Broken belt tensioner

hello every one out there … heres a problem a 2004 ford focus v tec…keeps destroying belt tensioners seriously breaks them in half ect everything else checks ok.alt/comp / idler/wp spin free w/no noise…makes noise with ac on shop said it was comp…1000. later still destroys tensioner.any ideas thanks

Did you recently change the belt? If everything is in alignment then the tensioner should not be affected. Double check the part# on the belt. One that’s too short will play havoc on the tensioner.

When the tensioner and belt are new, does the belt run smoothly or is the tensioner hopping up and down?

When the A/C is on it jumps eraticaly. Everything seems to be in line. This is the 3rd pully and 4th belt to break in 6 months.

The 2nd belt was replaced with the incorrect size at a local shop. I have replaced 2 more of the correct size. Now that belt is shredded along with a 3rd tensioner pully destroyed. Previously the compressor had been replaced as well.