How 2 Fix a Heater Blower - Discussion

[Robsey]

This is the discussion thread for a How 2 located here.

viewtopic.php?f=70&t=16697

Based on my exploits in May 2019 after returning from holiday to a non working heater blower.

In my case, it appeared that I was inititially able to save my motor in time, before the bearings got too dry, potentially leading to scored bearing races

Also, despite a few hiccups, I was able to replace my burnt out thermal fuse with a new one.

I apologise if the How 2 is quite wordy, but I tried to cover as much as possible, as thoroughly as possible.

(As an update - Due to this not being the first time that the bearings had dried out, I did have to fit a replacement aftermarket motor a few months later).

[ilovedmymantas]

Thanks for a thorough and descriptive how 2

Mine's needing done, so good timing

Your adaption looks neater & more cooling than the first version.
I tried the blocks last time but did wonder if they were going to collect more heat and cause premature failure
This time I'll buy a new resistor pack, mainly because I can get an aircon one for nine quid just now, I think it's worth it.

I apologise if the How 2 is quite wordy, but I tried to cover as much as possible, as thoroughly as possible.

It's a great how 2.
There's no padding, just instructions that make it do-able by anyone

[Robsey]

Thank you for your kind words.

I really must recommend sprays with straws, as they are the only way to get to the motor spindle.
Especially at the end where the fan drum is located.



You can feed the straw between the fan blades, from the side to get to where the enclosed bearings are located.

[ilovedmymantas]

It's starting to look like diy replacement is the reliable option on cars this age, despite the adjustments needed

Differences for cars with aircon

The motor and resistor pack are separate.
The motor is held on by 2 pretty awkward shallow t20 torx screws.

Although not shielded, the resistor is further from the motor and, i presume the main heat source

I bought a replacement Nissens unit ( 87057 ) because the ad, though vague, showed the correct dimensions.



Cross-references
: 4758819 | 4635041 | 1845021 | 1845035 | 1845038 | 90228758 | 90451605 | 90506193 | 1808068 | 90360146 | 1845057 | 90589511 | 4366944 | 90449576 | 90450963 | 90450980 | 90504705 | 4366746 | 4635330

The resistor pack is held by another t20 screw. Removal of the pack is an anti-clockwise curved motion.




Compatibility
Astra Classic (1999-2002)
Astra F MKII (1992-2001) - Models with 4 speed fan
Calibra A (1989-1997) - Models with air conditioning
Vectra-A (1989-1995) - Models with air conditioning
Cavalier/Carlton MK III (1989-1995) - Models with air conditioning

Interchangeable Part Numbers:
1845789
1845790
1845791
90383817
90450998
90510089

*Information has been copied from the ads I bought from"

there are two lessons I've learnt from doing this


1. Put the rubber strip back in place, that metal seam cuts into the forearms after a while!

2. Secure your torx bit with tape, unless you want to lose another one

[Robsey]

On my non-air-con version, the clamp retaining screws are quite long, and of the Philips No2 cross-head variety.

The main issue is the jaunty angle at which you need to get a normal screw driver into to access the screw closest to the bulk-head.

With or without the scuttle cover in place.

As stated in both of our threads, the after-market drums look correct but appear to require trimming of the upper and lower shrouds to prevent the drums from rubbing them.

On the non-air-con version, the resistor pack is clipped onto the side / end of the motor body, so no separate mounting screw.

Just for info, the resistor packs do get stupidly hot very quickly, hence why they are in the "sucked-in air stream"

Even after only a couple of minutes of running, they become too hot to touch.
Hence the high fuse value of 216°C.

[ilovedmymantas]

On my non-air-con version, the clamp retaining screws are quite long, and of the Philips No2 cross-head variety.

The main issue is the jaunty angle at which you need to get a normal screw driver into to access the screw closest to the bulk-head.

I meant to say shallow headed torx, the screws are about 2" long.which seemed a little over the top to me.

-" jaunty angle" .
What a good description!

[thomas]

following on from my heater blower tantrum post viewtopic.php?f=13&t=16801, will carry on here:

Been out, fuse is intact, visually and meter-tested for continuity. No sign of heat distress to visible areas of motor plug or resistor; by hand the fan drum is not free spinning, stiff but will move and turn all the way around.

Did someone somewhere mention a thermal fuse, or fusible link anywhere? This is a non air-con model.

I'd like to fit an earlier motor type I think, if I can get one, must act today.

[Robsey]

Look on the last post here.

viewtopic.php?f=70&t=16697&p=170084#p170084

A thermal fuse / resistor pack may only give a temorary fix until it too burns out.

A full motor normally comes with the resistor packed fitted too

[thomas]

thanks Robsey, will chat later, I'm off to the scrappy (Thomson's Galashiels) they've got one and resistor pack on the shelf (for years) from an L-plate -amazing!

[thomas]

Got it, it's nice, dusty, mit resistor, missing a (one) rubber vibration insulator, but I'll have spares from the old one. Scrappy people report it has been on the shelf for 110 months roughly 9 years, they haven't anything else Cavalier-ish at the moment, no whole cars or nothing.

Lots of wd40 been applied to the brushes area, bearings etc, enough to run out and wash some muck out. It's running-in on a power-supply. About the best I have is '3 in 1 Oil', should do the job, I'm going to let it penetrate, use gravity etc. to try soak the bearings, maybe a spot of thicker stuff engine oil maybe as per the howtododo-doodah, hope to get it fitted tomorrow, bit too discombobulated today and it'll likely turn dark sharpish once I'm oxter-deep in the scuttle, so better to do tomorrow what you could do today, manana manana.

The new one, excuse motion blur of the drum, it was turning, at low-speed, at the time:

[Robsey]

If you are able to spin it at low voltage, then it should be fine.

I think what happens with the fans is, they can run dry for a short while.
The longer they are allowed to run while dry, the less likely the lube fix will last.

My motor lasted two or three cycles of running dry and then being lubricated to free it up

By the third batch of dry squeaking, the motor was past repair.

Can't complain I suppose.

So the moral is - don't delay, lube straight away.

As an observation - although my car has an R VIN number (1994), it was fitted with an earlier model motor and resistor pack from the factory.

So the second moral is "check the part numbers on your existing parts before parting with your hard earned wages."

[thomas]

Quick update job done. Full marks for the How-To to Robsey, others too thanks for your tips, ideas observations, I really could have it without you, but it would have been a lot more difficult and ponderous.

Wiggling the bits, into place, the motor, the curved cover, the longer plastic thingy bit was HELL I tell you.
Bit more detail needed on the wiggling part, how to wiggle, how to dress for wiggling, wiggling through the ages ... Replacing temporarily the rubber-strip was a priceless tip.

Love this new forum look, some of the missing stuff buttons and things like edit button, logout button/link etc. which were absent before, or didn't work, are present, and work. Hope this isn't just temporary for crimbo or anything like that.

Some un-interesting photos follow. New one in place first, bit of tape still on top-right thingy boltand old one just sitting there:


As the emergency --well that emergency, is now over, you can be at ease, I do declare the holidays un-cancelled, enjoy yourselves folks, eat, drink and be merry. DLTBGYD

[Robsey]

Glad it all got sorted okay.

As for the wiggling and a jiggling...
With my middle-age spread, I try not to wiggle and jiggle too much, in case I cause an earthquake.

It is a bit faffy getting at everything in the scuttle channel, but manageable.

I do like the retro CavMk3OC format, but sadly I am not the boss, so I cannot guarantee how long it will stay up for.

As for the DLTBGYD comment, that is a bit of a 70's throw back phrase... used mainly by Fletch in Porridge.

[Bob Dodds]

Thanks for Heater Blower info. My Cavalier 1.7 TD blower just stopped working completely. Used this "howto" to strip out blower and found stiff fan and open circuit thermal fuse. Fan oiled and freed off and thermal fuses ordered off ebay. If anyone has a better condition fan for sale I'm interested.

[thomas]

I've still got the old motor I took out sitting around, and as I didn't get a train-set for crimbo, this fan motor has had to suffice instead in the toys department. I'll admit I'm puzzled by the matter, and reluctant to throw it away, ever, in case one day it could be fixed economically. Observations are the same as Bob Dodds describes: open-circuit thermal fuse, motor stiff but by no means enough to stop it turning, seized is certainly far too strong a word to describe it.

I've been running it from a power supply that will trip/cut-out at about 5 Amps, and it will run for a few minutes then stop but continue taking current (< 5 amps), does so at any voltage from about 4 Volts through to 17 Volts, if it stops when running slowly on a lower voltage, increasing the voltage does not cause it to resume turning. When it is in this 'stopped but taking much current' condition, there's no discernible heating of any parts, it offers no resistance to turning by hand either in the direction it ought to be turning or backwards, it doesn't push back. Exactly the same behaviour is observed with the polarity reversed and turning backwards, it stops after a few minutes but continues taking modest current. It (the old motor taken out) has of course been well oiled. I haven't yet got around to taking the rotor and brushes out, I did remove then re-fit the circlip but could not retract/disengage the brushes from commutator.

Had too much on the past few weeks to investigate further and put it aside, but remain interested.

[Robsey]

It would be interesting to see what causes this mysterious refusal to spin.

Logic gives only a few reasons.

Electrical -
Carbon coated armature,
Worn, dirty or sticking brushes
.....
Dry solder joints or
Tired windings either of which could break down as they warm up.

Mechanical-
Dry bearings, although this is unlikely if the motor spins freely.

The problem is that you may need to warm the drum in hot water, to get it to slide of the spindle.
And these motors are a bugger to strip, despite being a modestly simple design.

Unusual for me, I actually skipped my old blower motor. Which is very odd because I rarely bin anything. Even if they are broke.