Correct Idle Pulley for OM647 Sprinter Engine

[Steady Eddie]

My first encounter- Service writer " Seems your top pulley is worn out, has no edges or groves." replaced with one that has edge and groves, also a little bit bigger. (wrong one for this engine)

If you are having- tensor failure, belts breaking, idle pulley failure, then check that top right pulley by the power streering pump. It should not have groves or an edge to it. It is a smoth pulley designed to have the belt ride on top not under. Correct part number should be 68020888AA or 05080319AA. Cost more, but saves hundreds in the long run. Euro parts sales the wrong one with their kit. Even the parts list at Dodge has the wrong one listed, it shows the same pullies for both locations. I did see a differance on the stress on my belt tensor with the big pulley, not so much with the correct one.

The OM647 engine mostly came in years 2004, 2005 and 2006.

 

[Steady Eddie]

This is the correct pulley. Those are not grooves just shined up from the belt ribs.

 

[tbcabs]

Thanks for the info. Was told by the dealer that the pulley i had on there was worn out

 

[Turtle]

Oh, Lord. Yeah, this is basic info (long ago discussed and detailed by Doktor A on the Sprinter forum). If a Sprinter technician or a service writer tells you that the pulley is supposed to have grooves, and that the groves and/or the shoulder edges have "worn out", just slap them upside the head with a serpentine belt, tell them thanks but no thanks, that you'll have it worked on at a place where they actually know something about Sprinters. It's kind of understandable, sort of, since Europarts sells the wrong pulley, (because) and the exploded parts catalog is actually incorrect and still shows the parts and diagram for the older 612 engine. But, if you stop and think about it, have you ever seen a ribbed belt wear down a grooved pulley smooth? Not gonna happen. The pulley had to have been smooth to start with.

This is just one of the many, many instances where you learn that with a Sprinter, "common sense" doesn't apply, like the common sense of the belt ribs should be running over pulley grooves, and not over a flat pulley. But on a Sprinter, flat pulley it is, because it's not designed to guide the belt, it's designed to be an anti-flutter pulley, primarily to deal with the decoupler pulley of the alternator. The grooved pulley (for the 612 engine) is about 5mm larger in diameter than the smooth pulley, which doesn't sound like a lot, but that 5mm difference can make all the difference in the world with added tension created with the decoupler pulley and can result in thrown or shredded belts when the belt slaps back onto the tops of the grooves instead of a flat surface.

I jut had mine replaced, and the correct part number shown on the invoice is 05080319AA. It is not listed in the 06 Exploded Parts Catalog, though it is listed (albeit misidentified) in the 05 Catalog. It's $50.10 from Berry Dodge ($76.56 List). The MB part number is 000 202 04 19.

(68020888AA is $32.40 from Berry, but it's a different pulley).

 

[OntarioVanMan]

Wonder how many went out and popped their hood to check?..

 

[Steady Eddie]

Oh, Lord. Yeah, this is basic info (long ago discussed and detailed by Doktor A on the Sprinter forum).

Yeah, I know, but this is not the Sprinter fourm and I thought for those that didn't know should. And those that know should be reminded as I see the large grooved pulley still on their Sprinters.

 

[scottm4211]

Thanks Eddie

 

[Turtle]

Yep, excellent post. Thanks to the error in the parts catalog and the service manual, and the way Berry Dodge sells 'em, lots of people end up running with the wrong pulley.

Of course, I've always had the correct pulley on mine, which doesn't explain why I go through belts and tensioners the way some people go through underwear.

 

[Steady Eddie]

Yep, excellent post. Thanks to the error in the parts catalog and the service manual, and the way Berry Dodge sells 'em, lots of people end up running with the wrong pulley.

Of course, I've always had the correct pulley on mine, which doesn't explain why I go through belts and tensioners the way some people go through underwear.

I was going through those, (not the underware), for a while, sometimes twice or three times a year. My problem was my alt was to small for what I wanted it to do. I only had a 90 amp, and was charging two aux batteries with a small cable. Changed to a 150 amp, much bigger cable, and the smart solenoid, that you use to have and so far no failure. Did your problem start when you changed from the "Smart Solenoid" to what you have now? Mine was failing when running and the refigerator would come on and draw to much, causing the alt clutch to drag, and this caused the belt to slip until about 1/4 inch of the belt would split and get wrapped around the fan taking wires, transmission coolant lines, blades from the fan, pullies, and one time the oil dip stick.

 

[Turtle]

Actually, most of my shredded belts happened with the solenoid. Since then, it's been mostly failed tensioners and thrown belts. Those alternators are designed to produce nearly twice their rated output, for that very reason of lagging clutches. It's kind of like the surge on an inverter. On an alternator, the rated output is the continuous output, before it starts frying itself, but it'll put out considerably more for short periods of time (an hour or two) before it scales itself back to rated output.

 

[Steady Eddie]

Actually, most of my shredded belts happened with the solenoid. Since then, it's been mostly failed tensioners and thrown belts. Those alternators are designed to produce nearly twice their rated output, for that very reason of lagging clutches. It's kind of like the surge on an inverter. On an alternator, the rated output is the continuous output, before it starts frying itself, but it'll put out considerably more for short periods of time (an hour or two) before it scales itself back to rated output.

Are the bolt holes to the tensioner wore out, or repaired at some point? If so, then that could cause the tensioner to wobble just enough to throw your belt. I went nuts trying to find out what mine was doing. Even throught the power steering pump could be bad, locking up and burning the belt into. Good luck trying to find out.