M117 4.5 Fan Clutch in a M116 3.5
 

Has anyone had any experience using a 4.5 fan clutch in a 3.5? Car is a W108. I hear it's possible but will just be louder than the 3.5 fan clutch? Will anything change aside from being louder and pushing more air? I'm having a hard time finding a good used Behr fan clutch for a 3.5 and I don't want to spend ~$1000 for a new one from the Classic Center.

Since the crankshaft-to-water pump distance is the same for M116 & M117 engines, the fan clutch from a M117 should fit the M116.
Noise is a function of the fan blade configuration, not a function of the clutch. If the fan blade(s) of the M116 will attach to the clutch of the M117, then there should be no change in noise, otherwise use the M117 clutch/fan blade package complete.

That makes sense. I didn't think of that.

Looks like I may just end up trying out a M117 Behr fan clutch and fan since it's much cheaper than the M116 fan clutch. Only place I can find a new Behr M116 fan clutch is the Classic Center and that's nearly $800 at my cost.:eek:

Link doesn't work.

Adsitco in Indiana is selling new fan clutches for $99



Tim Kraakevik
kraakevik@voyager.net
630 940-2420

I've been doing more research and the M117 fan clutch and fan blade will work on my M116.

I ended up ordering a new Behr M117 4.5 fan clutch today and will soon be getting a metal 4.5 fan blade to match.

Just be forewarned that a lot of parts warehouses store these units incorrectly . This causes the clutch to always run on even at highway speeds.

Rest assured, continued driving and cold/heat cycles will restore normal function so don't worry.

So the fan clutches have a "break in" period? I've read that they do and also that they don't.:confused:

The issue is not "break in", it is that if the clutch has been stored flat, i.e., at 90 deg. to the installed position, the oil will have migrated out of the operating chambers. If the clutch is stored on edge for a few days before operating, the oil will return to the proper location.

I see.

For now, I've found an 11 blade 4.5 fan and waiting to receive the new OEM Behr 4.5 fan clutch. Hopefully I get all this going in this weekend.

I have purchased a few fan clutches over the years. New ones for different cars. They are always packed in a box that will only allow them to be stored with them at an angle inside the box.

i had wondered in the past why they were not shipped flat. This would require less space to ship and to inventory.

Thanks for this little bit of knowledge. It will come in handy someday.

Quick update.

So the 4.5 fan blade I got was from a later model M117 (W116 chassis) which the fan clutch is recessed into the fan center causing the fan clutch to be pushed closer to the engine past the water pump and not allowing me to bolt it up.

Now I'm on the search for an M117 fan blade out of a W108/9 so the fan clutch sits flush with the face of the fan so I can mount the fan clutch to the water pump.

(Hope this all made sense)

Finally got around to installing the M117 4.5 fan blade and new Behr M117 4.5 fan clutch. Everything bolted right up to the M116 3.5.

This is a great conversion for anyone that doesn't want to risk using an aftermarket fan clutch or spend a fortune on a new Behr M116 3.5 fan clutch! :thumbsup: