Amazon: Knocking noise from rear of Amazon

[warninglight]

Hi all,

I'm hoping someone has had the same symptoms as I'm about to describe, and a fix...

I've just put my 1966 121 on the road, the first time it has seen the road in my ownership, and the first time in about 4 years.

When I'm driving along, when I accelerate, there's a 'clunk' from the back end, and when I lift off the accelerator, there's another 'clunk'

If I go on and off the throttle very gently, it doesn't do it, and the volume of the noise is directly related to how harshly I apply or take my foot off the accelerator.

It also makes a metallic knocking from the same area when going over rough road surfaces, but seems to not do this when accelerating.

Other than an oil change, the only thing I've done with the rear axle was to pop the drums off to check everything over.

Would love to hear suggestions from anyone who has had similar!

Stephen

[CLIVERALLY]

My P1800 did the same ..after doing alsorts and checking the trailing arm bushes it turned out to be a crap uj on the prop. Had them all changed and noise gone :-)

[tom the teapot]

Hi! Sounds like its the season for Amazon rear axle issues!

I also had a similar issue with my estate, I found on mine that on the stabiliser bar at the top of the axle the bolt hole for the bushes had worn slightly oval causing the axle to clonk as It either tilted forward or back. I found welding a beefy washer over the oval hole and tightening the bolt untill your face turns red helped!

The other clonk I found was the half shaft slightly moving in the drum, ie a worn out woodruff key, I cleaned up all the surfaces and re assembled doing the hub nut up tight.

I know the rear axle isnt the same but it may help.

Tom.

[Ron Kwas]

Stephen;

It sounds less like a drivetrain issue and more like a suspension issue to me because you noted that it "also makes a metallic knocking from the same area when going over rough road surfaces". I'd get the car on a lift and have a look at Trailing Arms, and particularly their bushings ... and maybe even firm tug by hand or lever with a big screwdriver or Tommy Bar (from the on-board Tool Kit)...it's unlikely that it's Panhard Rod, but it couldn't hurt to check its Bushings when you have the opportunity...also lift rubber trunk(boot)mat over Diff and check upper Damper mounts (not loose, and rod centered in hole through floor...loose hardware and Bushings which allows Rods to clunk against Body makes precisely the awful noises you describe!) ...I'd say something is either worn or loose or both...it's up to you to find it, but I wouldn't look inside Diff just yet...!

Good Hunting!

[Derek UK]

Some of these clunks can be hard to find. The MOT man might not have noticed that the tops of the shocks weren't being held snugly by the rubber mounts for example. He might just have been lazy and missed some obvious play. Check the rear U/J. You really need to get it back up on a lift if you can. Makes the checking so much easier.

[Need For Tweed]

I had a similar experience on mine a year or so ago. After a lot of head scratching it turned out to be loose wheel nuts on the offside rear! I regularly change the wheels on mine (I run a set of tarmac and a set of gravel tyres) and clearly became complacent. Tightened them up properly and the problem was solved. Hope it's something this simple for you!

[CLIVERALLY]

Speak as an MOT tester and in their defence they can only test what they can see and access without disassembly therefore if it were top shocker mounts loose unless they are visible from the underside and sway when grabbed then it would not raise concerns.