Alternator & A/C Pulley Not Lining Up After Replacing Brushes

[wolfe10]

4 hours ago, garyreed said:

Does the waterpump belt look ok and the pulley aligned? Is it a v-belt or serpentine? The crank pulley should be both the main belt and the water pump, so in theory if the water pump belt should be tracking off also.

Gary

Yes on the Caterpillar 3126, the water pump is on a separate V belt (crank, idler, water pump).

[Losciuto]

Gary,

The system has two separate belts, V belt on water pump and then micro V serpentine belt for ALT and A/C.

The engine only has 40K miles on it, the original belt was replaced before the RV was put into long term storage a couple years ago.  The second belt only has about 10 hours from running the engine while in storage.  I can see the grooves are a little wider than the new belt I just bought and put on but the belt looks good.  I replaced it because I could not really find the true issue and felt it was worth a shot to replace it.

I have checked all the pulleys for play and not found any. I checked the crank pulley as best I can and found no play in it.

[garyreed]

Did the second belt ride up on the A/C also or just the last belt? How about the first belt and what was the reason for changing the brushes? There is nothing you have done so far that would change the alignment of the belt with the exception of the tensioner and you have had it off and on and swapped enough times you would have caught it if it was not mounted properly

As far as the width of grooves on the #2belt it makes me think that it may have been slipping probably on the crank pulley and has worn down the ribs. If there is rubber in the groove of those pulleys, It might cause the belt to jump and may force it of a pulley but it usually happens when the motor is running. Does the A/C compressor engage when the ignition key is on? If it does, will it still spin freely, maybe not freely but still turn smoothly?

Sorry for all of the questions and not to many productive answers You will get it I promise.

Gary

[Losciuto]

I don't believe the brush issue and belt issue are connected.  The spring failed on the brush and it didn't make a connection. I am going to try to get the grooves cleaned on the crank pulley.   I need to investigate the AC closer.  I have been watching it from the back as that's were the belt is coming off.

[garyreed]

I think you are right, after all that thing went 40000 without much problem. It is just finding out which issue is fouling up the works.

Gary

[manholt]

One picture of the whole system...not one segment at a time as earlier posted...would be a tremendous help!

[Losciuto]

Gentlemen, At lot of testing and measurements has finally paid off.  It appears that the alternator was not sliding on the bushing properly.  The alternator was angling slightly causing the belt to be pulled off the ac pulley. The fix was to put a washer on the bolt which caused the bushing to tighten up to the alternator. I also had to use a crowbar under the alternator to take the angle out of the pulled on the alternator.  I have run it for 45 minutes on three seperate days without any issue.  Hopefully, this solution holds.

Thank you to everyone who helped, it gave me some good ideas to trouble shoot to solve the issue.

[rsbilledwards]

Thank you for giving the solution as it brings this thread to a nice conclusion. I only now discovered it having been on the road. I could have shortened it a bit as I had the same issue on my Safari Zanzibar some years back. Makes you smile when "you" find the solution. Good Job!

[wildebill308]

Great! glad you got it sorted out.

Bill