How to test suspension/steering (clunk/knock going over bumps)
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1983 E300D
How to test suspension/steering (clunk/knock going over bumps)
Hi guys need some of your help here to figure out where my mystery knocking sounds could be coming from.
The car is a United Kingdom spec 1983 E300D (none Turbo). There is a nocking/clunking sound whenever I brake or go over a pot whole in the road.
The Mercedes dealer and independent mechanics can only isolate the source of the sound to the front suspension but no further.
We are certain that it is not coming from the engine mounts, gearbox mounts, wheel bearings, springs, shocks or ant-roll bar. This just leaves the ball joints or other steering joints.
Here is the question is there any way to test the joints in the suspension and more specifically the bottom ball joints in isolation from the rest of the steering. Any DIY or videos you could put my way would be a huge help.
Thanks
James
The car is a United Kingdom spec 1983 E300D (none Turbo). There is a nocking/clunking sound whenever I brake or go over a pot whole in the road.
The Mercedes dealer and independent mechanics can only isolate the source of the sound to the front suspension but no further.
We are certain that it is not coming from the engine mounts, gearbox mounts, wheel bearings, springs, shocks or ant-roll bar. This just leaves the ball joints or other steering joints.
Here is the question is there any way to test the joints in the suspension and more specifically the bottom ball joints in isolation from the rest of the steering. Any DIY or videos you could put my way would be a huge help.
Thanks
James
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Answer
#1. Put a floor jack under the lower control arm, and lift the tire off the ground (1/2 inch clearance).
#2. Turn the wheel to give maximum clearance in the front.
#3. Use a pry bar between the lower control arm and knuckle.
#4. Bridge the gap with a finger while firmly trying to lift the knuckle with the pry bar.
#5. If you can feel motion across the gap, the joint is bad.
If this is a W123 chassis ?
I am confused by your model E300D (none Turbo) in 1983.
The E300 designation was first used in 1995.
I am forced to assume you have a 1983 300D.
There is a brake bracing kit in the lower control arm that can make noise.
MB# 1233301475
If the thumping is directly under the driver or passenger foot area, it is failed supporting joints.
MB# 1233301335
http://www.peachparts.com/Wikka/W123FrontSuspension
roy@pelicanparts.com
.
#2. Turn the wheel to give maximum clearance in the front.
#3. Use a pry bar between the lower control arm and knuckle.
#4. Bridge the gap with a finger while firmly trying to lift the knuckle with the pry bar.
#5. If you can feel motion across the gap, the joint is bad.
If this is a W123 chassis ?
I am confused by your model E300D (none Turbo) in 1983.
The E300 designation was first used in 1995.
I am forced to assume you have a 1983 300D.
There is a brake bracing kit in the lower control arm that can make noise.
MB# 1233301475
If the thumping is directly under the driver or passenger foot area, it is failed supporting joints.
MB# 1233301335
http://www.peachparts.com/Wikka/W123FrontSuspension
roy@pelicanparts.com
.
