871 Ac belt tensioner removal

[DosGatos]

2011 prostar 871, small belt tensioner. Socket head cap screw is in tight. Thought I read somewhere on here about this being a problem due to bolting to aluminum structure.
Any suggestions before I have to heli-coil the thing?

[Waterloo]

If it is the little pulley/tensioner up top by the head and AC, you only need to remove the pulley. Gates makes a replacement for half the cost of Cummins, any good big truck parts store will carry it, FleetPride, NAPA, etc.

Use a good 6 point socket and gently work it back and forth, it should come loose. If it is that pulley I am thinking of, and not one of the lower big ones for the serpentine belt, the bearing in the pulley normally lasts a couple of years and then fails. Gates sells the entire pulley with the new bearing.

[DosGatos]

Bought the complete tensioner. Tried just using the wheel/bearing but new wheel doesn't mate to old tensioner.
Anyway, backed the bolt out about 4 turns before things went south and snapped off the bolt.
Helicoil it is.

[Waterloo]

Oh nuts.

[Moose]

(09-13-2019 )DosGatos Wrote:  Anyway, backed the bolt out about 4 turns before things went south and snapped off the bolt.

Ouch....

Rusty bolts are my kryptonite...

[Rawze]

(09-13-2019 )DosGatos Wrote:  Bought the complete tensioner. Tried just using the wheel/bearing but new wheel doesn't mate to old tensioner.
Anyway, backed the bolt out about 4 turns before things went south and snapped off the bolt.
Helicoil it is.

next time work it back and fourth a lot. let it cool a bit if it is getting real tight. Work it in and out many times and it will not break. It takes some experienced hands sometimes, or a bit of heat.

[DosGatos]

Did the back and forth. Threads were crumbling and making it worse as I went. No way to get a shot of pb blaster behind the assembly.

This is the only thing going for me now.

[Lonestar10]

to quote AVE tools dont break stuff the 200lb gorrila at the end of it does. lol

good luck sounds like no fun at all. had stripped one of the bolt holes in my intake that attach the EGR horn took 4 or 5 helicoils just to get that damn thing fixed not a fun time.

[DosGatos]

Well it's all back together. 1 hour job took 5. Mostly me walking between the truck and shop trying to remember which tool I was fetching. Two tensioners and an idler and they all got some never seize.