cummins 6b5.9 alternator failures
My 93 Winnie Vectra on a Spartan chassis with Cummins 5.9 is about to get its 3rd or 4th alternator in 70 kmiles. It had already failed when we bought the rig and the shop that replaced it had to cut...
Forum Discussion
DSDP Don wrote:
-Could someone have done a MacGyver fix years ago and changed out the tensioner or it's bracket with the wrong one?
-Could another tensioner bracket be used to move the tensioner out or the way?
-Could a longer belt be used to allow the alternator to rotate farther away and clear the tensioner?
That motor was used in a lot of applications and there could be dozens of tensioner/braket configurations.
Don
If there's something that wasn't per Cummins, I think it would have been Spartan. For awhile, I thought that maybe Spartan had moved the alternator to accommodate a narrow frame or other reason, but there is plenty of room there.
The tensioner pulley itself is the interference. It sits between the alternator and fan pulleys. Moving the tensioner pulley would change the belt tension. I don't see another location where the tensioner would fit.
The longer belt suggestion is a possibility. The alternator location is fixed by the brackets (3 mounting points --> not rotatable), but a longer belt will rotate the tensioner closer to the radiator fan pulley and further from the alternator. There is not much room towards the radiator fan pulley either, looks like less than 1 inch. But I've looked at the Gates belt chart, and the lengths near my 'original' are in about 1/2" steps, so I might be able to find one that places the tensioner in an OK spot. So far this has seemed like my best option, though I worry that if the belt stretches with age, does the tensioner pulley then contact the radiator fan pulley...
You are certainly right about the variety of applications. One nice feature to Cummins is that the ESN is supposed to determine the configuration. As near as I can tell, everything I can see looks like what Cummins shows for my ESN. Perhaps I could find another configuration that would allow an alternator fan, but rather than chasing down other brackets, I'd just put spacers under my present alternator brackets. This is probably the best way to go, so long as the bolts come out without breaking ...
thanks
Gary
