Alfa Romeo Forums banner

86 Alfa Spider A/C fan

5K views 20 replies 3 participants last post by  Joe Papa Sr 
#1 ·
I am very close to getting the A/C system functioning. My last issue is the A/C vent fan (above passenger footwell). The fan is drawing too many amps to the point when it is lowering total system voltage. The other two fans (heater fan and condenser cooling fan in front of radiator) draw hardly any amps.

Hence, I want to remove the A/C vent fan. I have glovebox removed but how to remove the fan only is not readily apparent. I was hoping to remove fan without removing entire cooling unit.

Can anyone shed some light on my situation?

thanks
 
#2 ·
Check all your electrical connections from the alternator thru the fuse box and key switch. Resistance in the connections can drop the voltage. If you take that fan out, the AC can not circulate air thru the car, in other words, it won't work.

I have the same setup and the there is no problem once I got all my connectors refreshed. I increased the voltage on the meter by 1.5 volts, just cleaning and tightening connections.

Thanks.
 
#3 ·
Reply

Actually I just finished taking the glovebox out and addressing situation. I disconnected the plug to fan motor and checked supply voltage. Then loosened mounting collar of fan seeing if it would "fall out"(lol). I decided I would look at it later so I reconnected plug and tightened mount.
For some reason I was driving around and turned on the A/C fan. System voltage dropped much less. Above idle it remained on 12+volts.
Not sure if it was mount or plug that caused change. I will soon go back and clean plug thoroughly and play with the mount while fan is running. Maybe a can get a little more voltage (i.e. current draw).
It looks like a bear removing the cooling unit if that is what is necessary to remove fan assembly.

Thanks for your info
 
#4 · (Edited)
You are talking about a very common alfa S3 voltage problem "disease". I (and others, Im sure)have been plagued by this for years. Its our below capacity alternators, crappy 65A (I think) ones. You need to but the 85A one from a guy in S Cal. I just got one from him (havnt installed it yet). But I am confident that should help big time.

Here:
http://www.ebay.com/itm/Spider-GTV-...lat-/130792485546?pt=Motors_Car_Truck_Parts_A
 
#5 ·
Thanks Joe Papa Sr

This is great info!

Increasing capacity is certainly a great option. That's a little over 30% increase in output!

I'm saving this info in my files. I'll get system running and just see where the volt/amp readings end up.

Actually, I'll probably end up getting the higher-rated alternator anyway. With both A/C fans running and with the headlights on, I'm suspecting things would be marginal at best.

And what a great price too!


Thanks again sir

Warren

P.S. These forums are GREAT!!!
 

Attachments

#6 ·
This is great info!

Increasing capacity is certainly a great option. That's a little over 30% increase in output!

I'm saving this info in my files. I'll get system running and just see where the volt/amp readings end up.

Actually, I'll probably end up getting the higher-rated alternator anyway. With both A/C fans running and with the headlights on, I'm suspecting things would be marginal at best.

And what a great price too!


Thanks again sir

Warren

P.S. These forums are GREAT!!!
Thanks, Warren. Yes, I believe thats the right direction to go. And so cheap, too! Let me know what happens.
 
#7 ·
To pabeaver

I just realized that you got the impression that I was going to permanently remove the footwell fan.
My plan was to "drop" the fan assembly (lol) and check for binding, bad bearings, bad motor etc.

Your advice on checking all connections was certainly spot on.

I'm just hoping that, when I get it gassed up and cooling, the expansion valve does its thing. I've kept system sealed the entire time.

Anyone happen to know the weight of an R-12 charge? I'll use 80% of value for R-134A.

I use a very accurate digital scale and charge by weight as opposed to gauges and with good success.

Have a great day

Warren
 

Attachments

#8 ·
I just realized that you got the impression that I was going to permanently remove the footwell fan.
My plan was to "drop" the fan assembly (lol) and check for binding, bad bearings, bad motor etc.

Your advice on checking all connections was certainly spot on.

I'm just hoping that, when I get it gassed up and cooling, the expansion valve does its thing. I've kept system sealed the entire time.

Anyone happen to know the weight of an R-12 charge? I'll use 80% of value for R-134A.

I use a very accurate digital scale and charge by weight as opposed to gauges and with good success.

Have a great day

Warren
Warren,

Whaddya mean 80% of the r134a exchange?? Man, that doesnt seem like the right approach at all, I gotta say. First, your system did NOT require R134a, but R12, so saying 80% of R134a is not a good base line measurement! beware!!

Your system used R12, so thats what you have to measure by. Now, My manual is in S Cal , so dont have the R12 weight available, but I recall its near, man, I cant remember, but i will search......
 
#12 ·
Reply

The 80% rule is pretty common.
For example, I just had to replace a bad compressor in my 88 Honda CRX. Factory specified R-12 capacity is 2.0 lbs. I dispensed exactly 1.8 lbs. It cools fantastically (I live in Florida). I'd easily put it up gainst any other CRX.
The same goes for my 82 Porsche 911.
I'm not sure of the physics with the 80% rule but it does work.
It beats looking for bubbles in a sight glass or charging with gauges. These involve a lot of guesswork.
I got a nice digital 50 lb scale on eBay. It's claimed to be accurate to a fraction of an ounce and it is extremely repeatable. I totally trust the readings.
Also, if you have to top off system, you can dispense like maybe 6 ounces at a time out of a 30 lb cylinder as opposed to wasting time (and freon) with the 12 oz cans.
Of course you have to use the proper o-rings, but that's about it.
I highly recommend it.
 
#17 ·
I cleaned the socket for the 20 amp fuse on the left inner fender.
I gained another half volt with fans running just by doing this.
I think I've addressed every connection in system.
Life is good.
Dont forget- the real test for your elec system will be when you start the car with ac on, radio on, and no hesitation with starter. If so, repeatedly, you dont need the upgrade alternator.......

man, good luck.
 
#14 ·
Geez, Tro, youre pretty good at this troubleshooting! Good going! Oh, just called Jr In S Cal, and the manual says 0.7-0.8Kg R12 factory, if you need to reference that at all.

Also, glad your r134a keeps your car cool, as thats a surprise. Also, the 80% rule is as accurate as any other method. There is no established reference on how much r134a to install in an r12 engineered system, to my knowledge, so that figure may have been "passed along" like so many other "rules" to go by on such matters. But, bottom line, I respect your situation, and hey, it works for you, thats all that maters.
 
#15 ·
the idea that 80% is more accurate than psi measurements is maybe not always dependable. In the HC world, for example, commonly asssumed rule is about 35-45% of the r12 capacity, but Ive tried that and different cars vary. Sometimes I have to go 50% to achieve the optimum cooling (checked by thermometer/hand feeling)One does have to use some intuition every time- no simple hard fact method.
 
#16 ·
Oh, and not to worry about wasting part 12 oz cans if youre talking about HC's, as theyre sooooo cheap. Cant even compare. Also, if "wasted" no harm to environment, so one's conscience is clear. Also, no expensive evacuation tools/vacuum pumps. No worry about incompatable oil too.

Just info, thats all. I think you got the system all OK now, Tro.
 
#18 ·
Reply

The way I see it, the manufacturers also charge their new cars by weight. And darn near every one is like a refrigerator. And I can't argue with success.

As for troubleshooting. I spent thirty two years working in large power generating stations in the process instrumentation and controls area. There were times when you were literally under the gun as minutes were literally thousands of dollars until you fixed it.

Needless to say, I have seen and learned a lot in my area and from other crafts. And it was fun!

Later guys,

Warren
 
#19 ·
Using gauges and bubbles

I've never had a whole lot of luck with using gauges. You have to have accurate ambient RH and temperature. And then you have to do it with the car standing still (not much air flow through condenser). And then you need an accurate thermometer to measure air temp coming out of the vents.

And as far as the sightglasses go, never had much success there either. Do you stop when you see a few bubbles, no bubbles, etc? What's the ideal "bubble rate"?

I'm sure if you are good enough, you can get the amount of charge reasonably close.

With the scale, there's no guesswork involved. I feel like I'm doing it to "factory spec" more or less. And it is not a weather-sensitive process.



Have a great day sir,
Warren
 

Attachments

#20 ·
OK, Warren. Looks like you got it under control. Now, dont forget- let us know is the car starts OK with the ac on (youcant tell with only 1 or 2 starts- have to do this over a week or 2- dont let the alfa fool you like it has foled me a few times). That way, no need for the new alternator, right?

Sr.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top