Swoopy

I'm amazed at how well this car continues to work as factory stock after 40 years. 1971 olds cutlass 350 with AC manual temp control, plain jane automatic. Doing some replacing of interior and checking wiring and correcting any issues. Well I have found the reason why the blower had stopped, corroded relay.

I have the new blower heater relay and the old, but the factory stock black female clips were done, fried. They were melted and just hanging below the relay. I opened the old relay as suggested from another post and well I’m still lost.

The relay has 4 terminals as noted on the attached wiring diagram. Mine is the same as the attached blower rely with its shown terminals. The relay is behind the brake booster what a pain!

I noted four wires to the relay; 1) main power feed from horn relay with fuse, mine is dark green, 2) a blue wire, 3) a purple wire and 4) a black and orange wire.

From diagrams and reading posts, I believe that I know the route of the wires. The mystery is where the wires connect to the relay. All wiring diagrams show the wires and relay, but do not specifically indicate the connections. One schematic shows a 3-prong plug-I don’t have this, only 4 melted individual clips

The black orange wire I think goes to the terminal away form the group of 3 terminals located close together?

The dark green inline fuse power goes to the middle terminal?

The Blue wire for the high-speed switch goes to one of the rear of two terminals at the opposite end of the relay from the orange black?

The purple goes to the front terminal adjacent to the blue wire?

The relay goes upside down with the single post (terminal) to the divers side when mounted.

I don’t have any other method to locate the correct position. Help solve another mystery.

My442

Year, make, model, and options will help a lot.....

CQR

......

Lady72nRob71

Will this help?

Swoopy

Yes thanks.

I see the black-yellow on the far end. Good that is where I connected mine. Is that connector with the purple wire a 3 prong clip? Perhaps I do have the 3-prong clip, but mine were separate I think, too melted to really tell. I have 4 wires.

By your pic, it appears that the purple is toward the middle and there is one more wire to the front left of the purple. Is there another wire?

Is that an AC car ? I have a wire with fuse coming from the horn relay, I don't see that on yours.

I'm getting closer to solving. Thanks for the nice pic!

Lady72nRob71

Yes - the plug with the purple has 3 wires - the back wire is there but out of view.
Rockauto sells those connectors with pigtail wires attached for like 3 bucks. They have the relays, too.

Yes, purple is in the middle. Wire to the outside I THINK goes through the fuse holder to the horn relay junction. I have this but it is out of view.
The last wire in the back is an unknown color (either blue or light green). I THINK it goes to the blower resistor. When i get home I can check on it.

Yes


Make any new connections with solder and insulate splices with heat shrink tubing.
The wire from the horn relay through the fuse holder to the relay needs to be 10 gauge minimum. Never use crimp connectors in this line - it is the high current one. Use a 30A fuseholder if it needs replacing. Nice black ones can be found at certain auto parts stores (I think littlefuse brand).

69442C

Using the photo shown, the purple wire is in the middle of the cluster of 3. Your power feed from the horn relay will go to the outer left of the purple and the blue will go to the outer right. The purple wire is connected to the blower motor wiring. The wiring in the photo as well as that of my 69 442, both have 2 black with orange wires. The one is by itself and is the smaller gauge of the 2. The other black/orange is a larger gauge and is the one that runs from the horn relay to the top left of the 3 cluster plug.

Swoopy

Here are two pics of my relay. Bottom shows the cluster of posts to the left and a separate post to the right that I think is the heater main switch control.

I have no clue as to how they connect. Rob's pic indicates that the purple goes to center, black/yellow to single post and the two other wires (blue high speed fan switch & green inline fuse power) are mounted to the left.

The internal pic has the single post holding up the right side (in pic), which is across from the ground, so I'm guessing that is the dash heater switch connection. The center wound (magnet) pulls the points open as I was told it is normally closed, so is this where the purple blower feed wire goes?

The two posts on the left open and close the points (circuit) as seen in the pic as a crusted shorter terminal in front to points and the rear terminal is taller also connected to points.

Trying to understand the relay function, the dash heater switch (black yellow wire) goes to the single terminal and controls fan low and medium speed by ground as current is supplied by main power inline fuse wire. Thus the main inline fuse wire would go to rear left terminal as current could flow by points being normally closed across the top over the wound wire to the blower via the middle post. Since the wound part actuates the hi speed blower then it would have to go the front left terminal (crusted terminal in my pic)

Well Am I right?

Rob, I think your pic solved the mystery. Thanks.

Lady72nRob71

The single connector on the right is for the relay coil. It gets its power from the dash switch on HIGH position. The ground is through the case.

The big purple in the middle goes right to the blower.
When coil is energized, the relay contacts pull down and switch power source from resistor network to full 12V from horn relay junction.

Now you talk about a green wire going to the horn relay. Can you tell if it is factory wiring? Is it run through the taped harness? I think the original color is black with orange stripe...

69442C

Without getting into the technical function of the relay, here is how it is wired. The wire to the left of the purple wire is the fused 12V power source.

Swoopy

Thanks all. Rockauto here I come.

From the 3-prong connector, as seen connected in Rob's pic, then the purple is in the center and power feed as suggested by 69442C is to the front and blue to outter right.

But if the main feed goes to the front, then it appears to be isolated from the rest of relay. How does the blower get power for low and medium, through the rear right? And how does the high speed work?

Rob's pic has the front wire of the 3-prong clip appearing the same gauge as the purple, confirming 69442C comments.

Ok so if I connect as indicated then single wire to right, 3 prong clip with purple to center. main power to front left and hi speed, resistor (my blue wire) to front.

Now I'm confused again. I thought I had this figured out, but now I see that I wrong. There must be a circuit under the plastic. The wound (magnet) closes the points when energized, so how could it have power going through wthout closing points? I'm going to apply current and test this relay to understand.
So I think i got the connections, but want to know the workings of the relay and circuit.
Thanks all.

Swoopy

Thanks for the pic 69442C, that absolutely confirms the connection.

Is there a circuit under the plastic? I would like to know how this thing works. In the very least, what activates the points opening and closing?

Swoopy

Rob thank you. Looking at the relay internals I can follow the circuit and now I understand how it works. Simple.

My wiring is just like the pic by 69442C. All wires accounted for and connections confirmed. Mystery solved.

Now to replace with correct pieces.

Thanks Rob and 69442C, Dave.

One of these days I post pics of Swoopy.

Swoopy

After reading my post, I should relax and wait. Apparently I missed a few replies and go in circles.

Time to put down the coffee mug!

Thanks all.

Lady72nRob71

A/C wiring diagram:

This should clear up any more confusion...



Or perhaps CAUSE a little more!
The fan relay coil (single terminal) wire could be either black with yellow stripe OR black with orange stripe.
My car has a black/orange there. Also it has ANOTHER black and orange one from the horn relay jcn.

If this is the case, the small diameter one is for the coil and the large one goes to the horn relay jcn...


The coils is just a magnet that pulls the center contact (purple) to either one contact or the other. It is called single pole, double throw (SPDT).

Swoopy? Is that like Snoopy on steroids?

Swoopy

Rob thanks for the chuckle, still laughing.

The name "Swoopy" came about by a friend razing me over the old sticker of an out stretched owl, about 2 feet wide just above the trunk key, appearing to fly straight back off the trunk in a menacing manor. While the old sticker is gone, the name has stuck.

Your last wire diagram shows the connection of the wires in the relay box. It is quite good. The more I mess with Swoopy, the greater need for manuals.

Looking for the correct 3 prong plug and found some online at Autozone and Advanced, but the gauge is 14-16 not 10. Rockauto site does not mention the gauge, but I’ll call tomorrow. Napa does not list the gauge either so there is another call. The old syndrome of I’ll only look and fix this part never fails to snowball.

Thanks for the assistance and laugh. Tip of the hat sir.

Dave.

Lady72nRob71

Hehe... You now HAVE to post a picture, of the owl, if you want to stay on the site! The bird has been released now, you can't deny it now!!
Neat story...

What I have done in the past is to buy the connector (like the Airtex 1P1010), remove the terminals, pry open the crimps, remove the old wires, and solder the terminals to the existing wires. Time consuming, but what the heck. There is a place that sells these terminals but forgot where.

You could also cut the connector wires 1/2" from the plastic, remove the insulation, solder on to your wires, then heat shrink tube the connections.

Now before doing that, go get a picture of that owl in your signature line...

Swoopy

Hmm... Swoopy has flown the coop. We've moved several times since and the pic is on film! Now that's old.

The removal of wires is a very good idea. I've got one ordered from Napa with 12 guage wires, but I think I'll do your conversion.


Looks like imagination time folks!
Dave.

Lady72nRob71

OWL OR GTFO!!!






Is there a police artist on the forum? We need to make a sketch........

classicjoe

Rob, the diagram you posted shows a inline fuse holder from the resistor. Where is it located on a 71 Cutlass? I replaced the resistor, hear the click when I go through the speeds but the fan cuts off on high...

MDchanic

Just follow the wire from the horn relay to the blower relay - it's in there.

- Eric

classicjoe

Just follow the wire from the horn relay to the blower relay - it's in there.

Thanks Eric, Found It!

Swoopy

Ok, Ok. I' m looking for a pic of Swoopy, the ex may have the pic of Swoopy along with a few well, interesting photos.

I have the parts on the way but had to test, all works good. Blower knocked something then ran like a quiet whirlwind, no noise, grinding or metal sounds, just whipped air. Can you believe that a 40 year old car sat without a touch for the last 8 months, kicked the blower motor with no whining? God I love my Olds!

Now to fix the rear defroster, I swapped out the dash control without rear defrost to a rear defrost. Have wiring. Hooked up. I bet there is a relay involved.

From the dash plug on the rear defrost, there is a brown wire (It is hot power), a white resistance wire with 4 amp inline fuse which circles back to the switch and a purple long wire which I ran all the way back to the rear defrost motor. Ground for circuit.

After checking all connections and felling quite cocky after resolving the blower relay matter (with kind assistance), I felt for sure that the rear defroster would sound like a hummingbird. Well with dash switch on low my test bulb glowed, but not enough power to turn the motor. Next I click the dash switch to high thinking well this will light the motor and poof, nothing, no motor and the test light goes out.

Ah, humility.

I’ll tackle that in the next few days as well as find a pic of
"Swoopy."

I've got the car bug again, kids are old enough, and I now have time and a renewed sense of pure enjoyment. Ah the Olds life.

Thanks for solving my last two mysteries. 1) blue wire-Tracked down the front speaker (still there) and noted blue rear speaker wire. On a side note, I have the original Oldsmobile AM radio in attic cause I gotta Rock, 2) blower relay now works with right connections.

Wish I would have posted first, could have saved me hours of frustration. Now you're all are in trouble, I'm picking brains!

In the mean time, I'm feel'n the need for torque. The olds 425 sitting in pieces in the garage is calling out ... All stock. The guy I bought the motor from said it was a 455 and I didn't realize the cam bank angle issue at first.

I was new to olds back in 1987 when I purchased Swoopy (71 Cutlass) for the motor for my 77 olds.) That 77 rode like a dream, had all the bells, buttons and whistles, and I'll miss her. Kept Swoopy, fell in love with the lines as no other car had an aggressive rear quarter like that, nor the stance, sweet. Lusting, drooling aaaahhaahhh..

Now back to that Damn 425 purchased in 1995. It ran like a scalded dog above 2000 rpm but was missing below. All the car guys I hung with were ford dudes and had not a clue. We drove it a few times during the summer, but called it quits knowing full well that something was amiss with that timing etc... could not change. But hit the pedal at 40 MPH and feel her get loose, yup an adrenaline rush. I now want that torque again!

Later found out the funny cam bank angle. Why couldn't it have been a Tornado with large lifters and the normal cam bank angle? Oh well.

Now back to searching for pics of Swoopy and tracking down the schematic for the rear defrost. Almost giddy, feel’n the pure enjoyment of working on and bettering Swoopy.

Dave.

Lady72nRob71

Did your fuse blow?
4A will not handle a motor's current. I suspect a relay is involved. If there it would be next to the AC evap box on the firewall. Also resistor wire sounds a bit odd, unless it is for low speed. Did this defogger unit come with the car?? Sound like you added it...

The 72 uses the hot grid on the glass so I do not have a schematic of the circuit of the rear fan. Not sure how it is wired.

Swoopy

Yes its an add on. I'll check the fuse and increase the amps. Did not notice another relay. Funny, with the blower relay, it had a straight hot and this rear blower does not. I would have noted a factory large "Hot" run wire all the way to the trunk.

Tested the defroster motor, spins well. I think it may be just the low amp fuse. Reading all posts involving rear defroster and will try to resolve with the wiring diagram.

Dash switch has 3 male terminals and of those, one is a loop back to the dash switch, the brown wire to the wihte wire and the purple to the rear defroster. Should be simple enough right?

Lady72nRob71

Best advice is to obtain a wiring diagram for this option (fan type defogger) and lets try to replicate it.
Wiring running to the motor needs to be 12 gauge minimum, 10 gauge ideal. Not sure about the current capacity of the switch, either. It might require a relay.

The hot grid had a relay that prevented the defogger from working until the engine was actually running. Also another relay locked out the high AC blower speed when defogger was running, since the alternator's output was limited at idle.
Hot grid defog equipped cars in 72 got the 63A alternator.

Do you know the current rating of the motor you have?

Lady72nRob71

Alright, it's been a month.
WHERE IS SWOOPY?