Alternator Turbo Resonator Change OM647

220629

Well-known member
My Experience Changing My 2004 OM647 Alternator

Search: Change, install, replace, renew, repair alternator and turbo resonator

I figured I'd write this up even though it has been covered already. It’s pretty basic stuff, but knowing what tools you’ll need may have some value.

Here's the short version so you can avoid my long descriptions. The turbo resonator stuff doesn’t apply to 2001 – 2003 OM612 engines.

Disconnect battery negative.
Remove tension on serpentine belt.
Remove turbo shield on top of engine for Turbo Resonator access.
Disconnect small terminal and large terminal on alternator.
Remove turbo resonator.
Remove alternator.
Reverse procedure to install with "Vee" notch to engine. Refer to post #9.

Easy as pie so even Orion would like it.

The Long Story

At our first fuel stop towing our boat down to New Orleans from Niagara Falls I needed to accelerate a bit more than I usually do into traffic and noticed a couple little chirps. I figured it was the alternator pulley. If I stayed easy on the throttle it seemed fine. Whenever we stopped for fuel I'd inspect the belt and see if the belt was wobbly. After shutdown I'd feel the belt to see if it was getting hot. It all worked fine the rest of the way to New Orleans, back, and then even a bit more driving once home. Easy on the throttle seemed to work just fine. The 90 amp clutch seemed OK by hand, but I don't really have experience to draw upon. With over 225,000 miles I figured changing the alternator was inevitable anyway.

Edit: The "chirping" was actually traced to an exhaust manifold leak. The old alternator is fine.

I upgraded to a 150 amp Bosch alternator from the originally ordered 90 amp (I'm removing the OEM?). The T1N alternators are all interchangeable 90, 120, up to 150 amp to the best of my knowledge (built in voltage regulator). The 150 amp unit is physically larger and took a bit more fiddling to get up into place.

I had a spare Turbo Resonator on hand. Since I needed to remove the TR to install the alternator I installed my Q5 spare. I recommend removing the TR for alternator access. It didn't look to me like I could have removed the one upper bolt without doing that. It made access much better. I also recommend changing out your TR if you aren't certain whether you have the newer Q5 style. It's only about $40 or $50 and would be a pain to change on the road.

Tools that I Needed

17 mm wrench with cord and hook for tensioner
Flashlight
Hose removal tools
3/8” 12 point box/open end wrench for alternator star head bolts (E torx E12?)
¼” 12 point for Turbo Resonator star head bolts (E Torx E7, possibly E8)
12 mm +/- box wrench for torque multiplier
13 mm box wrench for alt terminal
Straight screwdriver
8 mm box wrench for alt terminal and hose clamps
8 mm socket
3/8” ratchet with 3” extension
3/8” 12 point socket
10 mm socket
10 mm box open end wrench for battery negative (not shown)

Parts

Bosch alternator
6 rib PK2260 Serpentine Belt (Should be correct for NAS 2004 - 2006.)

Serpentine Belt Kit if needed. http://europarts-sd.com/mfg-subcat-item.asp?cID=102&scID=174


I normally prefer 6 point sockets so digging up my seldom used 3/8" 12 points for the star fasteners took some looking.

AlternatorTools.jpg

How I Did It

Disconnect the battery negative. (Have your OEM radio code in hand before doing this if applicable.)

Remove tension on the serpentine belt tensioner. I use a 12 point 17 mm box wrench tied back to a hook in the frame hole. There is a hole for a pin keeper in the tensioner to use to hold to it back if you prefer. Check the tensioner for smooth movement while you are there. Replace if it doesn't move smoothly. Mine seemed fine. Use this opportunity to check all the pulleys for smooth operation once the belt is loose.

Remove the Turbo Resonator

From above remove the turbo heat shield on the engine. A 10 mm socket works. The air filter hose removes easily and swings out of the way. It is not necessary to remove it, but it helps with TR access quite a bit. (OM612 owners can ignore this TR stuff..)

Loosen the hose clamp on the turbo resonator hose and clear it.

Back underneath use a ¼” 12 point box wrench to remove the top TR bolt first. That way the lower one holds the original position and keeps the upper bolt from binding. My upper bolt was so tight I needed to use a 12 mm box wrench added to the ¼” one to gain leverage. The torque increaser method is shown in the tool picture. After the TR is loose from the bracket go back up top and remove it.

Disconnect Electrical and Remove Alternator (Battery Negative Removed Previously)

Back underneath. Remove the electrical lugs. 8mm and 13mm nuts on those. If the nuts are tight you may need to hold the electrical lug with pliers so the stud doesn't twist in the plastic.

Use a 3/8” 12 point socket or box wrench to remove the lower alternator E Torx bolt which holds the TR bracket. Leave the other bolt alone so it holds position to prevent binding while you remove the upper bolts.

For the upper bolts remove the one with the TR bracket first. That way the bracket can be swung out of the way. I found the one upper bolt a real pain for access lying on my back. I’m certain a lift would make it easier.

*****
Added:
I don't recall this on the 2004. The 2006 upper *non-bracket* bolt wouldn't pull out for enough for removing. It hit a bracket which stopped the travel. I left the loose bolt in the hole. After the old alternator was out I set the alternators next to each other and transferred the bolt over to the new unit. The method has the additional advantage that it keeps the "Vee" notch in proper orientation.
*****

Remove the lower bolt and juggle the alternator down and out.

Re-install

Juggle the new alternator up into position with "Vee" notch toward engine.
20120528 edit: The alternator can be installed incorrectly so be careful. Thanks goes to Grey man 64 and Skydiver007 for the tips.
I finally had some spare time to take off the 120 amp alternator and spin it 180 degrees and it fits like a glove. The "V-notch" side is the one that mounts to the engine block side. Now it makes me wish I had kept the 150 amp alternator. You know what they say about hind sight...
A picture of my 150 amp installed is in post #9 further on.


Note: I installed the lower TR bracket bolt first without the bracket (the bracket gets in the way) and the other bolt with the hose support and snugged them up first before messing with the upper bolts. That sets the alignment. Install the one upper bolt and snug it up. Next remove the lower TR bracket bolt, then install the TR bracket with upper and lower bolts. Tighten all four bolts to spec.

Install the two alternator electrical lugs. Position the belt back over the pulley.

Back up above, clean and lube the turbo inlet bore. Install the new TR. Inspect that the belt is properly aligned to all the pulleys from above.

Back down underneath install the TR bracket bolts. Re-tension the serpentine belt.

Back up above connect the TR hose. Re-install the air filter hose if it was removed. Re-install the turbo heat shield.

Check to make certain no electrical connectors or hoses in the area of your work were knocked loose during the job. (MAF, Temperature sensor on air filter, etc.)

Double check that everything is completed. Connect the battery negative.

Good luck. vic

P.S. - I forgot to add that all fasteners should be greased or anti sieze applied for the next time.

Added:
Arnie Oli gives instructions on Regulator Change
https://sprinter-source.com/forums/showthread.php?p=563309#post563309

Got her out. Not much more life left in the brushes anyway. About twenty mins fudging around underneath keeping the alternator in situ and removing the regulator from underneath while my feet burn in the roaring sunshine.

Obviously disconnect battery...

Much easier if you use an E12 torx socket to move the supporting bracket for the turbo to one side.

Remove the bolts and screws shown, cover from alternator comes off and two needlessly hidden screws (WTF Bosch!) come out and the regulator slides out.
...
The pictures may go away. They aren't attached to Sprinter-source.
 
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jmoller99

Own a DAD ODB2 Unit.
This write up was just what I needed. About 1 1/2 hours to swap the alternator on my 2002.

The 13mm nut on the alternator wiring harness needs to be loosened up before removing the last 2 bolts holding the alternator in. Its on very tight. I also used sand paper to clean the 2 connections before putting the 13mm and 8mm nuts back on.

The alternator clutch on my 90 amp (9 years old - 175,000 miles) does not move at all like the new one does - its mostly locked up. I probably avoided having my fan belt shredded by changing this out.
 

Attachments

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Grey man 64

New member
Aqua Puttana,
Great write up. This was exactly what I needed when I replaced my alternator. I ran into a clearance issue when trying to install the 120 amp or 150 amp alternators. The alternator upper mounting and engine block mounting is gapped, +/-1/8" on the 120 amp and +/-1/4" on the 150 amp unit. Is there a shim package that should be used when upgrading from 90 amp to 120 or 150 amp alternators? Both alternator housings are up against the engine block and it seems that not only can the upper bolts not be tightened correctly, but the alternator housing can be cracked or damaged by engine vibration.

Any thoughts, experiences or solutions would be greatly appreciated.

Best regards,
Grey man 64
 

220629

Well-known member
First let me extend you a hale and hearty welcome to the forum. welcome2.gif

Aqua Puttana,
Great write up.
Thanks.
I ran into a clearance issue when trying to install the 120 amp or 150 amp alternators. ...
Did you replace with a Bosch 150 amp? I found that my 150 amp Bosch replacement needed more juggling around than the 90 amp OEM to R&R, but after it was up in place the 150 amp bolted right in.

There are no shim kits or other adapting which I have heard about related to Bosch alternators. Good luck. vic
 

sailquik

Well-known member
Old Crows,
I think pretty much all Sprinters have an alternator clutch.
The rotor inside the alternator has alot of mass, and it turns quite
fast.
It has an "over running clutch" so the alernator is free to continue to spin and
not eat holes in the serpentine belt when the engine slows rapidly.
Mostly the clutch causes no problems for the life of the alternator, but
there have been a few that failed.
Part of this equation is the serpentine belt tensioner I would hazard a guess.
The tensioner would not like being loaded the wrong way too many times.
Hope this helps,
Roger
 
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skydiver007

DRB III Owner If You Need
I have the answer for you as I have already done this a couple of times. The 150 amp will fit any Sprinter. It is thinner on one side than the other. If you get it up to the mounting holes and it wont fit, you have it backwards. Flip it around and it will work. Also eliminating the turbo resonator which leaks oil on it all the time will help extend its life.

The clutch in mine went bad and the whole bearing died. It was wierd, it would run fine up to 70mph then the charge light would come on. If I slowed down, charge light would go off. Took it off and the bearing was destroyed.

Also was a NAPA special which I will never buy again. Buy from Euro Parts SD.

Also careful tightening sense wire as the bolt will break very easily.
 

Grey man 64

New member
Did you replace with a Bosch 150 amp?

I bought a Durolast 120 amp alternator from Autozone. That could be the problem - variances in manufacturing process and tolerance. It's in there and working, but I'm not thrilled about the housing being up against the engine block. I bought some GM shims and will loosen the 4 bolts, slide the shims between the mounting points and block, and take up the difference between the block mounts and alternator mounts. I don't think that 1/8" will cause a problem with belt tension. I want to ensure of a solid mount but also have clearance between the alternator and block.

Or, as Skydiver007 pointed out, it could be oriented the wrong way. I took off the 90 amp unit and installed the 120 amp unit exactly the same way. However, the 90 amp unit had been replaced a year and two months ago (only had a one year warranty). Perhaps it was installed incorrectly as well and I just compounded my problem.
 
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220629

Well-known member
...Also eliminating the turbo resonator which leaks oil on it all the time will help extend its life.

...
I haven't noticed any oil leakage from my TR.

...
Or, as Skydiver007 pointed out, it could be oriented the wrong way.

...
I should think that the electrical connection location would dictate the orientation, but if there is enough slack ... :idunno:

As to shims, there must be enough takeup in the tensioner for a slight difference. Just be certain what you do doesn't affect the pulley/belt alignnments. Rotating the position may be the better solution.
No! It matters!!! The Vee notch position is the clue for proper orientation.

This is my 150 amp Bosch looking up. (Also note the position of the Field Connection - smaller wire being easily visible.)

150AmpAltVee.jpg


Good luck. vic

Edit. From a recent post/thread. Thanks goes to Andy. :thumbup:

The asymmetric (to shaft center axis) mounting flanges of the '02-'06 Sprinter's alternator means installation needs to be done with care and knowledge.

The 90A alternator can be installed 'backwards' without damage to alternator but D+ wire may not reach the inverted terminal easily.

The larger diameter 150A alternator will have interference issues if mounted backwards as you discovered.

I have also seen improperly stored salvage yard engines suffer alternator seizure due to corrosion and prevent minimum starter motor speeds for start to occur.

Doktor A
 
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skydiver007

DRB III Owner If You Need
When you buy this alternator. The Bosch 150 amp is used on more than one vehicle.

I read somewhere that you may have to remove the bolts and spin the back of the alternator around to align the connections to match the one you removed.

The 2 I installed both had to have this done. Including the one I bought from Euro Parts SD

If you bought a Sprinter 150amp alternator, it will fit, if not it is the wrong model.
 

skydiver007

DRB III Owner If You Need
I haven't noticed any oil leakage from my TR.


I should think that the electrical connection location would dictate the orientation, but if there is enough slack ... :idunno:

As to shims, there must be enough takeup in the tensioner for a slight difference. Just be certain what you do doesn't affect the pulley/belt alignnments. Changing the position may be the better solution.

This is my 150 amp Bosch looking up.

View attachment 43094



Good luck. vic

Even with a new resonator mine had oil in this area. I am not saying to go out and buy one, but the area where the alternator is mounted on most Sprinters is the worse area it could be with all the heat provided by the turbo.


If you look at the picture Vic supplied you can see that one side of the alternator is fatter on one side of the mounting screws than on the other side. The skinny side goes against the engine.
Anything you can do to keep heat and liquid away from an alternator is a good idea.
 
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Grey man 64

New member
I finally had some spare time to take off the 120 amp alternator and spin it 180 degrees and it fits like a glove. The "V-notch" side is the one that mounts to the engine block side. Now it makes me wish I had kept the 150 amp alternator. You know what they say about hind sight...
 

skydiver007

DRB III Owner If You Need
It was 20 below in February in a very little town in North Dakota the last time mine got changed and I helped the mechanic install it in his semi-warm garage. He mounted it backwards the first time too. I had forgot about the V notch facing the engine. Good Stuff.
 

amrbackup

New member
My Experience Changing My 2004 OM647 Alternator

Remove tension on the serpentine belt tensioner. I use a 12 point 17 mm box wrench tied back to a hook in the frame hole. There is a hole for a pin keeper in the tensioner to use to hold to it back if you prefer. Check the tensioner for smooth movement while you are there. Replace if it doesn't move smoothly. Mine seemed fine. Use this opportunity to check all the pulleys for smooth operation once the belt is loose.
Something I found handy to do if I could add a small note to this procedure is to remove the airconditioner Idler/belt tensioner pulley and arm completly, it was in my way of pushing the wrench over to remove the tension from the main belt. After I removed the tension and slipped the belt off of the alternator pulley wheel I did not wire the wrench to the frame, I just let it relax against the pulley wheel on the engine, there's not enough tension that it's going to damage anything, but it had enough tension that it would hold the wrench to the tensioner and not fall off. I think it's a dream world to think that a pin could be slipped into the proper space to hold the tensioner back, I just did not have the room to get my hand up there.

I recently went through your procedure to replace my alternator that was not working, it made some growling noises for about 2 days, then it stopped charging the battery at all. When my battery voltage got down below 9 volts all of my dash lights were on and the van ran really rough in shifting gears. At 6 volts the dash lights just went off completly.

After finding the price difference in a new alternator at $1832.00 at a local Dodge dealer In Calgary(but they could get me an aftermarket one from Napa at $560) I went to the Napa directly and found their price to be $360 for a 3 year warranty, or $475 for an unlimited lifetime warranty, to the Parts source at $315. I called some alternator rebuilders and one would do it in about 1.5 hours, for $145. I figured that even if I had problems I could get it done twice for the same cost as doing it once from the auto parts suppliers.

I was surprised at the price difference, Shocked at what a dealer would charge, even after looking on ebay, and some of the links that people posted(great resources!) I was still looking at around $300 to get the alternator and have it shipped. Time was of the essence so being able to take it into the rebuilders office on a Saturday and have it back in 1.5 hours was a great service, the one I got back was not my original frame, but I don't care, this one was nice and new looking and my old one was an aftermarket one anyway. New one had new bearings, clutch/pulley wheel, brushes and Diode pack. Time will tell if the rebuilder did a good job.
Thanks to all who contributed to this post, I really appreciate the resources that this group offers, it gave me the courage/knowledge to try and swap the alternator out, I saved the 75$ charge that the rebuilder would have charged to do it for me.
 
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skydiver007

DRB III Owner If You Need
A common mistake is to mount the alternator with the fat side toward the engine block. If you look at your photos, you will see that there is a "V" groove in the middle of the bracket holes. Mount these to the engine block side and you will be fine and not have to remove it and do it again. Also disconnect the battery as you will blow a 200amp fuse under the hood if the alternator wire shorts against anything.
 

Harold Ross

New member
Thanks for a great write-up, Aqua Puttana. I used it every step of the way, and it was just detailed enough.:thumbup:
Bought the 150 Bosch from Europarts SD, along with the resonator eliminator, and new belt.
Recieved the alternator in less than 48 hours, from Europarts to Pennsylvania!
This was a huge help!:bow::cheers:
 

flan8tive

New member
This is a great write up and an excellent tool list. Just pulled my old 90A and installed a new Bosch 150A I just got on Amazon for about $185. Incredible deal, I was dubious it would fit, but it bolted up perfectly.

The old 90A clutch was making a bit of a clack-clack-clack racket.

I would only mention that when installing the 150A remove the lower turbo bracket bolt, then crack open the 13mm at the top of this bracket (right under the turbo) so the bracket swings away. With this piece out of the way it makes for a huge amount of swing room when tipping the larger alternator up into position. When re-installing, thread the bottom turbo bracket bolt hand tight then tighten the top.

Has anyone been able to shoehorn a 150A into position without doing this? I can't see how it is possible, but this was only install #1 for me.
 

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