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Been experimenting with pulleys and noticed sloppy idler every time it's been apart. 1st time thought I just forgot to tighten the bolt, 2nd time thought it wasn't tight enough, but it still loosens up after running.
The bolt is always tight, just that the threads of the 3/8 bolt have a lot of clearance and a loose fit inside the pulley adapter so as the bolt stretches, it doesn't hold the idler by the face and then rocks between the bolt and adapter. I also had to shim the idler with a spacer so it doesn't rub on the bracket which seems a little odd.
Thinking about using a threaded rod rather than a bolt so I can just tighten the nut on the end every once in a while but there has to be hundreds of setups running these things so I've got to be doing something wrong.
2020 Corvette of the Year Finalist (performance mods)
C5 of Year Winner (performance mods) 2019
maybe try a little bit of blue loctite to keep it from backing out... it would probably benefit from a properly machined shouldered collar to support the idler bearings and bolt ...
Phil, Do you have a lock nut on there, or a lock washer and standard nut?
Secondly we do not put a washer under the "properly machined idler adapter". That might cause an issue.
A while back we noticed that the lock nut would back the bolt out while adjusting, causing the bolt to snap once it was loose. The fix was to lock tight the bolt into the bracket and replace the lock nut with a std nut and lock washer. I am not aware of any failures to date since that correction.
I applied some Hi-Strength LockTite on the threads and tightened the crap out of it. Have a hunch Doug is right about the bolt backing out when tightening the nut on the adjustment, and yes I'm using a stainless 3/8 nut, lock and flat washer to lock the adjuster down.
As for the washer...I have to use it or the side of the pulley rubs on the bracket..not much, maybe a few thousands or so, but it does rub without the spacer.
It's all back together and I'll keep an eye on it... Thanks
I applied some Hi-Strength LockTite on the threads and tightened the crap out of it. Have a hunch Doug is right about the bolt backing out when tightening the nut on the adjustment, and yes I'm using a stainless 3/8 nut, lock and flat washer to lock the adjuster down.
As for the washer...I have to use it or the side of the pulley rubs on the bracket..not much, maybe a few thousands or so, but it does rub without the spacer.
It's all back together and I'll keep an eye on it... Thanks
PM me and I'll send you a new one so you do not need the washer, or try and just flip the idler over. They are spaced differently front to back.
Last edited by DOUG @ ECS; 10-12-2017 at 09:30 AM.
10-11-2017, 10:21 AM
1500SL Adjustable Idler Pulley loosening
