AC Fan intermittent issue

E28 technical advice asked and given! Troubleshooting, modifications and more.
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Notaweekend
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Joined: Aug 06, 2018 12:54 PM
Location: NYC

AC Fan intermittent issue

Post by Notaweekend »

A few weeks ago I was driving with the AC on at the highest speed. I drove for an hour to my destination, and halfway through driving back the fan just stopped spinning. A few days later it turned on again when I pressed the switch and turned the fan speed control up. That lasted until yesterday I got in my car and I had the ac on for 2 minutes then it just stopped spinning.

I read it could be the switch but I'm unsure if it would be the high pressure switch or the switch in the cabin that's a part of the climate controls. When I press the blue switch inside the cabin it lights up, and when i turn the fan speed control to 1 or 2 or 3 the light loses it's brightness.

Could it just be as simple as replacing that blue switch or what do you think?
Mike W.
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Re: AC Fan intermittent issue

Post by Mike W. »

It's not the high pressure switch, the only thing that does is cut out the compressor, it does not affect the fan.

My first guess would be the fuse/fusebox. The old style bullet fuses were not the greatest design, especially at higher amperages. Make sure the fuse looks clean and not burned, is a ceramic type, plastic body and glass body both have issues, and that the fuse is tight in the fuseholder. You might have to bend the tabs a little bit.

It could be the switch, but I'd go for the fuse first.
Notaweekend
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Re: AC Fan intermittent issue

Post by Notaweekend »

The first time it happened I checked the fuse it was ok. I replaced with a new one just to see if it made a difference and nothing. Was running the same fuse when the fan started to work again a few days later
Foonfer
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Re: AC Fan intermittent issue

Post by Foonfer »

I went through A LOT of AC issues a couple years ago. One thing I would recommend doing, just to rule it out, is to lubricate the shaft of the AC "hamster cage". You can do it with no disassembly, just get some very light oil (the kind used for sewing machines, for instance), a squeezable bottle and a long, thin, flexible applicator (12" long x 1/16" diameter approx). I found one on Amazon, oiled the cage, and it started spinning.

There's the fuse issue. The switch issue. The auxiliary-fan resistor issue. And of course... the compressor issue.
garageboy
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Re: AC Fan intermittent issue

Post by garageboy »

Foonfer wrote: Jun 14, 2021 9:51 PM There's the fuse issue. The switch issue. The auxiliary-fan resistor issue. And of course... the compressor issue.
Oh no! Not the compressor!! :shock:

I recently bought an exact 1988 supereta compressor from a junkyard in Flushing and am in process ofassembling everything to get it evacuated/charged... Fingers crossed... Hope your A/C has been behaving since the rebuild!!
Foonfer
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Re: AC Fan intermittent issue

Post by Foonfer »

garageboy wrote: Jun 16, 2021 4:01 AM
Foonfer wrote: Jun 14, 2021 9:51 PM There's the fuse issue. The switch issue. The auxiliary-fan resistor issue. And of course... the compressor issue.
Oh no! Not the compressor!! :shock:

I recently bought an exact 1988 supereta compressor from a junkyard in Flushing and am in process ofassembling everything to get it evacuated/charged... Fingers crossed... Hope your A/C has been behaving since the rebuild!!
I'll have to ask you the whereabouts of this Flushing junkyard with E28 parts... My AC works, nominally. I believe I'll have to bite the bullet and do what everyone says you should do - get a Parallel Flow Condenser up front.
Notaweekend
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Re: AC Fan intermittent issue

Post by Notaweekend »

I would also love to know about this junkyard in flushing.... can you remove parts yourself?

I’m waiting on used switch from friend in the mail. By switch I mean the blue button.

When you press the button, you can hear the compressor activating. Fan does not turn.

When you turn the fan speed up, the blue light gets very dim.

I thought it was spinning freely but it is not. I tried with popsicle stick. Possibly bad fan

Unless it needs to be lubed as you said, and it’s stuck some how. Just imagining things - I think if it was stuck I’d hear a noise or it would budge a little.

Not sure yet!
garageboy
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Re: AC Fan intermittent issue

Post by garageboy »

Foonfer wrote: Jun 16, 2021 10:17 PM I'll have to ask you the whereabouts of this Flushing junkyard with E28 parts... My AC works, nominally. I believe I'll have to bite the bullet and do what everyone says you should do - get a Parallel Flow Condenser up front.
Nonsense. They're just trying to sell you shit. Mine worked fine for 32 years, converted to R134, until I overworked it on my cross-country road trip. The stock condenser is fine. The stock compressor is fine. By 1988, they really got their shit together with the A/C. I suspect mine will be fine after I finish putting it back together.

Once I get it back together and bring it to that cool (no pun intended) A/C shop in Maspeth for charging, assuming it all works fine, I'll have you over on a warm day to drive my E28 and tell me what you think. We're overdue for hangout time.

The junkyard is Roosevelt Auto Wrecking, 127-43 Willets Point Blvd, Corona, +1.718.429.9059

But please be aware that I went to some used car parts website and searched for an E28 A/C compressor, and magically, it landed there first. I called, they still had it, I went over and picked it up. It's that total shithole neighborhood near Shea Stadium, er, I mean, CitiField. So I really doubt they have any more E28 stuff of significance. They were very nice people, but that neighborhood looks like something out of Mad Max... Hope this helps...
MattC
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Re: AC Fan intermittent issue

Post by MattC »

Sorry to jump in here, but Mike W mentioned the ceramic bullet fuses. Does anyone have a good source for these? Everything I find is actually hard plastic, which are not holding up well in the 25A applications.
vinceg101
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Re: AC Fan intermittent issue

Post by vinceg101 »

MattC wrote: Jun 18, 2021 10:18 AM Sorry to jump in here, but Mike W mentioned the ceramic bullet fuses. Does anyone have a good source for these? Everything I find is actually hard plastic, which are not holding up well in the 25A applications.
That is becoming harder and harder to find lately. I found this seller online:
https://www.buslab.com/category-s/231.htm

Part of the secret in finding them is to look at both VW and Mercedes parts sellers since they use the same fuses also. I think the Big A has them also.
I heard an ugly rumor that the manufacturer (Flosser) was discontinuing the ceramic ones, but that was unverified. My advice is if you find them, stock up.
MattC
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Re: AC Fan intermittent issue

Post by MattC »

vinceg101 wrote: Jun 18, 2021 12:04 PM
MattC wrote: Jun 18, 2021 10:18 AM Sorry to jump in here, but Mike W mentioned the ceramic bullet fuses. Does anyone have a good source for these? Everything I find is actually hard plastic, which are not holding up well in the 25A applications.
That is becoming harder and harder to find lately. I found this seller online:
https://www.buslab.com/category-s/231.htm

Part of the secret in finding them is to look at both VW and Mercedes parts sellers since they use the same fuses also. I think the Big A has them also.
I heard an ugly rumor that the manufacturer (Flosser) was discontinuing the ceramic ones, but that was unverified. My advice is if you find them, stock up.
Thanks! Just ordered a bunch of the 25A and 8A. They note that it's only been possible to source the plastic version for the 16A, so I'll have to keep searching for that one.
RonW
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Re: AC Fan intermittent issue

Post by RonW »

Those old fuses are two-part. Would it make sense to keep the ceramic part and transfer the metal part from a new plastic fuse over to it?
MattC
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Re: AC Fan intermittent issue

Post by MattC »

RonW wrote: Jun 18, 2021 1:01 PM Those old fuses are two-part. Would it make sense to keep the ceramic part and transfer the metal part from a new plastic fuse over to it?
That's a great thought. I'll have to take a closer look to see if it can be done without damaging the metal portion.
Mike W.
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Re: AC Fan intermittent issue

Post by Mike W. »

They appear to be available from a variety of places online. Of course some may say ceramic while being plastic, but such is life, also a bonus shopping from someplace that has easy returns. Even Alibaba shows them in both retail and wholesale quantities. Somehow I doubt returns would be as easy as the place up in Washington though.
bert poliakoff
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Re: AC Fan intermittent issue

Post by bert poliakoff »

Right now, Maximilian import is offering a set of them in various amperages for a touch under $30
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