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Steady Eddie
03-13-2007, 03:19 AM
OK folks heres one for you.

2005 cargo 2500 Sprinter 188,000 miles.

While driving under 800 lb load I started hearing a low hum,after I had to down shift due to stupid drivers cutting me off right right before a red light. It would get louder as I increased my speed. After I unloaded and made it to a truck stop, I inspected under the hood and could see daylight through the drive belt. Was also able to put finger nail through the belt. It was splitting. I didn't think that was the cause of the noise I was hearing and after having the belt changed and the transmission serviced the hum was still there. At first it would come and go and seemed to be coming from the front right of the engine compartment. Runs fine no miss, shifts fine and runs great.

I inspected the air filter thinking it was restricting air flow causing the turbo to hum. Noise still there. While I was there I decided to go ahead and do my once every other month cleaning of the EGR Value. I dropped a tool that fell down into the fan well. As I was attempting to hand move the fan so I could retrieve the tool I notice the fan would not move. Should be a fan clutch on these Sprinters I thought. I finished my job on the EGR value and looked again at the fan. Looks like a fan clutch, if it was it was struck in the engaged mode. Come to think of it, my humming noise did sound almost like in the summertime fan noise trying to keep the engine cool. BTW no, it is not over heating.

Is there a way to free up a frozen fan clutch?
Would down shifting cause the fan clutch to freeze up?
Will it hurt to keep driving with a frozen fan clutch?

Thanks

talkinghorse43
03-13-2007, 04:11 PM
OK folks heres one for you.

Is there a way to free up a frozen fan clutch?
Would down shifting cause the fan clutch to freeze up?
Will it hurt to keep driving with a frozen fan clutch?

Thanks

Looks like from my '03 service manual the viscous clutch must be replaced.

Can't imagine there's anything you could do to make it freeze up, except store it in a horizontal position.

Shouldn't hurt anything, just burn more fuel. But, it should be a simple fix - just replace the viscous clutch.

chaozz
03-14-2007, 12:21 AM
once there stuck luck that you need to replace it.
it will take longer to heat up since fan is going full force
and i have seen them break so dont wait to long,
or you may end up buying a radiator