Steve's alt-belt/pulley modification

[rackley]

Steve, can you elaborate on your alternator belt/pulley modification?  I neutered my AC a while ago and I'd love to get rid of the compressor.  It causes so many belt problems it's nuts.

[srivett]

When I purchased this car it had power steering and all of the AC system except for the compressor.  The mech put on a used pulley.  Shortly after I had the power steering pump blow up and I was going through alternator belts every 20K km.  Since then I removed the rest of the AC (rad, hoses, evaporator fittings, etc.) and tried a 2nd used pulley.

Here are some photos and a video with my belt out of alignment.  I took my alternator to a wrecker and the kid who swapped pulleys for me did not replace a spacer.

The belt is a 13x1170.  To adjust the alternator tension you push the alternator towards the engine.  Below the alternator is an engine heater that I rarely need to use.  To the side is some generic intake hose that rubs through the coolant hose below it.  The upper rad hose has that bit of padding to keep it from wearing through against the alternator.  The last two pictures are of me checking the alignment with a piece of 1/4" square cold rolled steel.  As you can see the belt really flaps around.  It's not nearly as bad once the 3 minute glowplug timer shuts off  but it is still a problem.

Steve

http://chat.carleton.ca/~srivett/IMG_0807.jpg
http://chat.carleton.ca/~srivett/IMG_0808.jpg
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http://chat.carleton.ca/~srivett/belt.avi

[rackley]

Nice.  Did the car come with that alternator mounting arm with a slot or did you fab that somehow?  I have two engines and two of those arms and both of them only have a single bolt hole to hold the alternator.

[srivett]

Sorry, I don't know what that arm is off of.  It is held on by the same bolt that holds the engine lifting eye.  The shop that did the work specialized in European cars so I'm sure that's what it came off of.

Steve

[fatmobile]

I've had a few problems with AC pullys not lining up.
 Much of the time it's the bolt hole wearing into an oval shape, making the alternator lean toward the belt.
 I've taken a piece of 3/8" stainless, ground half of it off, pounded it around the long alternator bolt, then put the bolt into the hole. When I tighten down the bolt it presses the piece of stainless into the hole on the side that is worn. I pull the bolt out, use a rat tail file to remove the high spots so the bolt slides in and out nicely.
 This pulls the alternator back away from the belt.
 Grab your alternator, without a loose belt and see how much it moves toward and away from the belt.

[srivett]

I got my pulley today and things are looking pretty good.  The cost was only 10.60 CDN plus tax so I'm glad I bought two of them.  Now my belt runs smoothly during the 3 minute glowplug cycle and I can no longer smell burning rubber when I'm close to it.  I can probably get away with less belt tension too so that'll improve alternator life.  My idle is even a bit quieter.

In order to get the old pulley off I put a drift in the side of the alternator to jam the rotor against the housing.  Then I simply undid the nut.  After some checking alignment was possible by putting a regular washer between the alternator and solid alternator bracket (17 mm head bolt).  This washer was previously missing from my car as it was in my *very small* mystery pile of parts from the transmission swap.   :oops: I even noted that the sliding spacer was really out of position when installing my alternator previously.  Ah well, it was dark and I was covered in CV axle grease so wierd things can happen.    I did not use either of the two spacers supplied with the pulley but I did need a second washer under the pulley nut in order to snug things up.  Having the woodruff key that is supposed to be on the alternator shaft would have been nice but it isn't necessary.

Some numbers from the pulley are 43532, 0 120 489 381, 90-15-6141, 1-126-600-465  It's simply a single belt pulley for a non-ac 60 amp alternator.  No mods are required to put it on an ac 90 amp alternator.

Steve

[fspGTD]

Steve - wow that is a great price on an alt. pulley.

I found that old picture of when my alternator belt broke/jumped off the crank pulley, wrapped around the crank pulley and burned through the lower timing belt cover, and jammed itself inside there, which broke the timing belt and resulted in pistons hitting valves.  Warning: this is a painful sight!



Proper v-belt and pulley maintenance on these engines shouldn't just be nice to have, should be considered a "must" IMO.

[srivett]

The pulley is a Taiwanese aftermarket part I ordered from an alternator rebuild shop so that explains the price a little.  I thin I said it before, but VW Canada quoted me 70 to 120 CDN for a pulley depending on the amperage rating of the alternator.  I've run the thing for about 1000 km now and it's been making a faint turbo charger whine the whole time.  It is okay at idle but I can hear it when I'm running the car up in the RPMs with the windows down.  I'm hoping that it's just the used belt working in on the new pulley.  I'm really hoping it's not my timing belt falling apart...I am due to change it...I think.  I can't believe the mechanic didn't mark the car somewhere regarding the timing belt.  It should have 2 or 3 timing belt stickers on it somewhere but I have not seen them.   :?

IT IS REALLY WIERD HOW THE 13 MM BELT DOESN'T FIT FLUSH INTO THE STAMPED PULLEY'S  

Cheers, Steve

[fspGTD]

Steve - sounds like you need a file to keep track of the maintenance done to your car.

FYI, I looked up the v-belt specifications for a '92 Golf Diesel...

(optional) Power Steering belt: 9.5x740mm (connects crank, water pump, and PS pump)

(for cars without A/C) Alternator belt: 9.5x965mm (connects crank, water pump, and alternator)

(for cars with A/C):
  A/C belt: 12.5x947mm (connects crank, water pump, and A/C)
  Alternator Belt (connects A/C, alternator, and idler):
        12.5x947mm if no Power Steering,
        or 9.5x695mm if Power Steering equipped


Maybe you need an alternator pulley for vehicles with A/C and Power Steering, as it is designed to take a 12.5mm wide belt (versus all other configurations where it's only for 9.5mm wide belts.)

[srivett]

The supercharger noise has gone away now that the pulley/belt have bedded in.  I haven't had to adjust the belt in the last 3K km and it still doesn't smell like it is burning so I think I've won the battle.

fspGTD:  The counterfeit Bosch pulley I bought showed a belt size of 12.7 mm so it's pretty close to what I need.  The wierd thing with the non-AC cars is that the larger crank pulleys are still used.  It just doesn't look natural to have a 9.5 belt in such a deeps pulleys.

Steve