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AC Help!

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Tophatchef

Jedi Hopeful
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My car, 1989 xj6. It's AC is cold, just not blowing hard enough. It will blow harder as speed increases, like 60mph+, but below that, even on high, my AC is just a small breeze. Please tell me it's something cheap. I've got a black car in 90 degree Florida weather.
 
Check that both blower motors are actually working. If only one works, it tends to just blow air across to the other side. There is a blower in each footwell, up close to the firewall. It is easiest to remove the underpanels to check, but you can just reach up and feel them.
 
Sorry, I was interupted by a customer with a nice 120 DHC.Duty called and all that. Is your car still R 12 refrigerant, or has it been changed to R 134? I find that if it has been converted, that it will often cool better on the move. It can also be a sign of slightly low refrigerant level, no matter which is used. My 93 does this to some extent with R 134, even tho the charge is fine. I have electric fans ( No engine driven fan at all), and see a drop in outlet temp when the fans kick in. I think that the condensor might be a little small. If everything checks out OK, you might look into fitting a pusher fan behind the grill to improve the airflow.
 
I hate R134a. My XJ-6 is still on R12 thank you. I rebuilt it myself. Next rebuild i'm going with something like Freeze12, but not R134a.

If only one of the blowers is running in your XJ-40 (not XJ-6), then most likely it is the Darlington Transistors circuit board. (a known isasue in the XJ-40 blower system after a certain mileage). This is not a cheap or easy job. Lots of dismantling just to verify the circuit board is the problem.

You need a Factory Shop Manual, do you have one already?

there is a guy who rebuilds these circuit boards with new equivalent and more reliable transistors, but you have to remove the board and send it to him.

Let's hope it is not that. It has been extremely hot in Florida this week.

Ex
 
I think it may be one of the blower motors, and I really hope it is. The refrigerant should be fine. I believe it was just charged before I bought the car under a year ago. I'll try to check the blowers when I get a chance. I've been avoiding car work until the early evening when the sun has mostly dissipated.
 
if you think it's one of the blower motors, then it probably is the grime, oxidation, and the rud of the centuries in the Ground connectors' surfaces preventing good contact. Nothing but a maintenance issue.

such was the case with mine back in 1998, though my XJ-6 climate system (Delanair II) is different from yours (Delanair III).

These blower motors RARELY burn out. So do not assume the motor is bad, instead just pull it and clean it. Test it with the car's battery. If good, apply DiElectric Grease to the male and female spade connectors after cleaning the connectors with alcohol.(auto parts store, Permatex 67VR). This grease prevents a re-ocurrence of the problema.

Ex
 
Strongly advise you investigate the constitutents of Freeze12, before installing it. It is EXTREMELY dangerous and flammable.
 
yes, I have heard about the flammability of Freeze12. But there are other refrigerants now, which work a lot better than R134a. A friend in Canada charged his XJ-40 with one of those other non-flammable refrigerants (I forgot the Brand), and he has been very satisfied as I understand.

I guess my point is that there are alternatives to R134a, a refriegerant which is known to be crap. We don't need a product that can't keep up with Global Warming, do we?

Ex
 
FYI:

Freeze 12 and some of the others are just Propane or Butane, so make sure you don't have any leaks or get into any wrecks.
 
R12 is NOT flammable. But when exposed to open flame turns into mustard gas, like was used in the trenches of WWI.
 
Phosgene.
We had the issue on subs with burners and scrubbers.
ANY freon in the air that went through them, Phosgene was what came out.
 
the chlorine and fluorine atoms were added to make the methane molecule not to be so explosive/flammable. BTW the refrigerant molecules are very stable, heavier than air if you put a squirt in a can with out a lid it will stay there, not magicly zoom to the ozone. Where does the magic ozone depleting chlorine atom comes from? hint take a look at solid rocket fuel. very interesting highly unstable and mechanically delivered to the ozone layer. tt
 
Right, well, here's where I'm at. It's god awful hot outside, so I haven't really had much time to look at both blowers. I did however, manage to look at the passenger's side, and didn't see anything wrong, but I don't really know what I was looking for, and I was having difficultly removing the glove box lining, and I couldn't find anymore screws to remove. Well, hopefully tomorrow, or Saturday I can take a look at the driver's side. I do have a question about some water leaking from both sides' blowers (or so I assume). It feels like just water, maby with a slight oily feel to it. It's not so much a problem yet, more so a nuisance.
 
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