My alternator (Leece Neville) did the same thing while I was traveling in Northern BC. Belt also snapped.
From reading around on the internet, this scenario does not seem to be uncommon with Leece Neville alternators. Not sure if they make them cheaper for RV's or what.
I have a Cat C9.
In my case, there was enough room to thread the belt around the fan fins between the shroud to get it on the pullies. I am sure this is the case with yours as well. You are going to need two people to put the belts on, one putting the belt on the pullies reached underneath, and one putting the belt onto the pullies on top.
Removing and replacing the alternator will take some hand strength. On my alternator, there are four bolts holding it to the engine. Loosened the top two from inside the RV and the bottom two underneath it.
In my case, the alternator would not come down from underneath the RV because there was no room. Had to come out the top. This being the case, had to remove some Turbo and Exhaust lines that were preventing the alternator from coming out. This part took the longest as these turbo and exhaust hoses were really wedged on there.
I would recommend that you have someone else do this job, unless you lift weights on the side. Holding that alternator with your fingers trying to get it lined up, while using the other hand to jam the bolts in, all the while standing on your head is exhausting. This ain't no car alternator!
In my case, the ONLY belt supplier that makes a belt the perfect size with the perfect amount of grooves was Caterpillar itself. Others make some "close" or with less grooves, but I would rather go to the dentist than do this job again. Goes without saying that I ordered a spare belt to carry from now on!
