How do I Release the Tension on the Serpentine Belt? - Diesel Forum

JimmyRice · 10-16-2009, 05:35 PM

I am in the process of replacing my Cam Position Sensor on my 04 F350. To get my big hands into the tight workspace, I had to remove the serpentine belt, lower radiator hose, and power steering pump. Actually it was pretty easy and the new sensor is in place. The whole thing took me less than 2 hours till I hit a snag with the serpentine belt. I muscled the belt off at the alternator but I cannot muscle it back on. I've tried a tool on the tension pully and cannot move it enough to give me slack. How in the world do I get the serpentine belt back on?

Texascadillac42 · 10-16-2009, 07:13 PM

There is a square 1/2" hole cut in the smooth pulley side of the tensioner that you can put a breaker bar in and relieve tension that way. You either need an unbelievably low profile breaker bar or do what I have done in the past.....

I am sure this is highly frowned upon.....

Take the 3 bolts out of the alternator, tip it forwards, slip the belt over the alt, making sure the belt is on all the pulleys, then push the alternator back down flat, and get the 3 bolts in. (I did this in a parking lot when the belt broke and I didnt have a lo-pro breaker bar with me.

JimmyRice · 10-17-2009, 01:44 PM

Well your advice was spot on. I had a tool I rented from the auto parts store but the angles were not correct so I had about 1/2 inch of throw after I got it connected. I ended up taking out the alternator bolts, tilting it forward to get the belt on, then bolting it back into place. There has got to be a better solution. Now I'm on a quest to find a Ford specialty tool for the job....or make one myself. The only reason I don't have a custom tool right now is because my oxygen tank was empty. I had the parts store's loaner in the vice with hammer in hand to customize it but no oxygen.

Anyway, the new cam position sensor is in. It was an relatively easy job till I tried to put the belt back on. Once I solve that problem, I think it's about an hour and a half to two hours to complete. And that included taking pictures and making a diary so I could post it here and help others. Truck starts but I don't know yet if I've fixed my idling and surging trouble. Time will tell.