belt keeps flying off!!! help

[BIGSTAKN]

i have March pulleys and a smog delete. The belt length is 88.5, the tensioner is good. i have replace the tensioner pulley and idler pulley. The belt keeps runing off the ps pump pulley, and i cant get it to stop. With the belt off it seems there is a little in and out slap in the ps pumb pulley. Do anyone know what could be going on. thanks for the help. O and the engine has 94K if that helps at all.

 

[HISSIN50]

When you sight down the side of the motor, are all the pullies in alignment?

Good luck.

 

[CManT1914]

Sounds like it might be a hair too big. Mine kept getting thrown off the alternator pulley. I had u/d waterpump and crank pulleys, but the stock alternator pulley. The next size up was too large, so I put my u/d alternator pulley back on, and it took the slack up, and I haven't had a problem since.

 

[BIGSTAKN]

more info

the belt is wearing on the outside, the belt is the right size and reads right on the tensioner. like said the ps pump shaft has a little slap on it. The u/d pulleys that have been replaced are wp, alt, and crank.

 

[mootang]

check the alignment on the power steering pulley compared to the a/c and idler. you might need to press the pulley on further or pull it back.

or if there is excessive play you might need a new pump.

 

[RFMustangGT]

you said you replaced your idle pulley. did you get the right one. I know when I ordered my new one from advanced auto parts, the wrong one kept comming up in their computer. the one they would give me was too small and had no side ridgesto hold the belt. just a thought.

 

[BIGSTAKN]

thats it!!!

i did get the idler pulley was from advanced and your right it does not have the side flanges, do u have the part # for the correct idler pulley. Thanks a ton u all are a great help.

 

[Stanger007]

Something else to check...
When I installed my pullies (ASP) I put the crank pulley (I think it was this one) on backwards - the "front" and "back" were every so slightly different. Long story short is that it threw the belt when the revs when up.

 

[RFMustangGT]

i did get the idler pulley was from advanced and your right it does not have the side flanges, do u have the part # for the correct idler pulley. Thanks a ton u all are a great help.

I think I threw the box away but I have to go there tomorrow and they have it on my record. I'll have them pull it up.

 

[RFMustangGT]

also I bet the pulley is not smooth either but has grooves which hold they belt too. which is bad cause the smooth side of the belt runs on it.

 

[86bluecobra]

my march pulley have worn the side of the belt off (one rib wears off) turns out my ps pump pulley need to go be tweacked out a little. do likek hissin says and check to see if all pulleys are lined up.

 

[RFMustangGT]

PART NUMBER FOR ADVANCE IDLE PULLEY: 89001

ok, just called advance and they told me that teh part number was 89001. this pulley should be little bit wider, little bit bigger, smooth pulley surface, and has the sides on it. I've asked them why they have the wrong part in the computer but they do not have a reason. when I held my old one with teh one they got from the computer it was not even close. The person who helped me finally took me in the back and we just started going through boxes. I hope this helps you out.