LS1 Belt tensioner bad???

[my95z28]

They do wear out. Davids you could just push on the pulley and move it over far enough to get the belt on by hand, no wrench required.

[01badbird]

just looked at mine and in your 2nd pic your at the first "line"on tensioner and mine is between the other two.are you running undersize pulley (right belt) believe last numbers refer to length checking mine (running 25% underdrive)

[OIF1VET]

just looked at mine and in your 2nd pic your at the first "line"on tensioner and mine is between the other two.are you running undersize pulley (right belt) believe last numbers refer to length checking mine (running 25% underdrive)

I believe I am 25% under.. I bought the same belt that was on the car when the crank dampener broke.. What P/N do you have? Mine is: 6pk1930


How do u check the tensioner? I just looked at my pic and I see what you mean about the tensioner marks.. Mine looks very loose if yours is down by the 2nd mark...This belt has been on for over a year, so I don't think belt installation is the issue...

I have the ASP PN 948500 http://www.futralmotorsports.com/fms...asp?pf=1&pg=55
First pic, 4th part number..

[Formula Z]

larry you have the worst luck with stupid lil shit like this. get the katech

[1BADAIR]

put the belt on and post a pic of the marks on the tensioner

[OIF1VET]

put the belt on and post a pic of the marks on the tensioner

Will do..Pic posted in next post.. belt on..

[OIF1VET]

IMG_4344.JPG

[1BADAIR]

thats a replacement?
mine is in the same spot. not much tension.
the katech might help if the pulleys are inline.
vettes throw the belts too. the oneway bearing'd alternators help them

[OIF1VET]

thats a replacement?

replacement belt.. stock tensioner.. Will check dampener, but AC belt appears to be inline, so doubtful that's the cause..

Think a couple of these caused it to slip?

[01badbird]

small world running same one but with gatorbacks GTR-4060763 A/C is GTR-4040377 sorry not talking about your installation but short enough belt.heres picture of where my marks line up.I also use belt dressing couple times a year (makes it sticky).How is tension when you take rachet and take pressure off to change belt?maybe use torque wrench to see if enough tension?
engine closeup.jpg

[OIF1VET]

Hey Rick, yeah you're tensioner is much lower on the marks than mine.. So you're running the same dampener? I don't have a torque wrench, but with a 3/8th ratchet and socket I can easily move the tensioner to put on or remove the belt(don't get me wrong, there is tension, but seems to easy to me).. I did notice a small cut in my belt last night, going to order the belt you have and see how it goes.. Maybe my belt is a hair long, I bought it at autozone based on the belt I took off the car when I changed the dampener..

This your belt?
http://www.summitracing.com/parts/GTR-4040377/

[01badbird]

believe thats the AC this is the other http://www.summitracing.com/parts/GTR-4060763/ just looked at reciept.Maybe good idea to get new belt and see if marks change.if not has to be tensioner and doesn't hurt to carry spare belt so you don't have to chase down like someone else had mentioned they had to.have had good luck with the gatorbacks.If you get tensioner should have superman polish seen one and looks sharp!!also like I had mentioned last numbers are for length and on yours looked like i seen ---760 so slightly smaller so leaning towards tensioner.one time had to by-pass buddies power steering to get home and took string to get new length and had to be 6 rib and whatever the new length was for new belt (he kept driving it like that )

[OIF1VET]

believe thats the AC this is the other http://www.summitracing.com/parts/GTR-4060763/ just looked at reciept.Maybe good idea to get new belt and see if marks change.if not has to be tensioner and doesn't hurt to carry spare belt so you don't have to chase down like someone else had mentioned they had to.have had good luck with the gatorbacks.If you get tensioner should have superman polish seen one and looks sharp!!also like I had mentioned last numbers are for length and on yours looked like i seen ---760 so slightly smaller so leaning towards tensioner.one time had to by-pass buddies power steering to get home and took string to get new length and had to be 6 rib and whatever the new length was for new belt (he kept driving it like that )

Yea, I'll pick this up and see if the marks move... Thanks man..

[Lucky SOB]

Here's a picture of mine for reference

[Gaspo]

i had the same prolem as david. my belt fell off 3 or 4 times. the marks were still in the specifications range. i took off the belt, and turned the tensioner pulley. it made noise and didnt feel smooth. i went and bought a new one and havent had a problem. it didnt seem horrible but it was enough to cause the belt to jump and finally fall off. i just got a stock replacement from local parts store.