Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help




Go Back   PeachParts Mercedes ShopForum > Technical Information and Support > Diesel Discussion

Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 01-23-2013, 10:13 PM
Registered User
 
Join Date: Oct 2012
Posts: 28
UCA Seating Question

Hi All

I've been trying to diagnose a knock/croaking noise I get from the driver's side front wheel well when turning right and/or going over moderate sized bumps.

After inspecting I noticed that the driver's side UCA is seated in the spindle about 5-9 centimeters higher than the passenger side, I tried tightening with an extension which only served to strip the nut (which has now been replaced).

Nevertheless, could this cause a knock/croaking noise? The pics show the difference between sides (although they are not my images).
Attached Thumbnails
UCA Seating Question-uca_driverside_croak.jpg   UCA Seating Question-uca_passenger_nocroak.jpg  
Reply With Quote
  #2  
Old 01-24-2013, 11:10 AM
Registered User
 
Join Date: Oct 2012
Posts: 28
My apologies if I was not clear, the UCA is new, as soon as I put it on it began this noise. I did a lot of other suspension work too - lower ball joints, tie rods, brake pads, rotors, left guide rod mount, LCA bushing, shocks - and this is the only thing I can think of that doesn't look right. Also, these pics are not of my car, but illustrate the problem with the upper control arm not seating.
Reply With Quote
  #3  
Old 01-24-2013, 01:35 PM
whunter's Avatar
Moderator
 
Join Date: Dec 2003
Location: Metro Detroit, Michigan
Posts: 17,350
Hmm

Quote:
Originally Posted by dwylie34 View Post
My apologies if I was not clear, the UCA is new, as soon as I put it on it began this noise. I did a lot of other suspension work too - lower ball joints, tie rods, brake pads, rotors, left guide rod mount, LCA bushing, shocks - and this is the only thing I can think of that doesn't look right. Also, these pics are not of my car, but illustrate the problem with the upper control arm not seating.
Looks like a wrong part.
They should be exact mirror images, your pictures show variations.


.
__________________
ASE Master Mechanic
asemastermechanic@juno.com

Prototype R&D/testing:
Thermal & Aerodynamic System Engineering (TASE) Senior vehicle instrumentation technician.
Noise Vibration and Harshness (NVH).
Dynamometer.
Heat exchanger durability.
HV-A/C Climate Control.
Prototype Vehicle build.
Prototype Fleet Durability
Prototype vehicle instrumentation.
Technical Quality Auditor.
Automotive Technical Writer

1973 300D
1973 309D - stolen
1978 280SE
1980 240D
1983 300D
1984 190D
Reply With Quote
  #4  
Old 01-24-2013, 06:15 PM
Registered User
 
Join Date: Oct 2012
Posts: 28
whunter

I thought so too, "the part must be defective or wrong" so I returned it and got a new one. Same exact noise under the same exact situation, which would make me believe it is something else, but it appears to not be seating correctly which still baffles me.
Reply With Quote
  #5  
Old 01-25-2013, 12:55 AM
whunter's Avatar
Moderator
 
Join Date: Dec 2003
Location: Metro Detroit, Michigan
Posts: 17,350
Hmm

Is it possible a previous owner replaced one of the steering knuckles?
Call me Friday to discuss possible diagnosis/solutions.


.
__________________
ASE Master Mechanic
asemastermechanic@juno.com

Prototype R&D/testing:
Thermal & Aerodynamic System Engineering (TASE) Senior vehicle instrumentation technician.
Noise Vibration and Harshness (NVH).
Dynamometer.
Heat exchanger durability.
HV-A/C Climate Control.
Prototype Vehicle build.
Prototype Fleet Durability
Prototype vehicle instrumentation.
Technical Quality Auditor.
Automotive Technical Writer

1973 300D
1973 309D - stolen
1978 280SE
1980 240D
1983 300D
1984 190D
Reply With Quote
  #6  
Old 01-28-2013, 07:06 PM
Registered User
 
Join Date: Oct 2012
Posts: 28
perhaps...

whunter

Thanks for the input today on the phone, I am investigating the possibility that this older (1980) w123 had a newer (1981+) knuckle installed on it at some point.
Reply With Quote
  #7  
Old 01-29-2013, 12:42 AM
ROLLGUY's Avatar
ROLLGUY
 
Join Date: Oct 2007
Posts: 5,553
Having just done 2 front end rebuilds, are the knuckles different in 1980 and older form 1981 and newer? The reason I ask, is that I rebuilt a spare set of knuckles (new ball joints installed), and LCA's (new bushings installed) from a 1985, and installed them on a 1980. I then took the parts from the 1980, rebuilt them with new parts (BJ's & LCA bush'gs), and put them in my 1982 240D. I have the spares from the '82 that I will rebuild and use them in the next front end job. The '80 seemed to align just fine, and drives like a new car (suspension wise). I still have to get the '82 aligned after I replace the 2 tie rods tomorrow (after the parts arrive from Pelican Parts). Is there a problem with mixing up the parts like that? I assumed all the 123 chassis parts were the same......Rich
Reply With Quote
  #8  
Old 01-29-2013, 08:28 AM
Zacharias's Avatar
Not so amused
 
Join Date: Apr 2010
Location: West Quebec
Posts: 4,025
Quote:
Originally Posted by ROLLGUY View Post
Having just done 2 front end rebuilds, are the knuckles different in 1980 and older form 1981 and newer? .... Is there a problem with mixing up the parts like that? I assumed all the 123 chassis parts were the same......Rich
I had wondered about doing as well, swapping between my immobile '78 Coupe and my '85.
__________________


Mac
2002 e320 4matic estate│1985 300d│1980 300td
Previous: 1979 & 1982 & 1983 300sd │ 1982 240d

“Let's take a drive into the middle of nowhere with a packet of Marlboro lights and talk about our lives.” ― Joseph Heller, Catch-22
Reply With Quote
  #9  
Old 01-30-2013, 06:30 PM
Registered User
 
Join Date: Oct 2012
Posts: 28
yard investigation

Today I went to the local yard with one of the UCAs that I knew was not seating correctly on my wagon. I tested it on the following: 1978 116, 1985 123, 1979 123, and 1985 (?) 126.

The point of contact between the spindle and UCA ball joint ALL sat indentically (of course the lengths and exact configuration of the arm itself differed, but I wanted to see how that threaded section from the UCA sat when inserted in different spindles) the ball joint bolt has a tapered design at the top and can apparently be insterted approximately 5-10mm before directly contacting the actual ball of the ball joint - see the images above with the rubber bushing compressed between the two parts.

I'm baffled
Reply With Quote
  #10  
Old 02-01-2013, 01:08 AM
Registered User
 
Join Date: Oct 2012
Posts: 28
240d Spindle

So I looked at my neighbor's 240d today and it looks like the UCA sits a little bit higher than that of the 300d. Just a bit of qualitative assessment, but maybe about 1cm from being totally compressed against the rubber boot around the UCA ball joint.
Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT -4. The time now is 11:34 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2018, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2018 Pelican Parts LLC - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page