AC Blower Motor / Electrical Issues

[FabCad]

I'm in the final stages of getting the A/C system operational on my 56 Cad. The blower motors in the trunk don't work too well -- one works intermittently and the other turns slowly. Does anybody have experience with these aftermarket blower motors?

http://cgi.ebay.com/ebaymotors/?cmd=ViewItem&_trksid=p3984.m1438.l2649&item=140590215305&sspagename=STRK%3AMEWAX%3AIT#ht_8630wt_948

(eBay item # 140590215305)

Or is there a better source?

["Cadillac Kid" Greg Surfas 15364]

Fab,
If the fan motor turns that is the good news. It is not burnt out, and most probably only needs lubrication.  If there is no lubrication point(hole in the casing where the shaft exits the motor case) you probably can make one.  If you are not comfortable and/or you are not familiar with the construction of small DC motors, I might suggest you take the motors out and take them to an Automotive electric (Alternator/Starter) shop. They can probably help you out.
Greg Surfas

[J. Gomez]

Fab,

Those Delco DC motors can be brought back to life they are very dependable and as Greg states if they still working a bit of cleaning and lubrication will get them going again.

You need to be careful if you decide changing them as one rotates CW and the other is CCW, and reversing the polarity will NOT make the motor reverse the rotation.

Good luck…!

[FabCad]

Thanks for the advice, Greg and Jose. I'll see what I can do to lubricate the motors. I may also have them reversed (didn't realize they rotate in opposite directions).

The motors get very hot after running for just a couple of minutes.
Also, today I discovered two additional electrical issues upstream which may be related:
1. the connections at the A/C control unit under the dash get very, very hot
2. the compressor isn't getting enough power (it works only if I run power directly to it)

Any ideas?

I got the whole A/C system rebuilt and recharged. So once I figure out these electrical problems I'm in business!

Thanks for the help!

[J. Gomez]

Fab,

I would strongly suggest that you take the motors out and slide both bell housings out, inspect and do some cleaning and lubing. As Greg suggested if you are not comfortable have an electric shop do the work.

The complete A/C power is via a single power source with a 25A fuse, and the original wiring was marginal to handle the load. The motors speed is controlled by the two rheostats at the A/C control panel, a trouble motor will cause the rheostats to get real HOT. Even under normal conditions these rheostats do get warm to the touch.

For the other issue with the clutch solenoid;

Set the lever to the far right “Full cooling” this will bypass the climate controls.

Disconnect the “green” and “light gray” (these go to the blower motors) connectors at the control panel.

You may notice the compressor clutch engaging properly.

If you still having problems with the clutch not engaging properly you may need to do some troubleshooting to that circuit path.

Remember the 12V source for the clutch starts at the A/C control(dark blue) it goes to the Evaporator freeze thermostat, then back to the front A/C panel (black) and it connect from there up to the engine compartment to the compressor.  We are talking about a good 30’ of wire from and to.

Good luck..!

[FabCad]

Thanks for the additional information, Jose.

Tomorrow I will attempt to take the blower motors apart and clean and lube them.

I discovered I have a broken wire on the A/C control unit (see photo below). I assume this is the blue wire you refer to. The only thing is I don't see where this is supposed to connect-??

[J. Gomez]

Fab,

I do not have a picture of mine at this moment, my units are somewhere in a box in the garage, and all of mines had the same problem. I have one picture which shows the connector hope this helps.

There are two brass tip connectors at the lever, at the far right side there are two off set brass terminals that mate with these connectors at the lever when you slide the lever to the right “Full cooling” mark.

The two brass terminals are riveted to an insulator which is held by the screw and slides in a square notch at the A/C control.

The “blue” wire terminal is prone to brake since it just sits at the end of the insulator which is very thing.

Your picture shows yours broke and it seems you also lost the piece of insulator on it. In your case you will need to make one and riveted both terminals back. You may still have the small piece with the second terminal that you could use as a template, and just trace the extra length to attach the outside terminal.

Good luck..!

[FabCad]

Today I pulled out the blower motors, took them apart, cleaned and lubed them, put them back together, and reinstalled them. They work great now!!

On the A/C control I made a new insulator piece and reconnected the brass terminal and blue wire. However I am missing the second brass terminal... Not sure how important this is-??

Good news is everything seems to work now and I'm blowing cold air!!  Very cool!!