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Discussion Starter #1
The new structure of the BB has me a bit miffed. The search portion doesn't seem to work like it once did, so I'm tossing this out with hopes that someone has bookmarked what I'm looking for...

My problem is this: the bearing on the A/C compressor is shot, all other components in the serpentine belt path are fine.

I recall reading a discussion here where the compressor could be taken out of the circuit using a shorter belt. If memory serves, someone had stated that they changed the belt geometry during the winter vs. summer as there was no point running the belt past the compressor during the winter.

As always, any recollections or clues would be appreciated. Please note that this is the single-belt, 24V engine.

Sincerely,
 

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I think, trying to remember what I had said before, that it appeared one could remove the upper serp belt idler (straight above the a/c pump) and run a shorter serp belt straight from the lower idler (to the left of the a/c pump) directly to the alt, skipping the a/c pump, and then on to the water pump, etc. Small chance that this may not drive the water pump quite as well, due to less belt contact, but don't know, and better than nothing.

I don't think anyone confirmed this, but it did look like it would work. I was interested in having this option for my LS, the idea occurring during our discussions on making the changes and kit for removing the a/c pump for the 12V.

If anyone has a 24v engine laying about, it would be interesting to try this, and I for one would like to know the length of the shorter belt for the 24v myself so I could buy one and throw it into the get home box.
 

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I run my 1994 3.0 24V in both modes
- with A/C compressor, long belt and one additional idler
- without A/C compressor, short belt.

I attach two pictures showing the geometry.
Both belts are standard sizes.
Coming Monday I will try and find out about their identifications. I do not know them by heart.

Helli
 

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We are curious as to what the belt length is if the a/c pump is left in but the upper idler removed. That is the scenario I see if the a/c pump bearing fails while on the road, until one gets home to remove the pump.
 

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As nice as Helli's drawings are I think this is going to require a sitting engine to tinker on, especially if you are thinking in terms of a roadside emergency.
 

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Well, yes, I'm sure of that.
 

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Discussion Starter #8
Very illuminating diagrams!

And it is clear the A/C compressor and one of the big idler pulleys needs to removed for the shorter belt to work. Definitely not a roadside fix, but it could be accomplished in 2-3 hours. (Provided one is practiced at the "Zen Of Extracting An A/C Compressor Through A Car's Eyesocket", that is.)

I am very interested in knowing the specs on the short belt as it's likely a standard size 7V type.
 

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Del, do you have something like this in mind? (it would allow a lame AC compressor to stay in place). This is pure fantasy for me since I've never laid eyes on a 24v with the fender liner out.
 

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Discussion Starter #10
(eric_h speaking in Del's voice [hopefully, without insult to Del]) "Yes, pinino, that's just the sort of thing which could work. You'd just need to remove the upper idler pulley, compress & reset the tensioner, and be on your way. It might be done with the basic hand tools all Alfa owners carry with them at all times."

The big question would be the belt length. As a temporary fix, a 5V belt could be used. I'll see if I can find out the length of the standard 7V belt...looks like the shortened routing would need to lose about a foot.
 

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Discussion Starter #13
LOL. Yes, I worked out the columns. Conti really should have given some direction there.

I have some spare time tomorrow and plan to work on this. Perhaps I'll be able to add something new to the sum of Alfa knowledge.
 

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Yup, that was my idea exactly some time ago, not having to remove the a/c pump but just taking the upper idler off and putting on a shorter serp belt. Hadn't made a sketch to show that but it looked like it could be done, and was then curious as to what length belt would then be required for the get home box.

Thanks for sketching it out, makes it clearer.

I think it wouldn't be much more difficult than installing a new 12v idler and serp belt by the side of the road as I had to do with the 91S in Wyoming years ago.
 

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Discussion Starter #15
OK, folks. Before I run off to the parts store, I'm going to record this here for posterity.

Getting the upper idler pulley off was easy. You'll need a 6mm Allen wrench in your emergency kit.

The theoretical belt path supplied by pinion will work in fact. As speculated, there's not a whole lot of contact between belt and water pump. But I'm thinking the water pump probably provides the least resistance in the circuit.

I found I had stashed a used serpentine belt in the trunk. So I cut it and measured its length: 77-3/4 inches, 1975mm. Curiously, the Conti site lists no such animal, only 1970 or 1995.

Anyway, after removing the idler pulley and compressing the tensioner, I restrung the cut belt without the A/C compressor in the circuit. While pulling as much as I could, I marked the overlap of the belt end. It was 232mm shorter, or 1743mm.

Consulting, the Conti site, I see they list two belts which might work:

Conti p/n 4070685 (7PK1740, 1740mm)
Conti p/n 4070689 (7PK1750, 1750mm)

There's also a 6V belt:

Conti p/n 4060685 (6PK1740, 1740mm)

I'm going to opt for the smaller belt. Now off to NAPA to see if they can cross-reference the Conti number or use the "Metric Part No." Let's hope I can get past the "what is the make and model?" stage of the conversation.
 

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Discussion Starter #16
Good news everyone. NAPA sells the belt. Their part number is NBH 25070685. None in stock at my local store but they'll have one for me tomorrow.

Their website brought it right up when searching for "7PK1740."

I'll let everyone know how this turns out tomorrow night.

Cheers,
 

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Good work! I'm sure you succeeded at Napa but if not just go to ebay and search "7PK1740", you'll find Dayco, Gaterback, Bando, Gates, etc., the belt is a very common belt for Honda and Dodge. Don't you love the European belt system?
 

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Congrats and thanks for finding this out. When we had been talking about fiddling with emergency kits for the 12V engine a/c pump bearing problem some time ago, I got to wondering if something along that line could be done with the 24V engine with a/c pump bearing failure, mainly since we take our 24V LS on long trips, and haven't replaced the a/c bearing since the car was new (another task for the near future, lol). Glad someone finally took the suggestion and tried it out. Thank you very much.
 

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Discussion Starter #19
The proof is in the pudding tomorrow: belt installation.

With the exception of the failed compressor bearing, this car is a driver. Looks like it's headed to Texas. Whether under its own power or transported remains to be seen.

It would not be the first time I've sold a car to a buyer planning to drive it home...my second Milano headed to Houston and my '76 Spider was driven to Toledo in a single day after seeing only 2000 miles in 10 years! If the belt fits and works, I'd say it would be up for a run to Anchorage.

I'll check in tomorrow with the results of my labors.
 

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Discussion Starter #20
Great success!!!

Belt 7PK1740 works very well. I think the next smaller size (7PK1732) might be an even better fit as the tensioner is sitting about half-way to 2/3's of its travel. But nothing squeaks or squeals at any RPM or driving condition.

Perhaps Steve will add this thread to the maintenance tips thread.

Here's a re-write of all of the above...

Applies to/tested on: 1994 164 LS

Problem: Failed A/C compressor bearing -- pulley on or off.

Solution: Remove existing serpentine belt, remove upper idler pulley, install belt 7PK1740 (alternatively, 7PK1732 [untested].) With the upper idler pulley removed, the belt threads as follows in clockwise direction...

Water pump
Alternator
Lower idler pulley
Crankshaft pulley
Tensioner pulley
Power steering pump

Tools required: 6mm Allen wrench or socket for idler pulley, 15mm socket or wrench for tensioner pivot nut, phillips screwdriver for removing forward half of inner fender liner, tool or improvised toolset for compression of tensioner.

Notes: To compress the tensioner, I typically use a long closed-end wrench (any will do, recommend something 8-10 inches in length) and a couple English Allen wrenches (what else are they good for?) stuck in the idler pulley's holes. Make sure to loosen the 15mm pivot nut first! I insert one of the Allen wrenches through the closed-end into the upper of the two holes on the pulley and insert the other Allen wrench into the lower hole making sure the closed-end wrench is to the left of the lower hole. Pull hard to your right to compress the tensioner.
 
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