I swear this engine I'm dealing with is just cursed to not run right. I only get to drive this thing 50-100 miles at a time before something else breaks.

Anyway, the latest problem I've come across is the fan pulley rubbing against the harmonic balancer. I've never seen this happen in any of the M103s I've owned before. After I replaced the belt and sanded down the fan pulley due to some noises I heard, I drove the car to work today and on the way home I started hearing some scratching noises coming from the engine. When I parked the car in the garage I saw this:



The harmonic balancer is making contact with the fan pulley. I also noticed that the edge of my belt is not lined up with the inside of the fan pulley, like the fan pulley stretched out over the weekend while I was driving or something:



I ran the engine while watching this little area and both the harmonic balancer and fan pulley look to be spinning true, nothing is bent out of shape, but they are interfering with each other.

The harmonic balancer lines up with the front crank position sensor like this illustration for the M104. So I don't think the harmonic balancer is falling off the hub.


The fan clutch bearing bracket is brand new and has seen less than 500 miles so I don't really think it's the bearing. I remember checking last Saturday when I replaced the belt and sanded down the fan pulley to remove glazing from the flat surface.

Any ideas for reasons why this is happening before I go blindly replacing the pulley?

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Are the fan pulley to fan bearing bolts tight? Was the pulley fully on the fan bracket hub before tightening the bolts? ( Like installing a wheel )

I did tighten the pulley to the bearing correctly.

I went back through my orders and EPC to confirm the part number and I may have found a source of error. I haven't confirmed this yet, but I may have installed the wrong fan bearing bracket

M104.980 calls for part 104 200 05 28. I have a 95 E320 with the M104.992 that needed a new fan bearing bracket as well and I ordered it's part 104 200 13 28. I ordered both online at different times and labeled their boxes which one goes to which car, but there is a possibility for a mismatch either on my part installing the wrong one or the retailer sending me the wrong part.

I hope there's a part number stamped somewhere on the metal I can reference to see which part I installed for which car.

Update: So I did install the correct part. There is a Febi part number of 11949 stamped near the idle pulley and that part number cross references to 104 200 05 28 which is correct. I don't really know what else to say or do besides install the new pulley and hope for the best. There is very tight space clearance between the harmonic balancer and the fan pulley.

The spacer/washer is supposed to go on the front correct? Not on the bearing hub? The pulley itself only goes on one way since installing it backwards shows me that the belt is totally out of alignment.

The harmonic balancer is sitting flush against the sealing surface of the front crank seal, so it's not falling forwards.




Edit: OK what I've decided to do is install 2 of those spacers, one on the front and one on the rear. I have a spare M103 motor that I took the washer from and installed it on the inside. The old and new pulley both cleared without interference since the engine is cold, but the tight clearance to the harmonic balancer made me uncomfortable. I couldn't even slide a credit card between the two parts! Now, with the spacer between the bearing hub and pulley, there is maybe 2 or 3 mm of clearance between the harmonic balancer and the fan pulley. Additionally, the belt now rides perfectly in the middle of the fan pulley rather than favoring the radiator side of the pulley as I pictured in the original post.

I have a feeling the fan bearing clutch is defective/out of spec so the pulley sits a little closer to the engine, but I'm not in the mood to send it back for a refund right now. Another theory is that the part number 104 200 05 28 is meant for the newer style harmonic balancer/crank pulley since I did see that 104 200 05 28 superceded an older part number. Maybe someone just goofed in EPC for the M104.980s and forgot to do an As of/Up to engine serial number thing.

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Did the fan pulley get flipped over during install? From the pics it looks like flipping it over would give more clearance.

Flipping the fan pulley the other way would give more clearance, but it also makes the belt run completely off alignment by about a full inch. I installed it with the pulley part number facing the radiator.

Johns the part you have may be wrong . Get your old one you removed ? take a look at both pulleys together one must be wrong . If both are the same then bracket part is wrong

John you need to put more information on your profile .
I would need to back track on the part you purchased
Need the model year and when it was made i think its a W124 with the m104 engine and need the engine size
Most brackets i can find are 104 200 1328 .

I find John that the febi number for your engine M104 980- 2.8 W124 part number is 050401. Check it on ebay like i did search your bracket look at the numbers after .

Hey optimusprime,

The information you're looking for is 1991 300CE with the 3.0L-24v M104 engine. 104 200 13 28 part number is used on the later 3.2L M104 motors which is what I thought I accidentally installed since I was working on a 95 E320 during the same week doing the same repair job. I had correctly installed part number 104 200 05 28 after confirming the Febi stamped number 11949 when I took the fan pulley off to examine it.

Right now I'm attributing the failure to a bad aftermarket part. Even though it is Febi it's still not an OE dealer part. The bearing hub is either pressed too far onto the shaft or it is too small so the pulley sits too close to the engine.

You might be right dont know really ,as i thought it was a 2.8 M104 .thats the Febi number for it But now i see your talking about another bracket . 300ce i took a shot withe the W124 model. See what i can find for the 24 valve M104 now

JOHN I find this after 2 hours searching its not a very easy part to find .
You need to check it your self with the Ebay site in the uk item number is for the Febi fan clutch bearing bracket , number for it is 10117-26380 NF . The ebay item number is - 272484263635 seller is partsnavigator part for 1991 300ce 24 valve [C124-061 ] i think these are the numbers of the first 6 figs of your vin numbers. Just check the list of cars it fits in the ebay list bellow . This is just to double check you have the right bracket or not .

I looked into that Febi part 10117 and it looks like it cross references to 103 200 17 28 which brings up a completely new option that wasn't available to me when I was searching in the EPC by VIN:



I'll check this part out if I ever have to replace my fan bearing bracket again. But for now, spacing the pulley out seems to be working just fine. I've driven around 80 miles since that little modification and nothing has broken yet.

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Based on what the EPC shows, it looks like you have the correct bearing bracket. All US cars have a catalyst, the other part number shows it is only for cars without catalyst.

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You could always put some spacers ( flat washers ) under the bracket to space it out.