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Alternator belt replacement 2004 1150RT

Beemahdad

86 K75 vin 0114638
I noticed my alternator belt starting to squeal a few weeks ago and had plans to replace this weekend. After watching a few videos and armed with my Clymers, I got as far as far as loosening the 3 and 9 o'clock nut and bolt to the belt adjusters but am having difficulty with the 12 o'clock nut. Do I loosen it by counter clockwise or clockwise? I rounded off the nut unintentionally and am now afraid to do further damage because it's a tough location to access and socket or wrench for that matter.

Any clear advice you can share. Please include the direction I should turn... Like the normal counter clockwise or clockwise for the 12 o'clock adjustment nut?

Thank you
 
The nut/bolt at the 12 o’clock position unscrews in the conventional direction.

A couple questions come to mind: are you sure it’s the belt? Do you have the tools and know the procedure for re-tensioning the belt? My 2004 RT had a post start squeal that I though was the belt but turned out to be poor lubrication of the starter drive.
 
The nut/bolt at the 12 o’clock position unscrews in the conventional direction.

A couple questions come to mind: are you sure it’s the belt? Do you have the tools and know the procedure for re-tensioning the belt? My 2004 RT had a post start squeal that I though was the belt but turned out to be poor lubrication of the starter drive.

Hi. Thanks for the quick reply. It's definitely the belt. It's old and cracked. I bought it at 92k miles and it's now riding with 127k miles. I can't even see the writing.
 
If you are not close to a dealer, the belt that is a good substitute is a Dayco 5040240, available from auto parts dealers. The units I bought were made in Canada.
 
Looking at the nut from the front, counterclockwise.
Thank you Paul
If you are not close to a dealer, the belt that is a good substitute is a Dayco 5040240, available from auto parts dealers. The units I bought were made in Canada.

Thank you. I have a replacement but understand there are 2 sizes depending on your year? Without the writing on the old belt the replacement looks smaller. I got the Continental
 
Thank you Paul


Thank you. I have a replacement but understand there are 2 sizes depending on your year? Without the writing on the old belt the replacement looks smaller. I got the Continental

If you got the smaller one then I believe that’s the correct one for the 1150. The slightly longer one is for the 1100 (except R1100S). I know because I just bought one for my 1100.

Denny
 
Looking at a parts diagram (Bike Bandit) your 12 o'clock mount is the same as my 97 RT: a long 13mm-headed bolt, a threaded spacer shaped like a flat-sided igloo, a shim that is basically a flat washer, the hole at 12 o'clock through the alternator support cover, then the shouldered nut you are having trouble with. Removing the front spring strut/shock should give you better access to the nut, and turning the bolt at 12 o'clock may help loosen the nut. Both of these would mean removing the gas tank for access though.
Or it may be a matter of just getting a good 6-point socket on the nut to break it loose. Hope you have some luck.
 
4 months later

Finally got the belt replaced after a prolonged period watching the front end taken apart with the old cracked belt shouting at me to replace her. I eventually took the front strut off and got a 13mm socket onto the stubborn nut and BAM it loosened and the cracked belt came off. I discovered that the cheap combination wrench I purchased was slightly larger than 13mm so that's why it wasn't grabbing and gave me the impression I was rounding the head. I also was surprised that my fear of the possibility of more troubles removing and replacing the strut was unfounded. I thought it was under compression and there would be difficulty during the reinstall.

The next problem I encountered was that the new Conti belt was undersized and i scrambled to find a car parts place that was open on the long weekend that had a belt that would fit. Success and I found an AC Delco alternative that I installed and am happy to report the ride is back on the road.

Thank you for everyone who commented.

Happy riding and stay safe!
 
Success and I found an AC Delco alternative that I installed and am happy to report the ride is back on the road.

Thank you for everyone who commented.

Happy riding and stay safe!

Glad you're up and running again.

There are many folks in your local club who would have been happy to assist you.
 
I discovered that the cheap combination wrench I purchased was slightly larger than 13mm so that's why it wasn't grabbing and gave me the impression I was rounding the head.

Experience has taught me that there are few things more expensive than cheap tools.:banghead
 
New Belt "tight"

Hijacking this thread a bit. I also have a 2004 1150RT and am replacing the alternator belt. The one I took off was a BMW part and probably is original (36K miles).. is a 841 belt and I bought the same belt from Beemer Boneyard, when I loosened up the alternator the old belt while not "following" off came off without too much difficulty. The new belt is a struggle, I will have to leverage it on while turning the motor over... Is this "normal" for this bike?

Thanks
Royce
 
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