fan clutch bearing bracket noise - How long will it last?
 

My 300e started to make noise yesterday. Tracked it down to the fan clutch bearing bracket. Unfortuneately, I'm working about 250 miles from my tools (home) and won't be going there until Friday. The noise is very loud at start up, but then seems to almost go away shortly after warm up.

Does anyone have a guess (or any experience) on how long this might last?

How much driving between now and then?

You could be ok till after you go home or it could go anytime.

With the engine off can you wiggle the clutch back and forth?.. how much play?

I think mine squeeled for over a week before it went. Its the kind of thing where you can limp home to a degree.

I can't remember exactly but I think it was squeeling constantly when I broke it down... ie don't take off the belt until you are ready to fix it because the belt kind of holds it together... Also if you let it go a little the front half of the bearing bracket wil pull right out with the clutch and fan attached.

Only need to drive about 8 miles a day until Friday and then it's about 250 to get home. It does wiggle some. I think most of the noise is the plastic fan hitting a pully. This seems to quiet down quickly after about a minute of driving.

Good luck.

The pulley is probably rubbing against something on the front of the block near the bottom right (facing from front of car) of it's travel. You will perhaps need to replace the pulley as well by the time you get home. 250 + is not a short drive. Do you have an auto club membership? You might want to call some local salvage yards and see if anyone has a bearing bracket and pulley assembly near you. Paying a shop to do it might be cheaper than getting stranded on the interstate.

Made it home. The fan clutch bearing was shot. Replaced it yesterday. Only damage was a few nicks on the plastic fan blades which were hitting one of the pulleys.

good deal.

tom w

Fan Bearing Bracket
 

I sure am glad I read this old post, besides others of course, but yours is right on. And fortunately for me my parts are on the way should arrive Monday>tuesday lastest. Fast question was it an easy job for the DIY. I'm also reading up on it as well and have received phone contact with a forum member with verbal instructions

I just want to make sure I can handle the job, looks very straight forward. Thanks:deadhorse:

Its pretty straight forward. I replaced mine about 2 months ago, and it took about 2 hours. Did it working outside in the dark!


Just get the bolts back into their respective holes!

Ah- this happened to my on my 1991 Lexus LS400 and it went fast! Around 219K, I was setting in a drive-thru one night and all of a sudden it sounded like my engine was knocking! :eek: I pulled over and noticed that the pulley was wobbling. I thought it was the water pump, but later discovered that the fan runs on that bearing.

I drove the car home very slowly, sounding like it was going to fly apart any moment. I made it home, but was not wanting to attempt to drive it to the mechanics, so I had it trailered to the mechanic and had him put on a new one. Water pump and timing belt had only 23K on them, so we didnt replace those. $125 labor and $160 part, I was back on the road. :rolleyes:

Did mine recently, very easy job. Remove belt, fan clutch, smog pump, and then bearing comes out easily,,,

Piece of advice though...don't buy an aftermarket part because the fitment is junk, I bought a URO parts bearing bracket for cheap. it broke on me while installing the smog pump, as it would not fit.....

On a 91 330E, and probably other M103's, there is an O-ring that should be installed.

The Fan bearing bracket mounts to the upper timing cover. As you face the fan bearing bracket, the bottom right bolt (I believe it's the one that the bottom of the belt tensioner shock mounts to), goes through an enlarged hole in the timing cover. There may be a taper/chamfer at the opening on the t-cover and/or a step. This is where the O-ring goes (the bolt goes through it). At the MB parts counter this is called the "timing cover o-ring". I found that the O-ring didn't fit tight around the bolt at all and neither did it stick out past the t-cover surface far enough to make any kind of a seal. I read somewhere that you are supposed to use the black MB (or equivalent) sealant on the mating surfaces of the bracket and t-cover at that hole AND under the washer of the bolt on the outside as well. Failure to do this could result in an oil leak whose source is very hard to spot.