Bearings! Wheels and Idlers go round & round.

Problem is, they're making a sound.


With too much snow and cold to do much else, I decide to find out why my front left wheel was so grindy sounding. Steering was not impaired, and the wheel didn't feel loose, but man, did I get a rrrrrrrrrrr sound from what had been quiet tires.

So, take off the wheels.



You smart readers will notice that's the right side wheel, but I figured, why not do both while its on the lift, and I'm in the groove.

Germans being Germans, I see that a mere cotter pin in not good (or expensive) enough for holding everything together. The fancy locking 'nut' sure is slick.

Also a great time to check brake pads, clean up the calipers, lube them with brake 'grease' as necessary.

You get the pleasure of beating the rotor off the hub assembly. Since the rotor is still OK, I used pbBlaster and Mopar Rust Spray (DrA's EGR cleaner) to loosen some rust overnight on the hub area. Plastic mallet to 'work' around the rotor, not beating it to death with a sledge.

Remove the calipers from the caliper brackets- be careful with the pad sensor- and hang the caliper by wire from the strut.



You can tell I'm a bit paranoid, and don't relish replacing brake lines and bleeding brakes, so added a secondary support for the caliper. Whatever.....

A bearing diagnosis trick is to rotate the hub / wheel while holding on to the suspension spring- grinding will be amplified. With no spring, I held on the strut bottom and felt some grinding while spinning.

After pulling the hub and cursing the seal out, I sensed a severe grinding in the big inside bearing. At 287XXX miles, I decided bearing are cheap, didn't even bother trying to clean the old bearings. Grease looked a bit old and sparse as well.

I went to my friendly local NAPA store and had these the next day:



Quality SKF bearings, not from China.

So I also get the pleasure of removing the old races and cursing in the new races! yay!

Heat (grow) the hubs in my ShopOven



Shrink the races in the outdoors freezer



Then proceed to install the races using welders gloves, appropriate sized sockets and a hammer. And wish I had a real bearing driver for the big race. Eventually I found a 2 ?/8 socket which fit the big amazingly well. However, that one had to be driven in more, as the cold race quickly heated up from the hub. Small side slipped right in.

I didn't take pics of greasing the bearings, not much to see, other than working grease into the interior of the bearing. Smash it in there good, grease is life. From the side, top and bottom- push it, rotate the bearing, get it in there. Big bearing goes in the hub, then the seal is put back in, using the appropriate seal driver, or a very large socket and a mallet.

Hub back on, tighten the fancy retainer nut according to the manual. Since I can't measure .02-.04mm play like the book says, I used the typical tighten and back it off procedure. The flat square washer slides a bit behind the tightened nut. (PS- use your head. I'm not responsible for your wheel falling off. If you don't know what you're doing, hire someone that DOES. Yes- this nut holds on your wheel. Wheels are important at speeds of 10mph or more. REALLY. You mean you're getting mechanical advice off the internet?)

Reassemble the calipers and rotors again per the instructions, and we're ready for the next project. Which was spraying some undercoating on the wheel wheels to help dampen the noise of the next dying wheel bearing. Oh, and doing the other side, which was not at all grindy. Those bearings just got a thorough cleaning, fresh grease and a new seal.

While we're talking bearings, why is all that racket coming from the engine compartment while the engine is running?

Hmmmmmmmmmmmmm.

See that round thing to your left of the fan/waterpump pulley? That's an idler.



Here's its twin, on the other side




Those little guys can cause all manner of problem, like thrown or torn up belts. I might as well do an inspection. And check on the tensioner. I didn't take pics of how I did tho- its a bit tight in there! Check your manual- you can untension the tensioner with an 11/16 socket on a longer breaker bar or ratchet, then pin it in place with a punch or small phillips screwdriver. But you don't have a lot of room to work with because of the intercooler and rad. It is much easier to do this from underneath the vehicle.

Be sure to diagram your belt before undoing it!

Un do the belt and check it for fraying, cracks, tears, etc. Mine looked fine. Great!

Then spin the idlers. You want a quiet, dead, but free spin, much like the bearings are gooped up with grease. You don't want any wobble or a zzzzzzzzzzzzzing! free spin, with noise, like the wheels on your old pinewood derby car. That means there's no grease in the bearings.

This is also a good time to check the alternator. Spins freely? No grindy noises? great!

Taking off the idlers is a bit of fun. You need a T50 torx driver- the best might be like a bent allen wrench, but you can do it with a socket/ratchet type - but it won't be fun. Pop the plastic cap off with a screwdriver or pick. Watch the driver side idler- there is a little bobbin or spacer underneath it. Don't lose it!

I bought my replacements at NAPA - they were in stock! Look below, they appear basically identical, except the bearing is larger. Also, the little cap will not fit back on. I don't really see much purpose to it, other than keep crap out of the Torx sockethead.

MB part on the left, NAPA (Gates brand) on the right





$36 each (wow- that hurt!) at your local NAPA store. I'll get the part number...

Thread 'em back on the engine, being sure to properly seat the head of the bolt in the bearing, and remember the spacer on the drivers side. Eyeball that the pulley line up properly with everything else, just to be sure.

Thread the belt back on, saving the A/C pulley for last - work the tensioner with one hand, slip the belt over the AC pulley with the other, release pulley, and you're good!

Start it back up... hear / see the results.

WOW! My engine is much quieter! Those little things made a bunch of racket. Plus, when I kick in the AC, I don't get the chirping noise anymore.

Not knowing when to leave good enough alone, I decide to check under the valve cover for black death.

When I bought the van I didn't check it, even though it only had 282XXX miles on it.

So, with a feeling of impending doom, I cracked the cover... and found... NOTHING.

Maybe a CC or 2 of goop that leaked around the front injector, but other than that, clean. Almost scary clean.

I can now sleep easily at night.

1cylshort said:

Maybe a CC or 2 of goop that leaked around the front injector, but other than that, clean.

Click to expand...

Like this? If yes, then you have the black death.

that area is all clean silver. Some very minute black, not even the size of the arrow head you've drawn.

If anything I can keep an eye on it, but nothing to panic about yet.

Since I still had the cover off, I figured I'd double check.

Well, I'm going to recant that statement about clean injectors. Found a stray piece of plastic in the injector well, blocking my view of the crud underneath it. With a little strategic photography, it looks like 1 & 2 will need some attention.

Bummer.

WayneRodd to the black courtesy phone...

Don't know what this is- not off the injector cover:



Number 1 injector (liquidy)



again:




Number 2: (kinda dry, cooked off)

Doesn't look like black death to me, looks more like oil from an oil leak at your blowby oil separator. Maybe the source of the plastic part you found?

talkinghorse43 said:

Doesn't look like black death to me, looks more like oil from an oil leak at your blowby oil separator. Maybe the source of the plastic part you found?

Click to expand...

Is that the round hockey puck like thing on the pass. side front of the engine, under the cover- with a breather hose going to the turbo? See bottom of first injector pic.

I looked at that, and it looks rather new and clean- and the mounting points are all there. I was wondering if maybe it had been replaced.

I wondered if the liquidy stuff was more like EGR puke, because I sure didn't remember seeing liquid there when I first inspected. However, I did run the engine with the cover off for just a short time, backing it out of the lift (and to enjoy the silence of my belt idlers)

1cylshort said:

Is that the round hockey puck like thing on the pass. side front of the engine, under the cover- with a breather hose going to the turbo? See bottom of first injector pic.

Click to expand...

Yes

I looked at that, and it looks rather new and clean- and the mounting points are all there. I was wondering if maybe it had been replaced.

Click to expand...

If new, then the oil could be from the original or from the changeout as oil has low vapor pressure and can stick around for a long time.

Cool. I'm quite fine if its not black death. Maybe its just a minor black cold. (I'm not dead yet!)

WayneRodd is fairly local to me, I've got a call into him, so I can get an eyeball-on-it opinion sometime.

I suppose I could clean up with some carbcleaner, and see if anything develops in the future.

After looking at the pics, Wayne called and told me it just looks like oil, not Black Death.

We also agreed not to clean it up with a solvent- which might wick down the injector and cause it to corrode and really seize.

So, back to worrying about other potential Sprinter problems!

When I first got my sprinter back in November, I was getting bearing squeak. checked all 4 wheels, found nothing. Then had my idler grenade on me about 60 miles south of Dallas on a sunday. Luckily it happened right across the interstate from a Petro station with a full shop. One of the mechanics took called around and found me the part. Hitchhiked 60 miles round trip to an Autozone in Waxahachie, where they had the part in stock! I now carry an extra idler in my tool box .

BigBassape,
Might be a good idea to stop at a Dodge or MB dealer and get the OEM Factory replacement part.
Several members here have had early failures with aftermarket or parts store branded "knock off"
idler pulley arms and pulleys.
Guess it depends of if you want to change the pulley/idler arm again somewhere out in the middle of
Texas on a Sunday afternoon.
May not be a Petro Station with a mechanic right across the street next time it fails.
Roger

I thought that the dispute was with the quality of the aftermarket belt tensioner assembly proper vs OEM? (For the record I'm not disagreeing with that one.)

I don't recall many posts about aftermarket idler pulley failures over OEM. The tensioner assembly sees some pretty great stresses. The idler or anti-flutter pulleys not so much. They are basically just a bearing with a plastic belt guide assembled around it.

My intention is not to start another flurry of "Only use OEM parts or you'll surely regret it" responses. Should you respond please refer to specific posts or other information.

FWIW. vic

Aqua Puttana said:

I thought that the dispute was with the quality of the aftermarket belt tensioner assembly proper vs OEM? (For the record I'm not disagreeing with that one.)

I don't recall many posts about aftermarket idler pulley failures over OEM. The tensioner assembly sees some pretty great stresses. The idler or anti-flutter pulleys not so much. They are basically just a bearing with a plastic belt guide assembled around it.

My intention is not to start another flurry of "Only use OEM parts or you'll surely regret it" responses. Should you respond please refer to specific posts or other information.

FWIW. vic

Click to expand...

Yeah, but you have accidentally pulled Roger up for writing idler where he meant tensioner , although like you I have no problem with using an aftermarket tensioner pulley on the original tensioner assembler (I have an aftermarket damper on mine too, just the arm, pivot, and spring are original). Not sure if that is possible on the cdi tensioners but looks like what Roger meant?

Boater said:

Yeah, but you have accidentally pulled Roger up for writing idler where he meant tensioner , although like you I have no problem with using an aftermarket tensioner pulley on the original tensioner assembler (I have an aftermarket damper on mine too, just the arm, pivot, and spring are original). Not sure if that is possible on the cdi tensioners but looks like what Roger meant?

Click to expand...

Maybe not accidentally? "Pulleys" is plural. vic

P.S. - If I remember correctly from pictures I've seen, your old T1N uses a stretch coil type spring to supply tension? Our NAFTA T1N idler assemblies use a wound spring which is built into the aluminum pivot assembly. I believe it is the aftermarket aluminum casting which fails under the stress, or from corrosion.

sailquik said:

BigBassape,
Might be a good idea to stop at a Dodge or MB dealer and get the OEM Factory replacement part.
Several members here have had early failures with aftermarket or parts store branded "knock off"
idler pulley arms and pulleys.
Guess it depends of if you want to change the pulley/idler arm again somewhere out in the middle of
Texas on a Sunday afternoon.
May not be a Petro Station with a mechanic right across the street next time it fails.
Roger

Click to expand...

Guys,
OK, it's probably the aftermarket tensioner that has the early failures if non- OEM are used, but for my money, I'll stick with the
genuine MB designed and manufactured/controlled parts unless, as the OP was, I'm in the middle of nowhere on a Sunday afternoon.
Then you use whatever you can get.
My point was more from the "bigger picture" concept that if you replace these sort of components with OEM you reduce the likelyhood
of early failures, and early failure of any of the serpentine pulley sheaves, the flat idler sheave, the tensioner assembly has the potential
to destroy a whole lot of other things (trans cooler lines, backside of the radiator, etc.) and just having the serpentine belt come off
has resulted in huge damages, in several cases, reported right here on this forum.
Roger

The NAPA source idler pulleys that I used are part number 38082.

They are made by Gates in Canada, and I believe Gates to know a few things about making belts. In addition, they use a larger bearing than the original MB part. I believe this to be a safe alternative that I can source from my local store.

I did not need to replace the tensioner, as that pulley bearing was fine. If I did, I would have used the MB / Dodge part, as the spring and casting durability is what appears to be so critical in that part.

For part number reference, the front wheel bearings I used were BR35 (large inside- Germany) and 33205J (small outside - Mexico), and the seal was 21550 (from Hungary). All were NAPA sourced SKF brand bearings.

Again, if you choose to do this project yourself, please remember that you are dealing with absolutely safety-critical aspects of your vehicle. You should read the official service manual, know what you're doing, and if you don't - please know enough to consult or hire someone who does know what they are doing.