Hey folks,
I have an awful noise that has been getting louder:

The video sort of shows the noise but in real life the noise has a bit more bass and is loud metal 'clacking' noise. It is quite noticeable from several meters away.
I thought it could have been the timing chain, but it is reasonably new, so is the water pump (and i took it off to check for play but seems fine) - so is this the type of noise a faulty oil pump makes?

Thanks!

 

I can't imagine an oil pump that still functions, making any noise.

Have you run it taking the drive belts off one by one??

 

Agree about pulling each belt one at a time and running it. If it still makes that noise with each belt off, pull the valve cover and check valve clearance with a feeler gauge (it's possible that a rocker adjuster nut broke loose and allowed the screw to back out). If that's good, check chain tension by pressing on both sides of the chain. Should be very little, if any give. Now check the chain guides by putting a little pressure on them with a long flathead screwdriver from the inside pressing outward. They shouldn't budge.

 

Yep! I had already removed all the belts one by one and the noise went away, even when i put all the belts back on. But as per usual, once i put a post on YotaTech, and try the same thing again, it was clear it was the air-con idler pulley, with way to much forward and back play - clacking and causing the rubber to squelch a bit too.
Thanks!

Anyway, i have another strange problem now - involving slamming the doors on the 4Runner and an erroneous relay, but i will do another post.

 

The a/c idler pulley has a staked bearing so the entire pulley has to be replaced. There are a few sources out there, 22reperformance.com is the one I used.

 

what unusual noise