Electric fan choice

[NoBeardNoTopKnot]

Me? I've never had an electric-fan cause issues. And 99% of us haven't either. Fitted to most cars in the last 30-40 years they don't go wrong.

Yet.... Until installed properly fans come with a copper-bottom guarantee to be vastly more trouble than they're worth.

Hence no lash-ins.  Fans are grunty, they draw a heap of current thus require decent wiring, proper, proper earthing, likely a relay, and a decent fan / temp. switch. Or they cook. They are brillaint things, and modern cars go 300,000+ miles with the same fan. They have them for good reason. They do not go wrong, however...

If anyone's inclined to simply fire scotch-locks and a few crimps, not use solder in context, forget the relay and hang on a stock S2 loom, and THEN when it all goes wrong - which it will - blame the fan, it'd be far, far better to leave be.

"I've be doing blah for forty years, no problems...  I'm not going near no new-fangled fan/soldering-iron... yadda, yadda" is best for many.

Don't bother, do it right or keep stock.

[TimV]

Here is a picture of the very simple bracket I made - strips of aluminium and a couple of bolts.

[NoBeardNoTopKnot]

Like the mount. V.tidy - looks stock... is that a 14"?

What most don't seem to grasp is that a fan motor pulls at least  4-5 times as much current at start-up, as distinct to running. Inductive load see... That'll fry every fan lash-in. Crimps and switches burn and go HR.

[Craig T]

I fitted a new Autosparks loom to a friends series 3 a while back and that had an electric fan circuit added to it upon purchase. That circuit was sized for a maximum of 40 amps but the fan still managed to blow 40 amp blade fuses. It was a brand new 16" cooling fan from Car Builder Solutions.

In the end I used that existing relay and circuit operated by a temperature switch in the top hose, to control another relay that was rated at 80amps. That was fed by a large wire straight from the starter terminal, into a 70 amp fuse then up to the relay and into the fan.
After changing that circuit and taking the fan load off the little 40amp fuse the fan speed increased considerably and it now cycles on and off as it should holding the engine around 90°c.

The old 40amp fuses didn't really blow as such, they more melted over time.

If you are still running a dynamo I'd be carful of what fan you use as you may start damaging the rest of the battery and charging system.

Craig.

[g6anz]

I've got an ancient Kenlowe fitted to mine. I have that as well as the mechanical fan, and it's fitted with an override switch so I can power it when off roading and there isn't enough air movement through the rad with the mechanical fan. The sensor is not in the rad hose but pushed down the side of the radiator, This doesn't give an exact switch on temperature but by trial and error it comes on at the correct engine temperature. One thing though, I have a light in parallel with the fan motor to show when it running and at about 50MPH this light starts to glow as the fan motor is acting as a generator. I put the 'on' light on the motor rather than on the relay coil as in this position it indicates that the motor is really running and not just that the relay is working.

Malcolm

[NoBeardNoTopKnot]

Purists. Avert thine eyes.

Rather more extreme than required for most - I have lots more going on- here's my bulkhead fusebox (FB). The blue wire that leaves the bulkhead FB goes to the 3 x relay strip blue line in front of the radiator. . The other 2 x relays feed Hi & Lo beam.

If you run heated-screens and such, you'll need to put this sort of thing in. Or it won't work, or.. if it does work, won't stay that way.

The Blue, the grey, the brown, the red, and the brown/black go separate fusebox/ relay strips around the vehicle. Junked the melt-your-loom stock FB years ago. 3-4 25A fuses on hte WHOLE vehicle... jeeeez.

If you fire your lights via separate feeds as shown, expect far, far brighter lights, than thru' the stock and 'oriible voltage-drop S2/S3 toggles & loom. This route has them fed near direct off the alternator. You do have an alternator? You do... good.

[NoBeardNoTopKnot]

I think I put this up before?

If you're considering having things wired such that the fan/heated-screens only get power when the engine runs, you can arrange to fire a relay off the oil-switch. Here's my notes.