Should the proper v-belt be a pain in the a$$ ? (1500/no AC)

Fiataccompli

Chris Granju
background: A minor detail in getting my derelict 79 X1/9 able to drive to the store get its own fuel.. but the voltage was very low, alternator quite suspect & definitely the belt was not tight enough at the full end of its tension adjustment. Out of a half million very close v-belts I have on hand, even the closest to what I had leaves the belt looser than it should be. So, with old belt in hand to get a belt the next increment shorter,I visited a local parts store...turns out what we landed on was what their database calls for the car I found out later (840mm outside...which actually is what the label on the old belt translates to...so it's stretched I'm sure, of course).

Question is simple...should a properly sized belt be a real pain in the neck to install? I was expecting to simply rotate the alternator, slide belt on with only minor cursing, rotate away, tension & tighten. Looks like with taking the alternator out of both bolts, it will go in place (and hope to have a minute to do it so this evening), but is this normal? This makes it quite tempting to elongate a stock upper bracket (basically, cut & weld on another 1/2-3/4" or so of adjustment), but I've never heard of this being a big deal. Maybe this car has some funky water pump pulley on it? hmmm...really just curious on this. There are a number of ways to resolve this, but I don't have a feel for what's "normal" for this with 99% of my experience with Fiats being twin cam cars (and my '85 has a GM alternator with an upper bracket about a quarter mile long).

thanks in advance.
 
Question is simple...should a properly sized belt be a real pain in the neck to install?
There's not a lot of swing in the alternator bracket so your experience sounds fairly normal. The trick is to put the belt on the alternator and water pump, and start it at the top of the crank pulley. Then turn the crank using your favorite method to walk the belt onto the crank pulley.
 
Personally, I do not like the walk-on method as IMHO (and this is not a slam on anyone posting to this thread!) it is the poster-child for the half-assed mechanicking that plagues our cars and has driven down reputation and value.

Not sure if your '79 is like my '86 w/o AC, but it does sound very much the same based on your original post, in that the correct belt is too short to simply wrap around the pulleys and then adjust by pivoting the alt. To get the correct belt to fit without using the walk-on method, you do have to unbolt*** the alt from both its mounting points, maneuver the pulley of the alt forward so that you can loop the belt around the pulley, and then reposition the alt and bolt it back up and then adjust per spec.

Why don't I like the walk-on method? By definition, the walk-on method stretches the belt so that it goes over the rim of one of the pulleys. And isn't that a major reason why you are replacing the belt, because it's stretched? Not for me, thank you very much, I'll take the time and effort needed to do it my way.

As far as adding material to the adjustment bracket to allow more adjustment, that of course would work to allow the use of a slightly longer belt and make initial installation simpler, assuming the longer throw does not domino effect into other issues such as the alt or bracket getting too close to other components when you allow for anticipated engine movement.

***OF COURSE, before working on the alt, be sure to disconnect the neg battery cable.
 
thanks! OK....it felt like i was going down a black hole. I mean, sometimes you can look at this stuff & say, "yeah, I can do that..." but if you're fighting each step of the way, maybe you're way off course, if you know what I mean. Damned SOHC! Had to say that. OK, I can deal with all the above. I would think pre-stretching would actually make some sense (like changing guitar strings), but I was going down the road Dan described already when life intervened & I shut the lids on the X for the evening. Thanks! Looking forward to no glowing red light soon!

(as an aside, this almost puts another point in my column for how my other X is set up with the GM alternator)
 
thanks! OK....it felt like i was going down a black hole. I mean, sometimes you can look at this stuff & say, "yeah, I can do that..." but if you're fighting each step of the way, maybe you're way off course, if you know what I mean. Damned SOHC! Had to say that. OK, I can deal with all the above. I would think pre-stretching would actually make some sense (like changing guitar strings), but I was going down the road Dan described already when life intervened & I shut the lids on the X for the evening. Thanks! Looking forward to no glowing red light soon!

(as an aside, this almost puts another point in my column for how my other X is set up with the GM alternator)

I did a search and found this from 2013 that I remembered posting, I used a Gates #7325:
https://www.xwebforums.com/forum/index.php?threads/alternator-swap.20801/#post-169007
 
that's what I ended up with also...by measurement & then later the database called for the same. (I usually don't trust parts store DBs for Fiat belts, but go figure here). thanks!
 
Indeed. I'll only assume there is a really good engineering reason. Anyway, thanks to my wife's TPS sensor alerting on her Honda this morning, I went home during lunch & had a second to pop the belt back on...sweet!
 
I discovered the unbolt-the-alternator method a while ago and it certainly works well for that belt. Unfortunately the AC compressor belt has the same problem: long enough to slip over the pulley is too long for the adjustment range. So I have to walk it since unbolting the compressor is somewhat more painful. I too feel really uncomfortable about doing that. But I can't see another way.
 
Chris, I hate to say it but yours is actually less difficult than a '79 that was built to meet California regulations AND with the factory AC option. Because with that combination there is a smog AIR pump above the alternator and a large AC compressor below it, making access impossible. As if that wasn't bad enough, the belt arrangement on this configuration has one belt off the crank turning the AC pulley. Then a second belt drives off the AC pulley (two groove pulley on AC) to run the water pump and alternator. Then a third belt drives off the Alternator (also a two groove pulley) to run the AIR pump. But wait there's more. The alternator is a Bosch unit where the adjustment isn't on the mounting bracket; the alternator casting has an elongated mounting bolt hole and that is your only movement for tensioning the belt. However you don't even get the full inch of movement there because the alternator hits the exhaust manifold. As Larry notes, the AC compressor has even less travel for adjustment on that first belt. Likewise on the AIR pump for the third belt. And all of the listed belts are not correct. I ended up buying a pile of belts in every increment of size offered and doing a lot of trial and error. In the process I modified a couple of the mounting brackets (which are unique to this particular arrangement), used different bolts, welded some of the nuts in place to allow easier tightening, removed some guards/covers/heat shields, etc and still lost a lot off skin of my hands. Even then some belts still aren't really ideal. So I feel your pain, this design is a total F-up indeed!

When the time comes to do this again I will ditch most of what Fiat supplied and install a GM alternator with all custom mounts, hopefully to allow a little easier servicing of the belts.
 
the GM option, which I did a bit as an experimentation (ie, is it really this easy?) on my '85 affords the kind of belt service you probably expect from most cars. Mine stalled at the "it works" phase & I may get to the "it looks factory" point with it at some point, but functionally it's fine. The downside could be that the alternator as tensioned lays a bit farther towards the rear of the car than the factory setup. Neither of my cars have anything for which this would cause interference, nor does it make access for service or testing difficult.

Even though I'd been a long-time 124/TC guy with Fiats, I'd always listened when my SOHC colleagues said to avoid the ones with AC, so I've effectively done so & happily have no experience with the AC configuration.
 
The downside could be that the alternator as tensioned lays a bit farther towards the rear of the car than the factory setup.
That could actually be an "up-side", as it would position the alternator a little further away from the exhaust manifold and it's heat.
Converting to a GM (or similar) alternator can offer several other benefits as well. It would be easy to get a higher output unit to help the borderline charging system. Certainly less expensive than getting a direct replacement stock unit. You might even find a smaller (dimensional) one to offer more room in that crowded part of the engine bay. And it could also be an opportunity to convert the whole arrangement to a serpentine belt drive, as Hussan and other have done. How sweet would that be not to deal with any of this horribly designed V-belt configuration again. Although I have absolutely nothing against V-belts (actually prefer them in some ways), but for this application serpentine might be the answer.

Have you posted pictures or design details of your GM alt install? I know there have been a few such installations described before but I always enjoy seeing what others do.

Unfortunately I live in an area where AC is absolutely mandatory.
 
in my paradigm, all X1/9s have headers, so proximity to exhaust isn 't much of a factor with these, but that may be a bonus indeed. And, whatever the case, there's plenty of room, so a slightly longer belt seems a quite reasonable trade for having to take the whole bracketing system apart to change the belt.

I do not have photos...I tend to rarely have the patience to do the wonderful digital documentation others do so well here & elsewhere in the Fiat world, but next time I have a chance I'll get some photos. It was truly as simple as cut a section from the lower pivot, cut one of the cheesy SBC type upper brackets & bolt (maybe some drilling of the bracket) it in place at the water pump. A cleaner upper mount that is based on (using same mounting bores) the original upper bracket was what I would do ideally...a bit more cutting/grinding & some simple welding. These are 65A Bosch alternators for me as stock & I believe the GM unit I got was 73A, but options on the GM range up to 100 or so if i recall. I just didn't think I had need for more current and purposely wanted to avoid the potential to try to overpower losses vs. actually cleaning them up, if that makes any sense.
 
I agree on all of your points (including the lack of taking pics...guess I grew up in the era where a camera was something you only used on vacations or very special events).

I have a GM alternator sitting in my stash of odd parts. Not sure what specific application(s) is was from, nor its specs. But when I compared it to my '79s alternator mounts it would not be an easy install. Maybe due to my '79 being the odd CA-smog/AC set-up I described, the lower alternator mount (on the cast iron water pump housing) has the exact same profile as the GM alternator body. As in they both have a "male" mounting arrangement (vs one male and one female)...if that is clear.
 
Yes...easy. I do find myself using my phone/camera as auxiliary brain...i.e., documenting things before i take them apart, locations of wires, etc ...and it's great for that!
 
Ha! I did the GM 12Si conversion decades ago. It didn't help the belt nightmare, but at least helped the charging and alternator longevity nightmare. Still, with all the torque on that one belt, it needs yearly replacement, just to be safe. Like a plane in flight, failure is not an option. You do not want that belt failing on the road, as it requires some serious work to replace and tighten. It would be a tow-home situation. Good reason for AAA membership as a back-up. Been there, done that.
 
Yes...easy.
Perhaps you misread my comment: I said NOT easy in my case due to the type of lower alternator mount mine has (it uses an odd-ball alternator with a different pivot mount cast into it).
I do find myself using my phone/camera as auxiliary brain.
But then you have to wait for the film to get developed. {Joking}

Still, with all the torque on that one belt, it needs yearly replacement, just to be safe. Like a plane in flight, failure is not an option. You do not want that belt failing on the road, as it requires some serious work to replace and tighten.
Precisely my reason for wanting to convert to serpentine belt.
Larry, I'm adding some info on the '79 coolant hose/vacuum line thread for you. Thanks.
 
oh, yeah, sorry..not easy.

on the failure/AAA...I guess if you carry a few tools on board (and a belt), neither unit would be too hard to repair on the road, but the GM would be quicker.

Another note on the GM..people could be prone to compare dissimilar quantities when comparing the Bosch to GM in terms of cost. You can get the GM at a chain parts store w/ a lifetime warranty pretty inexpensively. Most of that 'lifetime warranty stuff is pretty awful, but I suppose sometimes you luck out. I think to get a good quality GM unit is likely well in the ballpark cost of a good Bosch (new or reman). In my case, aside from the small mountains of DOHC & SOHC used & may-be-good alternators I have on hand, I happen to have a Bosch 65A unit that the local excellent alternator shop tells me is good & puts out nearly 70A. That's nice & the ability to have that one rebuilt locally is also nice.
 
Well, I thought I finally found all of the correct size belts for the '79 Calif smog spec AC car. But after completing some other work and getting everything reassembled it appears they are still not right. Due to the arrangement of one belt driving the AC, and the AC in turn driving the others, when the AC belt is adjusted the final position of the compressor affects the relative length of the other belts (there are all interactive). So each adjustment step must be performed in an exact sequence. Apparently I did not have everything right when I went through it to determine the belt lengths, because now they are not correct. Back to the beginning.
 
Took a little time away from the belts issue. Getting back to it I've found what might be the problem.

As it has been noted above, the very limited amount of adjustment available makes finding the right size belt difficult. I tad too short and it won't go on, a smidgen longer and there isn't enough adjustment to tighten it. Having tried successive belt sizes it seemed like I needed a "half-size"...something in between the two consecutively available sizes. However I found that the BRAND of belt makes a difference. Depending on the manufacturer of the belt there are minor differences in the lengths and widths and degree angles for the same "size" (part number) belt. The differences are minor but this just might be enough to solve the problem. How the difference in length affects this is obvious. But the width and angle do as well; by allowing the belt to fall deeper into the "V" of the pulley the width and/or angle changes the effective length. So now I will try a couple different brands of the same size belt to see if one works. Like I said, I might have found the answer.

Another lesson I've learned is to remove the water pump pulley off the pump when installing the AC belt. Then reinstall the pulley along with the second belt. Don't ask. It also helps to heavily modify the brackets, mounts, housings, fittings, etc, etc, etc. Again, don't ask.

This belt brand thing could turn into another one of those debates, like what's the best brand of spark plugs or oil to use! :mad:
 
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