gdgerland

Need to replace the idler pulley and belt tensioner on my E55. Looks like the cooling fan blade needs to come off to remove the shroud so I can have room to work. Anyone know what size hex bolts hold the fan to the fan clutch? Thanks.



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mufc

No need to remove the fan unless you really want to. If so, I think the easiest way is to remove the fan clutch from the water pump. You can rent the tool from Autozone for the fan clutch - 36mm I think for a ford clutch , these usually work if they have not been abused. You will need some way to hold the water pump pulley though, again there is a special tool for this also. Koch Tool has them. A strap wrench wrapped around the water pump pulley may also work
You can remove the bolt from the idler pulley with out removing the fan though but it is a tight squeeze for it to clear the fan blade. Just grind a small part of the fan blade with a dremmel,all that is needed is to remove about 2mm at the base of the fan blade and the bolt will come out. Tensioner can be replaced with out removing anything

gdgerland

Thanks for the quick reply mufc! I read about the Dremel trick, may have to try that. Saw a video on Youtube where the guy removed the three bolts from the fan blade, but he didn't know what size hex wrench to use (also said it was a PITA) The Autozone stores in my area don't have the fan clutch tools for rent, tried that.

Will I need to make additional notches with the Dremel to balance the blade? Not sure how sensitive it is to vibration.

Guess I will find out tonight. The idler pulley and tensioner appear to be original, can't believe they lasted 165,000 miles.

Thanks again for your help!

mufc

Balance really wont be an issue as the dremmel cut is so close to the fan hub and you only have to remove such a small amount of material. If I remember correctly, the fan blade pitch varies and there is one or two blades on the fan that will require less grinding so look out for this.
I would imagine the idler pulley in particular will be in much worse shape than you thought. The bearing will be loose and noisey but the worst thing is that the pulley itself will probably have huge cracks on the back of the pulley. I changed mine at about 100,000 and it was in bad shape. I am surprised it has lasted so long. Tensioner bearings will be shot also.

gdgerland

You are correct about the idler pulley. Bearing is very noisy, and when I removed the belt the plastic grooved portion of the pulley fell off in two pieces into my hand. I plan to replace the tensioner just because it is the original style and probably very worn. Otherwise, for 165k miles, the engine runs great. Hope to get another 165K miles out of it

Dave1965

You may want to just go ahead and buy a fan clutch removal kit off the internet. I got mine for around $40ish. I tried the rental tools at Autozone, Advance Auto, and O'Reilly's and none fit to my satisfaction.

Odds are that if you have the original fan clutch on your car, that it's "toast" anyway. Mine at 89,500 miles had the gooey/sticky/dust collection on the front along with no engagement at temperature that clued me in.

Replaced the old-style tensioner while I was in there and it was SOOOOOO easy with the fan clutch removed.

Some advice: As you are facing the car with the Driver's side on your right, you'll want to turn the 36mm nut on the fan clutch TO THE LEFT (counterclockwise) to loosen!

Nocturnal-G

No need to remove the fan clutch.

If you have a hex key set, I can't recall the size... but it should be around 5mm.

Remove all but the last... on the last one, loosen it only a bit... but do not remove it. Move the fan, pull the bolt, put the hex fasteners back in. DONE.

TIP: Remove the fan shroud for access... remove clips, pull straight up.

gdgerland

Dave1965 and Nocturnal-G, thanks for the responses guys! I managed to get the job done using the Dremel to notch the fan blade. However, I did notice some slight play in the water pump pulley before I re-installed the belt. Guess a new water pump will be needed soon. Dave1965, I did order the Kommen fan clutch tools on ebay, thanks for the recommendation. Read in another post that some of the 36mm fan clutch nuts are reverse thread, some are not. Anyway to tell which visually?
Nocturnal-G, loosening the shroud helped a lot, gave a little more room to access the bottom bolt on the tensioner. Trying to access the hex bolts on the blade was tricky.
Thanks again for all the help guys. Between repairs on the E55 and the E320, this forum has saved me about $3000. As I get more experience with these machines, I hope I can contribute too.

Dave1965

I haven't heard that?

You'd have to have 2 other part numbers...one for the "other version" fan clutch and one for the "other version" waterpump.

My M3 loosens the opposite direction of the E55 but its engine rotates the opposite way as well. And of course, as a M3, the fan clutch removal tools were TOTALLY incompatible with the E55's.

Nocturnal-G

The whole point of loosening the fan was to pull the idler pulley bolt... I suggest you order a new fan when replacing your water pump.