Heater fan panic - over!

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richardw
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Posts: 1292
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Model: Elite S2.2 Automatic
Colour: Essex Blue
Year: 1981

Heater fan panic - over!

Post by richardw »

I've taken the centre console panel out to (a) replace the fibreoptic light source and bulb, and (b) find out why the heater fans aren't working.

The former was completed OK - the bulb needed is a Lucas 989 12v 5w by the way.

My first check on the fan was the switch. The high and low resistance returns are fed to earth via the switch. Both return wires were registering around 12.5 volts, and earthing correctly through the switch. This worried me; if the return wires were carrying that voltage surely the fans should be working? So out with the glovebox to access the connectors for the LH fan. The fans are fed by an orange wire from the fusebox, and this also showed 12.5v. I then remembered my mistrust of multimeters (or more accurately the person using them) and connected a 21w bulb to the orange feed. No glow! That must mean there is high resistance between the fan and the fusebox. Checked the fuse - all OK - then adopted the Lotus position and investigated the connectors at the back, next to the pedal box. Fortunately it was the end fuse of the lower bank, so reasonably easy to get to. There are two pairs of orange wires on this fuse - one for the radiator fans and one for the heater fans. Removed both - they were quite loose and looked very dry - applied Rail-Zip (which I use on all electrical connectors), compressed the female connectors to grip the spade tightly and put them back on. The fans now work!

Now my dash is in bits, there are of course other jobs to do:

- Clean instrument lighting connector up at fusebox - they are dim and the circuit is only reading just over 11v;
- Check the heater vacuum controls - they weren't working as they should, and I've already found a kinked vacuum pipe;
- Tighten the wiper motor mounting - one of the screws turns without tightening so the rivnut has probably pushed through;
- Clean and trim the covering on the centre panel so that the switches clip into place neatly.

I've also treated all my switches with Rail-Zip to deal with any potential resistance/overheating issues there.

As always one job has turned into many so the car will have to tolerate being left in bits for a few days.

Off for a cup of tea...

Richard

Cheers, Richard

Edit - the product I use is Rail-Zip, not Rail-X as I originally wrote.
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Pete Boole
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Re: Heater fan panic - over!

Post by Pete Boole »

Sounds like you've had a good weekend! The wiper motor is secured onto the fibreglass with "jacknuts" - they are like plasterboard fixings. They are also made from thin mild steel - zinc plated - and rust very readily. You may find that the threaded part has rusted off inside the cavity. Usually an easy fix though.

Pete

richardw
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Model: Elite S2.2 Automatic
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Re: Heater fan panic - over!

Post by richardw »

Thanks Pete, I think it was a good weekend but I'm slightly in the doghouse for not contributing more to the running of the house!

I didn't manage to remove the wiper motor fixing but the thread had partly stripped by the feel of it. So I inserted a rawlplug, used a woodscrew and it is now perfectly sound! I do tend to use rawlplugs now in all the places where a self tapper was simply used to screw into the fibreglass to secure trim. The problem of locating the trim panel (when you can't see the hole) is solved by inserting a nail into the plug, then you can locate the trim accurately.

I've managed to claw back around 0.5v for the lighting circuit by cleaning everything up. There is a very slight voltage drop across the fuseboard, but about 0.5v across the switch. A relay looks tempting! But that's the trouble - jobs breed like rabbits once you start and I really want to drive the thing.

Cheers, Richard
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MetBlue
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Model: 502 Elite 1974
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Re: Heater fan panic - over!

Post by MetBlue »

jobs breed like rabbits once you start
I know that feeling Richard. :roll:
Tony
What goes together.... Must come apart.

Pete Boole
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Re: Heater fan panic - over!

Post by Pete Boole »

I've just finished my relay/fuse board (not wired yet) - 18 relay bases and 54 fuse spaces. That should help the car not catch fire! Does your car have the Excel loom Richard?

Pete

richardw
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Model: Elite S2.2 Automatic
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Re: Heater fan panic - over!

Post by richardw »

No, it's the Elite loom. I'd have preferrred an (early) Excel one, but now I've been through most of it, although still not worked everything out.

Your electrical project sounds brilliant!

Off to do some work on an idea for the rear hatch drain holes. It is not an engineering solution, more a 'suck it and see!'

Richard
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richardw
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Joined: Wed Feb 06, 2013 15:06
Model: Elite S2.2 Automatic
Colour: Essex Blue
Year: 1981

Re: Heater fan panic - over!

Post by richardw »

OK done some research and ended up on a couple of dodgy sites. My idea was to use something like a teat from a feeding bottle, cut off the end and attach it to the underside of the rear hatch gutter so the water can drain into the teat, then attach the drain pipe (or a thicker one). That way, with the drain tube being fully flexible, there shouldn't be damage from accidental knocks etc.

I found out all sorts of things you could do.

However my sensible brain then took over and I reckon that the boot off a steering joint could do the job. Cut all but the first bellows off and attach the flap to the underside of the gutter. Mini ones look ideal and they are cheap. So with my patent Loctite rubber seal adhesive it might work. Will let you know.

Somewhat off topic now so will post the result in the proper place!

Cheers, Richard
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Pete Boole
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Re: Heater fan panic - over!

Post by Pete Boole »

I see now why it was a "suck it and see" idea!! :wink:

Pete

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