Auto Pilot & A/C blowing my fuse... help

[UGW]

I also read this article here: ( Chrysler Alternator Belt Tension Tool ) Question, do I need this part too to set the tension correctly or is there a work-a-around?

It wouldn't hurt if you want to do the job perfectly - factory service manual combines that with a torque wrench for a specific reading. However, I doubt most independent shops had that tool, even in 1966.

I adjusted my belts recently, and I just braced a pry bar between the alternator and the water pump to achieve tension. (Heck, if you're strong enough, you might just grab the alternator with your hand and pull it into position.) Obviously, be careful, the alternator is aluminum, and there is a lot of important stuff in that area, but if you are gentle any lever should work. The problem with this is there's no scientific way to measure the exact tension, so if that matters to you, get the tool. (I'll probably buy one the next time I have an order and already pay for shipping.)

 

[Ross Wooldridge]

Tension is measured by belt deflection - pressing with one's fingers in the middle of the longest span - FSM gives the recommended deflection for each belt driven system, and belts should be retightened after a short period after belts are "seasoned".

 

[UGW]

Tension is measured by belt deflection - pressing with one's fingers in the middle of the longest span - FSM gives the recommended deflection for each belt driven system, and belts should be retightened after a short period after belts are "seasoned".

That's true, and if you're a seasoned mechanic, it's probably good enough. My father is definitely one of those guys who can just push on a belt and know it's right. I'm not. For me, trying to find the exact middle of the belt, push on it, and hold a ruler at the same time to measure 5/8" deflection, with the ruler at an angle where I can read it correctly, feels like comedy.

One good gauge I've seen, is if you can turn the accessory pully with the engine off, but the belt doesn't move, it's too loose. However, this won't tell you if it's too tight, which can also be bad.

It's also true there's a different deflection value for new belts vs old.

 

[Ambush]

The belts are long sadly, and back in the day you used to get a pair of matched belts. They were cut from the same stock piece of belting tube - one after the other.

That doesn't exist anymore.

Regardless, proper belt tension is key, and if the alternator bolt doesn't have the spacer that runs through the alternator and acts as a bushing, plus the other spacer behind the alternator, then you'll get rumble.

I find I have to use an old snow shovel handle to pull the alternator tight enough to get satisfactory tension on the belts.

So if I read you right, any belt I get today at Napa or Autozone that comes up for my make will be longer than they originally would've been back in the day. I guess if it was as simple as just getting shorter belt(s) that are the proper length needed you would've said so. It sounds though, that you're also saying that properly tensioning the belts can overcome the fact that they are longer. Yes? I'm a little slow.

 

[Ross Wooldridge]

No, that's not what I meant...

The belt set that are listed for your application should be the right length from the autoparts store. It was just that in the old days, the you used to be able to buy what's called a matched pair. The "matched pair" is not what exists any more. So you buy two the same length and install them.

They should be the proper length and belt. Tensioning should be the same basic procedure as described above.

 

[UGW]

So if I read you right, any belt I get today at Napa or Autozone that comes up for my make will be longer than they originally would've been back in the day. I guess if it was as simple as just getting shorter belt(s) that are the proper length needed you would've said so. It sounds though, that you're also saying that properly tensioning the belts can overcome the fact that they are longer. Yes? I'm a little slow.

Here's what I recently learned: there aren't really "Mopar belts" or "Ford belts" or anything like that. (At least for old V-belts like ours, modern serpentine can be different.) Just standard sizes. The size (in inches) is usually printed right on the belt, as part of the serial number, but if it's gone you can just measure the belt. Your current belts could be too long, or they could just be worn. You can always try a belt that's just one inch smaller, and see if you can adjust it to the right tension. (1" in the circumference of a circle really isn't much at all.)

EDIT: They might be a little different now, since global manufacturing is largely metric - just like our tires size standards are different from 1966. But, if you get close enough, adjustment can make up the difference.

 

[Ambush]

It wouldn't hurt if you want to do the job perfectly - factory service manual combines that with a torque wrench for a specific reading. However, I doubt most independent shops had that tool, even in 1966.

I adjusted my belts recently, and I just braced a pry bar between the alternator and the water pump to achieve tension. (Heck, if you're strong enough, you might just grab the alternator with your hand and pull it into position.) Obviously, be careful, the alternator is aluminum, and there is a lot of important stuff in that area, but if you are gentle any lever should work. The problem with this is there's no scientific way to measure the exact tension, so if that matters to you, get the tool. (I'll probably buy one the next time I have an order and already pay for shipping.)

Did you happen to see the little demonstration video of the guy using the tensioning tool to tighten his belt? The video link is at the website that sells the tool. I noticed in that video he uses the tool w/ a torque wrench and he doesn't pull on the wrench, he pushes it ( towards the motor ) to tighten the belt ...pulling the tension up from below the Alt. I was thinking in my case I would be pulling on the wrench, tightening the belt(s) by pulling the ALt further away from the compressor, but maybe I have it wrong? Would I need to rotate the Alt forward in? Towards the motor and pulling up the tension from below ...like in the video?

 

[Ambush]

No, that's not what I meant...

The belt set that are listed for your application should be the right length from the autoparts store. It was just that in the old days, the you used to be able to buy what's called a matched pair. The "matched pair" is not what exists any more. So you buy two the same length and install them.

They should be the proper length and belt. Tensioning should be the same basic procedure as described above.

Gotcha! SO my belts are correct ..good to eliminate that part of it.

 

[UGW]

Did you happen to see the little demonstration video of the guy using the tensioning tool to tighten his belt? The video link is at the website that sells the tool. I noticed in that video he uses the tool w/ a torque wrench and he doesn't pull on the wrench, he pushes it ( towards the motor ) to tighten the belt ...pulling the tension up from below the Alt. I was thinking in my case I would be pulling on the wrench, tightening the belt(s) by pulling the ALt further away from the compressor, but maybe I have it wrong? Would I need to rotate the Alt forward in? Towards the motor and pulling up the tension from below ...like in the video?

Well, from looking at the service manual picture in that link, it appears my alternator bracket is on backwards, with the slotted end outboard! It's been that way since I got the car, and it seems to work So don't listen to me, I guess!

I do have the PS belt tool that he also sells, it's great and I recommend it.

 

[Ambush]

Well, from looking at the service manual picture in that link, it appears my alternator bracket is on backwards, with the slotted end outboard! It's been that way since I got the car, and it seems to work So don't listen to me, I guess!

I do have the PS belt tool that he also sells, it's great and I recommend it.

I wonder if mines that way ...I'll look closer. BTW - i found the video link HERE:

 

[Big_John]

I wonder if mines that way ...I'll look closer. BTW - i found the video link HERE:

I have one of those. Nice piece and worth the few bucks he charges. .

BTW, I bought my 300L from him. Chrysler Alternator Belt Tension Tool

 

[UGW]

I have one of those. Nice piece and worth the few bucks he charges. .

If you're going to pay shipping, might as well get the power steering tool also.

 

[Ambush]

If you're going to pay shipping, might as well get the power steering tool also.

Yes that's what I'd do, get both
...but in regards to my question: "am I pulling back on the torque wrench tightening the belt(s), as I pull the Alt further away from the A/C compressor? Or like in the video, would I need to push on the wrench, rotating the Alt forward in, towards the motor and pulling up the tension from below the Alt? Which is the proper direction - push or pull? Reminder- in the video his is a '65 300L w/out A/C ...mine is a '65 Imperial w/ A/C.

 

[UGW]

Yes that's what I'd do, get both
...but in regards to my question: "am I pulling back on the torque wrench tightening the belt(s), as I pull the Alt further away from the A/C compressor? Or like in the video, would I need to push on the wrench, rotating the Alt forward in, towards the motor and pulling up the tension from below the Alt? Which is the proper direction - push or pull? Reminder- in the video his is a '65 300L w/out A/C ...mine is a '65 Imperial w/ A/C.

Apologies if this sounds glib, but one way will make it tighter, and the other will make it looser as you change the belt geometry. You'll be able to tell; just go slowly and you won't hurt anything. If it doesn't seem to work, try the other direction. You should also get a copy of the factory service manual, it will probably tell you. I downloaded mine as a PDF from MyMopar.com and it's been priceless.