Idler tension arm jumping up and down causing rattle

[aussieghostrider]

AS the title says the arm starts jumping up and down when engines warm and when engines off I can push down on the pulley and the arm creeks and moves a notch or two, the pulley is fine and making no noise as was replaced couple years ago.

It only does it now and then and only does it when in traffic with brake applied and in gear but occasionly does it when in park...

The car used to have a miss but has gone since fitting a new vp coil pack and dfi so it cant be that.

I want to know how much is a fair price for the average mechanic to get done as I plan on calling around to see whats the best price ..

I live in Sutherland shire in sydney if theres any mechanics out there who want some work from a fellow JC brother....

[Snap-on]

I had exactly the same problem in my VT. What happened with me is that the air con compressor pulley was not spinning, which created the tensioner to chuck a skits like yours does. Turned out I put too much lube on the belt, which meant it couldnt grip on the ac pulley properly so the tensioner was jumping back and forth with the differing belt tensions. Try drying off the belt of all grease etc and give it a go. If not, rip a mate in and have a look yourself when it starts to happen - could be the same thing.

[Sharpie]

i had the same issue last week. New belt fitted and idler pulley but still that annoying rattle/knock. The fix... The arm is spring loaded and what that knock is the arm moving forwards and backwards slightly. Grab a srewdriver "a massive flat head" and "tap/knock in" and front black retaining bracket 1 mm to make the arm have more resistance, less end float. Knock gone.

Cheers Steve Subaru Sti Melb.