and take the keys out. Why in Griffs (unless it's just mine) does the fans go off when you switch the ignition off?

3 questions, then.

Why does it do it?

Wouldn't it be better that they go off on their own accord after keys have been taken out?

Would it be easy to wire them up like that if necessary?

[jeffsy]

Mine do...I had a permanent live wired up to them so that they overrun. I suppose the only issue there is to make sure that the setting isnt too low as they draw a lot of juice

[griffdude]

They turn off a standard when you turn off the ignition, you can get a kit from mod-wise.co.uk which is 'staged' & keeps the fans running

[unclemark123]

i cant see the point in keeping them running? when you switch off the water pump stops, so at most you are only cooling the static water in the rad!

[spend]

Fans are always live, the otter switch is powered by the ignition - a cap / timer on here to hold them live will do what you want (rather than make them perm live & run the risk of a flat battery).

Dave

[RAW-SEWedge]

unclemark123 said:

i cant see the point in keeping them running? when you switch off the water pump stops, so at most you are only cooling the static water in the rad!

Agree - if you leave the ignition on after the engine has stopped then the air that the fans pull through the rad get cool very quick but the engine is still red hot.

[spend]

There is a fair bit of cooling of the engine and manifolds from the draft created by the fans. I guess it would overcome a lot of the 'hot start' problems as well (but possibly some dead battery ones also)

Dave

[Uncle Fester]

RAW-SEWedge said:

unclemark123 said:

i cant see the point in keeping them running? when you switch off the water pump stops, so at most you are only cooling the static water in the rad!

Agree - if you leave the ignition on after the engine has stopped then the air that the fans pull through the rad get cool very quick but the engine is still red hot.

Perhaps if you added an electric water pump and wired that to run on too.

Fester

[FlipFlopGriff]

The David Beer kit allows you to connect a live to the starter motor which themn allows the fans to run on at full speed after turning the ignition off. The 1/2 speed doesn't continue.
It works too - well, once it has as 1/2 speed kicks in around 80 ish so keep the temp down.
FFG