Help IDing Water Pump Pulley and Alternator for Belt Replacement

[PB Co]

My alternator belt is frayed/starting to split and I do not want to be left stranded. I have only had my car about a month but I am having trouble identifying my water pump pulley and alternator. A new SpecialT alternator is on hand but I have had no problems with the current units performance. Except that it appears the belt tension is so great that it is pulling the alternator out of alignment.

Forgive the terrible photos, I was only trying to capture the belt numbers. Am I looking at a combination of replacement parts from the crossover list? My preference is to sort it all out at once and I do not want to just throw the same type back on there.

2787327874

[PB Co]

One more photo.

Currently running 9530 GATES Green Stripe XL 13A1345 and 9480 Gates numbers worn off.

27877

[hmcelraft]

The AC belt is a 9530 - that's correct.

Alt/water pump belt OEM is a 7495 NAPA or Gates, etal. A smaller pulley is on many replacement alternators - Delco types - and they use a 7490 NAPA or Gates number. NAPA Gold belts are my favorite - heavy duty. Looks like the alt in the picture is not OEM and has a small drive pulley - so probably the 7490 is your belt. Also, I cannot see the belt tensioner in the picture or the nut that holds it in place. If the tensioner is missing that may explain why the alt may be out of alignment. It is difficult to tighten the alt bolt enough to hold the alternator in place for very long without a tensioner but, it can be done.

BTW, The special T alternator probably came with a 7490 - they typically have the smaller pulley.. http://store.delorean.com/p-6810-bkt-belt-tens-reg.aspx

[PB Co]

Really appreciate the input. I believe the tensioner is there and I will get some better photos tomorrow.

I have Hervey's 120 Amp but scored it in a raffle without any belts. Pulley is only 50mm.

For now I will probably just buy the NAPA Gold you recommended an attempt to adjust. This crusty unit gives me 13V at idle with headlights on and 12V with the AC on according to the dash. Still, very tempting to install Hervey's upgrade.

I read up on water pump crossovers. Did my water pump pulley come from the Volvo list and isn't spaced properly?

[hmcelraft]

The pump pulley looks OEM and was removed and reinstalled from what it appears. A little rough but, it looks to be pressed all the way on to a later pump model that many people have. The pump pulley appears to have no major deformities. Does it line-up with the crankshaft pulley when you look straight down from the top of the water pump? It appears to have been in use for a while.

[PB Co]

The pump pulley looks OEM and was removed and reinstalled from what it appears. A little rough but, it looks to be pressed all the way on to a later pump model that many people have. The pump pulley appears to have no major deformities. Does it line-up with the crankshaft pulley when you look straight down from the top of the water pump? It appears to have been in use for a while.

Yes, the water pump pulley and cankshaft pulley appear straight. If it's just this alternator throwing things out of alignment, then great, easy fix. My fear is that if the pulley isn't properly spaced then I am dealing with two unknowns instead of one. Assuming the alternator bracket hasn't been permanently modified to accept this alternator I would prefer to return to a known solution, so at least I have the SpecialT unit.

I bought the car without a lot of documentation. I have been pleasantly surprised to have found things like a DMCH radiator and some new cooling systems components. New headlight master switch and LEDs already in place. That said, it has been outside for about the last two years under previous ownership. Although everything works now, I want to stay ahead of what I can to keep it a running car.

[D Knight]

Napa gold is a gates. Just go to oreilly and get the Gates. great belts.


-D Knight-

[PB Co]

Unfortunately we are without O Reilly's round these parts, even though I've heard them advertise on Philadelphia radio stations.

I'm going to order two of the recommended 7490 from Napa and go from there.

[PB Co]

Wow. Looks like a generic tensioner combined with a homemade bracket. No wonder it doesn't fit in there properly.

I don't see the original bracket. Guess my first DMCH will be more then a set of keys.

27938

[D Knight]

I see you are in Jersey, call MW. You'll see your order faster and get awesome service


-D Knight-

[PB Co]

Darn those up side down photos.

Maybe I will give MW a ring about my alternator woes and spread the project around to all the vendors. I already reached out to a PO via Facebook last night. Maybe they still have the bracket. Doesn't hurt to ask.

Is this a location where bolts break? I'd hate to get it all apart and have to put the mystery unit back on.

Still waiting on historic tags to show up so there is time. I'm sure all the vendors are feeling the DCS deadline.

[DMCVegas]

Trying to see that belt a little better. Is it fraying on both sides, or just the inner one?

[PB Co]

Trying to see that belt a little better. Is it fraying on both sides, or just the inner one?

Some of the damage can be seen on the water pump in the photo of the pulley. Only the alternator belt is fraying, more towards the outside of the pulley/further back.

Also, I am having trouble visualizing how to get the alternator belt off/on over the AC belt. The service manual indicates this is not an issue but isn't specific. "Remove Belt"

[DMCMW Dave]

Loosen but do not remove two horizontal bolts thru the a/c bracket. The loosen the locknut and the long bolt at the bottom of the bracket. Slide the bracket up to release the belt tension and take off the ac belt. Put back tight in reverse order


Sent from phone

[DMCVegas]

Some of the damage can be seen on the water pump in the photo of the pulley. Only the alternator belt is fraying, more towards the outside of the pulley/further back.

Also, I am having trouble visualizing how to get the alternator belt off/on over the AC belt. The service manual indicates this is not an issue but isn't specific. "Remove Belt"

Gotcha. It may be pulley misalignment since there isn't an OEM bracket installed, and/or something is bent. Still though, I'd check those pulleys for any sort of wear or damage to ensure you don't have a possible nick in one that is slowly chewing that edge of the belt. I had a problem with my car when I first got it where the alternator blades were bent and damaged. As you increase RPMs, the Alternator blades will naturally flex and bend outwards. Mine were already bent and would go out too far, so at about 4,800 or so RPMs it would make contact with the belt and just start chewing away. But in my case, the damage was to the inside edge of the belt/pulley that faces the engine.

Dave is right: You have to remove the A/C belt to get at the alternator belt. It's not a difficult job at all. As you see, Dave has you covered with the removal of the A/C belt. The Alternator belt IMO is slightly more difficult, but very easy all the same. Loosen the bracket and push the Alt. in. Then just drape the belt over the Water Pump, Crank, and Alt. and pull the Alt. out just enough to pretension the belt. Finger tighten both bracket bolts. Then get down and lay of your back. I like to use a Floor Jack Handle personally, and the I'll come from behind the Alternator, between the Alt. and the Engine Block. Pull the handle/breaker bar down and press it against the side of your alternator and leverage the other side against your engine block. Pull out on that bar with one hand, hold the tension, and then tighten the block bolt to hold your Alternator in place. once that's done, tighten down the rest of the bolts and you're done!

The Workshop Manual isn't quite on par with Chilton, Haynes, or even modern OEM. It was constructed from different manuals, and is written more for a mechanic rather than a regular shop tech, let alone a DIY'er. There will be little idiosyncrasies like this, but you'll get used to them.

[PB Co]

Can't thank you guys enough for the input. I know this isn't a big job, but it is a big job to me and I like to be as prepared as I can.

Dave, you just saved me hours. Thanks. I'll ring you guys after DCS about my missing bracket/tensioner.

Robert, will definitely inspect pulleys. I know water pump and crankshaft all spin straight but I have not yet looked for damage to the channels. I can only hope that it is only this make-shift alternator and 'custom' placement that is causing belt damage. Either way, it will be replaced entirely to return to a known solution.

So I wanted to change my alternator belt, now I'm replacing everything that goes with. Gotta love that previous owner.

[PB Co]

Working on this now. I'm removing the over alternator and connector. What gets crimped to Hervey's D120?

[PB Co]

It all went back together just fine although looking back at the parts diagram I am now missing a single washer that does not effect spacing.

Thankfully half of the 'custom' tension arm was the original part and the bracket was still present on the block. The tension arm extension appears to have been added because the arm itself was bolted into the wrong location. It was bolted further down. What did I remove?

I connected the only wire from the new units connector to the brown/yellow of the original wiring as per the instructions. Battery output was checked and in the correct range as to not fry the regulator. The Special T D120 had another bolt with a connector/yellow crimp adapter I removed. My VIN puts me in the Duci range originally but there was nothing left to connect this last bit too.

At idle I'm just above the 13V mark with headlights on. The unit makes a slightly different sound than the old, just barely whining with a new belt. A happy ending, or total time bomb? Only drove it about five miles after the repair.