603 fanbelt removal clairfication question - PeachParts Mercedes-Benz Forum

JDmills · #1 06-01-2009, 06:54 AM

I am ready to try and replace a fanbelt, but am unsure how to remove the tension from the present one.. That is, I understand that the little black plastic jobber on the top of the head, which is attached to the spring, as well as the shock is involved..

and that needs to get turned clock wise to release tension on the belt?
Does the 10 mm bolt need to come out of that plastic block (i assume it does) what about the bolt at the top of the 13 mm shock?

I have read that some say this is farily easy to do, maybe I am just complicating it in my mind.

ashedd · #2 06-01-2009, 11:30 AM

I too was confused when I was reading about it. Once you do you will realize just how easy it is.

Yes the bolt comes out. You put something(3/8" extension) in the hole on the plastic thing. Take tension off the bolt so it will come out easy. Remove bolt then let the plastic thing rotate in whatever direction the spring wants to pull it. Give it a try and you will see just how easy it is.

compu_85 · #3 06-01-2009, 05:01 PM

2x The belt setup on the 60x engine is excellent, very easy to service. Plus it uses the same belt as a GM 3800 V6, so you can get a quality belt anywhere. Pay attention to the belt routing, it is possible to install it incorrectly.

-Jason

JDmills · #4 06-01-2009, 06:02 PM

Great, thanks for your encouragement. . . I will have at it tonight.

Brian Carlton · #5 06-01-2009, 06:36 PM

Quote:

Originally Posted by JDmills

Great, thanks for your encouragement. . . I will have at it tonight.

If you are changing the belt, you must pay attention to the installation of the new belt around the tensioner. The end of the belt will not pass through the crankshaft and water pump pulleys. You must install the end over the tensioner pulley first and slide the belt in sideways between these two larger pulleys..........then work the ends around in a large circle.

The belt can be changed in 10 minutes........or it can take 10 hours.

Report back if you get "jammed up"............

Hatterasguy · #6 06-01-2009, 06:45 PM

I found a 3/8 rachet extension to work perfectly to release the tension. Take the nut off the bolt that holds the plastic thing, and stick the extenstion into the hole on top. Take the pressure off the bolt and push it back.

Once you do it once, it makes perfect sense.

JDmills · #7 06-02-2009, 09:11 PM

Quote:

Originally Posted by Hatterasguy

I found a 3/8 rachet extension to work perfectly to release the tension. Take the nut off the bolt that holds the plastic thing, and stick the extenstion into the hole on top. Take the pressure off the bolt and push it back.

Once you do it once, it makes perfect sense.

I am feeling really stupid here.. have not even gotten to the point of pulling the old belt, due to not being confident about how to release the pressure..

Just as i am typing this, I had an flash of understanding.. that plastic thing that acts as a pivet, actually pivots around the little 10mm bolt on bottom, and the 13mm bolt that isin fact holding one end of the spring is the one that needs to be removed??? guess I am kinda leery of the spring tension here and not being real adventerous..

JDmills · #8 06-03-2009, 08:20 PM

Quote:

Originally Posted by Brian Carlton

If you are changing the belt, you must pay attention to the installation of the new belt around the tensioner. The end of the belt will not pass through the crankshaft and water pump pulleys. You must install the end over the tensioner pulley first and slide the belt in sideways between these two larger pulleys..........then work the ends around in a large circle.

The belt can be changed in 10 minutes........or it can take 10 hours.

Report back if you get "jammed up"............

success!!! well I have not had the car running, but putting the new belt on was not as difficult as getting the old one off. did not make in under 10 minutes, more like 30..

Now that have seen the light, NO i would not want to do it on the side of the road, but I admit that the system then designed is elegant.

Thanks to everyone for your help and support.

CSchmidt · #9 06-03-2009, 10:21 PM

"Other than your inspection shop, who said anything about removing the fan? "

The Mercedes 602/603 diesel engine manual. Their recommendations in section 13-342 says to take off the shroud and remove the fan. This may be more necessary in the 124 cars. All I was trying to suggest is that it is possible without removing the fan.

In my case, I'm sure this inspection station and the 25 year old inspector had never seen a 300SD (140) and went by some time/scale guide which included the fan removal and jacked up the cost.

CSchmidt · #10 06-02-2009, 10:10 PM

I have been able to change 2 belts on full sized cars ( an 87 and 93) without removing the fan. Just carefully route it between the fan and radiator.

The reason I say this is a local inspection station failed my 93 for "cracked accessory belt". It wasn't, they were just trolling for $. They wanted $175 for the new belt, most likely following a shop manual recommendation to remove the fan first. I discussed with the manager saying this was a 15 minute job and a $20 belt. He stood by his $175 estimate. I took the car home and changed it. Brought it back for re-inspection and said I was wrong, it was 20 minutes and a $25 belt. Last time I go there.

Make a diagram of the routing, or see if there is a diagram under the hood already. There are a lot of loops.

Bio300TDTdriver · #11 06-02-2009, 10:54 PM

Other than your inspection shop, who said anything about removing the fan?

Jeremy5848 · #12 06-03-2009, 12:38 AM

The handle of the factory lug wrench is a perfect took to hold against spring tension while you remove the bolt. BTW, in some engines there is something in the way of complete removal of the bolt (forget what) but you can pull it back far enough to clear.

ashedd · #13 06-03-2009, 01:01 AM

I am going to cut my fan shroud into a two piece on my 300D. I will tie it together with wire ties or something when it is installed. I am doing this because with my big hands I was skinning my knuckles on the radiator when trying to remove the fan with the shroud in place. I will admit I never tried to change the belt with the fan on.

Did you get the new belt on yet?

Abadjay · #14 06-03-2009, 02:10 AM

I have big hands as well. I took out the belt yesterday to change the old fan clutch to a new one designed for the OM606. I took off the belt without taking out the fan, but backwards was harder. I (and this is where I may be newb) found it easier to take out the fan and do the belt change. Having the belt on before the fan also helped me grip the water pump pulley to retorque the fan clutch.

Don't worry about it. I had a lot of doubts and I have to say after studying this:

R&R of Viscous Coupled Fan, Serpentine Belt Replacement W210 E300D

It was super easy! You can do it!

compu_85 · #15 06-03-2009, 09:32 AM

You don't need to remove the fan, just slip the belt between a couple blades and spin the fan to move the belt around.

-Jason