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la2baja
June 8th, 2005, 17:55
Hi guys. Back from the 500 and found a flaw in the pulley set up for the 351 ford motor (1995 f-150) that someone has surely changed already. In Rosarita beach I lost my belt as I was just getting off the highway. Pulled over and found that the tension/idler pulley had snapped the main bolt that mounts it to the bracket. The pulley was still held on by the spring but unable to create tension, or even keep the belt on it. The bracket is a big cast piece of junk that holds the alternator and is where the pulley bolt threads into it. We were 50 feet from a Napa auto parts (very lucky) so the quick fix was to get a shorter belt that was perfectly sized and skipped the pulley all together. It worked fine. My boy Steve had to run to NApa 3 different times to get an exact fit but what the hell we got home. Unless there is a better fix, I am going to drill out the cast steel that the pulley bolt snapped off in and replace the stock crap with a grade 8 bolt and an actual nut to insure that if it happens again I can replace it in the dirt without major issues. My question is..... Is there a better way? Has anyone redisigned this thing so the belt doesn't rely on such a flimsy little bolt? Can the motor/belt survive with an idler pulley that is not spring loaded and is manually adjusted? This is a chase truck, so it has to be dependable. I would love to just give it a shot and see if it works but can't afford to leave a race car stranded because I'm guessing at a fix.......
Oh, other options losing the whole serpentine belt for multiple belts to each system so if I lose one I can continue to run the altenator and power steering without a/c and uneeded stuff? Limp mode I guess.

Thanks for your input!

johnnyweb
June 8th, 2005, 18:29
i have a similar truck that is my prerunner, 94 f150 w/302 its the same system i have never had a problem with it. more then likely the bolt got loose and walked around till the bolt snapped off. or maybe the belt was stretched out and the pulley was maxed out and the belt blew off and got wedged in there and broke the pulley bolt. we run the same type belt system on our race truck with out ever having it fail on use. im sure you could fab up a tensioning system on your own but it probably would be easier to fix it and carry that spare smaller belt incase it happens again. then if it happens again fab up some thing custom. goodluck!!

la2baja
June 9th, 2005, 11:28
sounds good Johnny. If the belt and pulley lasts on a dedicated prerunner than I'll go with the original set up and keep the spare. My truck has light "prerunning" duties and the occasional emergency treks on the coarse to help our cars so I'll write it off as a fluke. We had back to back races for the last 2 weeks so my prep was not as thurough as I would have liked.
Thanks, I feel better already!

Ramsey_ElWardani
June 9th, 2005, 12:03
That same belt system is on the Stock Full F150 that we race in CODE Class 8. It has thousands of race miles on it since 1994 and no problems.