Replacing alternator belt on 91 ecodiesel?

[Diesel_Zuk]

I picked up my eco from colorado, got it home, supposedly it didn't run, runs fine, just has a leaky IP. The alternator belt was squeaking for a while, but then quit, I popped the hood to find out the belt broke and got lost somewhere along the way. I picked up a new belt, but now when I look at it, it appears to be a rather difficult fix. There is hardly any room. I have power steering and AC, and it is just overall in the way of changing the belt easier. Anybody have any pointers or anything to go about doing this?

[Dakotakid]

Search function.
It will yield results.

[vanbcguy]

The alt belt on the Mk2 cars with AC is a complete pain in the butt.  If you've got the Eco then you probably have the "slip pulley" on the waterpump too - that makes things extra special fun as you can't remove one of the belts completely without removing the pulley if I remember things correctly.  I switched my 1.6TD to a different style of pulleys to get away from that.

The AC compressor belt has to come off at least the AC compressor - you can do that without having to deal with the WP pulley.  But yeah, that whole belt setup is just stupid.  You need to back off the tension on the alt belt, unhook it from the alt and then take the tension off the AC compressor to get the AC belt off so you can remove the alt belt.

Make SURE you get the right belt - don't just go to the parts store and find one the same size, get the actual right part number.  The issue is VW uses metric sizes on their belts.  The closest "standard north american" belt you'll find at a parts store doesn't have quite the right V angle and will end up slipping in short order.  I can't recall the proper belt dimensions but it will cause you a ton of grief if you don't get it right.

Search function.Search function.Search function.Search function.Search function.Search function.Search function.Search function.Search function.Search function.Search function.Search function.Search function.Search function.Search function.Search function.Search function.

What is it with you young guys?

Probably every time he searched he just found threads with someone saying search rather than providing any useful information... Sure makes it a complete pain to actually find anything.

[fatmobile]

Remove the crank pully, remove the old alternator belt, install new belt, return crank pully to previous position.

[Diesel_Zuk]

I did all that, the belt was still way to big, even with the alternator tensioner all the way backed out. I went with a 10x700 mm gates belt, and haven't had any issues yet.

[TylerDurden]

Possible the AC belt is too long. That also makes the alt belt too long.  As the AC belt stretches, the alt belt also needs tensioning.


Kudos on the purchase.

[92EcoDiesel Jetta]

I picked up my eco from colorado, got it home, supposedly it didn't run, runs fine, just has a leaky IP. The alternator belt was squeaking for a while, but then quit, I popped the hood to find out the belt broke and got lost somewhere along the way. I picked up a new belt, but now when I look at it, it appears to be a rather difficult fix. There is hardly any room. I have power steering and AC, and it is just overall in the way of changing the belt easier. Anybody have any pointers or anything to go about doing this?

Did you ever get your alternator belt squared away? I looked at your car when Jboogie was selling it but didn't have room for it otherwise I would have bought it. What did you end up getting it for?

I have a 92 Eco and had the same nightmare with the belts for a few years. Finally ended up removing the AC compressor and made my own alternator tensioner and have had no problems since. There's like 1 or 2 members on this forum that claims they never have problems with the Eco diesel alt belt but they installed all new pulleys. Maybe that's the fix if you want to keep the AC. But even with new pulleys, it's still a poor kluged design.


p.s. most listings for the Ecodiesel V belts are wrong, even the VW dealer has some of the belts wrong. The power steering belt is 11.9 x 650, not 10 x 740 as all the listings say. It's funny but the only place that has the Ecodiesel alt belt correct is Hans auto parts, all other places I have inquired has it wrong.

[Diesel_Zuk]

What about autohausaz? That's where I ordered my new belts from. It's funny, my alt belt just broke again two days ago. I'm planning on swapping it to a 1.9 aaz down the road, so I'm not even going to mess with the pullies for now. And I like having AC, so I'm not going to remove it just yet.

[Diesel_Zuk]

And I paid $1500 for it, she said it wouldn't start, and supposedly it was diagnosed as a bad IP. The IP still leaks, even though I resealed it. I can't figure it out. It was leaking from the cold start lever, and I put new seals on it. It worked fine for about 6 months, until I pulled the lever to start it when it was cold, and it started leaking again. I didn't see any where on the shaft, or anything unusual. Fast forward to about a month ago, when it got cold here, and it wouldn't start. I could pull start it with another car, so I knew it wasn't the pump. I put new glow plugs in it, and it starts up on the first try every time now!! Hooray for me. I have a turbo pump I'm going to put on as soon as it gets warm, along with a set of turbo injectors.

[92EcoDiesel Jetta]

I just checked Autohaus and they have the pwr steering belt correct, hopefully their other belts are too. I know VW dealer, Germanautoparts, NAPA, Autozone etc. have the pwr steering belt wrong for my Eco.


That's a great deal for that car. Good luck with it.

[Diesel_Zuk]

I've had it since march 18th, 2014, doing great so far. I should probably change the oil though, it's at 6,000 miles now, but at least it's rotella full synthetic. Last time I replaced the belt, I used a 10x685mm belt, and it fits great, but when it rains, the AC belt decides it wants to slip, even when everything is adjusted as tight as possible, I can still feel it is really loose. I jumped to the conclusion that is stretched, and ordered a new one. Per another eco owner, he said he used those exact sizes AHAZ sells, and he said they fit great.

[92EcoDiesel Jetta]

I've had it since march 18th, 2014, doing great so far. I should probably change the oil though, it's at 6,000 miles now, but at least it's rotella full synthetic. Last time I replaced the belt, I used a 10x685mm belt, and it fits great, but when it rains, the AC belt decides it wants to slip, even when everything is adjusted as tight as possible, I can still feel it is really loose. I jumped to the conclusion that is stretched, and ordered a new one. Per another eco owner, he said he used those exact sizes AHAZ sells, and he said they fit great.

I don't think you will be able to not have belt problems in the Eco unless you 1. install new pulleys (I've not done it, just hear say it works), or 2. remove the AC compressor and re-rout the belt with a custom tensioner. The stock alt tensioner design is just garbage in that the further you tension the belt, the less pulley to belt contact area (diminishing return). If the alt belt is easy to change no big deal. The problem is it takes a few hours IF you have the right wrenches, which are many. It can leave you stranded. I never felt comfortable driving out of my AAA free towing area while I had the stock belt setup.

[Diesel_Zuk]

I've been driving it several days now without charging the battery, I just don't use the radio, heat, wipers, or lights, so I don't drive it at night. I'm planning on keeping AC, and making a custom tensioner somehow or another.

[TylerDurden]

I found that the best belt life comes from a smooth idle. Mine idles pretty smooth and usually ~900rpm. Really, you can see the damn belts flapping when the engine is idling rough and putting shock loads on the pulleys, alternator and TB. The belts generally run smooth over 1K.

I dicked around with tension mods and took em off.

On my 86 w/o PS, I might re-tension 2, 3 times a year. Takes ~20min to change an alt belt, 25min w/PS (and you gotta go under).

Replacement seems almost a logic puzzle at first, but it ain't that bad:
Loosen alternator belt and slip off alt, lower compressor and slip AC belt off, raise compressor and replace alt belt on compressor, lower compressor and slip on ac belt and tension, put belt on alt and tension.

Keeping all the tensioning parts lubed and corrosion free is a big help. When both belts are new and un-stretched, pulling the WP pulley can help get the AC belt in place (rather that trying to roll-over the lip) and the same with the alt tensioner.

I did dump the slip pulley on my 89 when the PS died and I deleted the belt. PS belt drives the WP on a slipper.

I carry spare belts, and a small tool-wrap in the boot that has 8 & 6 allen, 13mm flexi wrench 13mm socket on 6" extension, 17mm box, stubby 13mm combination wrench.

[Diesel_Zuk]

Sounds like a good idea. Mine idles around 1k for some reason, my guess is timing, because I never time it, I just use the tools, then adjust the pump by hand til it runs okay, and then I tighten it down.  I'm lazy. It seems to have a ton more power the more advanced I put it, but at the same time, it rattles a lot more. I'm just waiting til either it's warm out, or I get a shop with my brother, then I'm going to swap to my new turbo pump, and injectors, and time it the right way.