Tighten Alternator Belt

[AllDunn]

Hi, I have a squeak in the front end of my 02 1150RT that sounds like a loose alternator belt. Do I need any special equipment to tighten the belt and can I get at it from the front of the bike by taking off the housing plate - or do I need to take off all the tupperware? I looked at it last night and it seems straight forward. I looked up the parts on fiche but I do not see a mechanical tensioner. Has anyone ever had to do this before?

[RFW]

Hi, I have a squeak in the front end of my 02 1150RT that sounds like a loose alternator belt. Do I need any special equipment to tighten the belt and can I get at it from the front of the bike by taking off the housing plate - or do I need to take off all the tupperware? I looked at it last night and it seems straight forward. I looked up the parts on fiche but I do not see a mechanical tensioner. Has anyone ever had to do this before?

 

Pull the cover off and have a look. Ought to be obvious once the cover is off.

 

Bob.

[AllDunn]

Thanks Bob, I'm wondering if I need to get a device that will tighten the belt or is there a bolt or something that will do the work for me?

[lazywizard]

Make sure you take off the alternator cover which is fitted on top of the front engine cover. 4 hex drive screws. Then inspect the belt, feel it for stiffness or broken ribs or tears. Get a sense for the tension. Replacing it is simple. Loosen the alternator, witness the location of the tensioner accessed from the rear with a hex drive, left side of the bike. Replace the belt. I did not have the correct extension to use the tensioner so I levered the alternator up with a large screw driver and tightened it down. 30 min cover to cover.

[Rob L]

There is a whole procedure which must be followed using a special BMW tool...........or you can loosen the bolts and pry under the alternator until you can just turn the belt 90° at it's midpoint. This is the way I tighten it and it seems to work after 30k miles without retightening

[Gail]

You can adjust the tension from the front of the engine without a special tool. The tensioner is an allen head bolt that was designed to be used from the back side of the belt housing. The problem is that it is almost impossible to do without removing the fuel tank.

 

From the front of the engine, remove the locknut on the tensioner and replace it with two nuts threaded onto the bolt and jamed together. You can apply the specific torque of 8Nm to the jammed nuts. It is very easy to do. Here's a pic. that might help.

 

Gail

[AllDunn]

To all,

thanks the information is great and I will tackle the job myself this weekend. Because the bike only has 18K on it I'm going to try tightening it first, otherwise after my courage is built up I'll replace it!! Gail, your picture is excellent.....

[Ken H.]

The tensioner is an allen head bolt that was designed to be used from the back side of the belt housing. The problem is that it is almost impossible to do without removing the fuel tank.

Actually, presuming you are talking about the BMW tensioner tool, not true.

 

The tool replaces the retaining nut on the FRONT of the bell housing during tensioning. You replace the nut with the tool, set a specific torque value with the tool, hold it, tighten the other two alternator retaining nuts, then remove the tool and re-install the original nut.

 

That being said, it's true, you don't have to have the tool. The old 90 degree twist rule seems to work fine.

[TonyS]

A "knuckle" adapter for a ratchet let me easily access the adjuster on the back of the alternator. The gas tank is not in the way at all. I set the torque wrench for 8nm and turned the adjuster COUNTERCLOCKWISE to correctly set the tension. This was followed by the 90 degree bend of the belt check. The hardest part was figuring out to turn the adjuster the opposite was I had expected.

[Clive Liddell]

No one has mentioned the R and R of the cover which requires removal of one fairing and shark fin holder. I cut my RT cover across allowing easy removal of each piece for inspection etc.