84 500SEL... bad steering knuckle and brake caliper.. help - PeachParts Mercedes-Benz Forum

shawnh · #1 10-02-2010, 06:41 PM

I just discovered that the steering knuckle is cracked where the ball joint is... this explains the clunking I have heard. I was changing the front break pads, only to find the calipers are leaking on the left side... soaked with break fluid. After this I did more inspection and found the fracture in the steering knuckle.

My questions are:

1. Are parts from other 126 cars compatible with the 500SEL, if so which cars/parts etc... ???

2. Would it make sense to rebuild the caliper seals???

3. I also need an axle assembly... should I just throw the car away???

thanks

John1 · #2 10-02-2010, 06:45 PM

How many miles on it. Yep, W126 front ends are interchangeable .

Mine also is a 84 500 sel.
Rebuilt whole front end and brakes now the trans. It is a great car

God Bless
John

shawnh · #3 10-02-2010, 06:54 PM

Quote:

Originally Posted by John1

How many miles on it. Yep, W126 front ends are interchangeable .

Mine also is a 84 500 sel.
Rebuilt whole front end and brakes now the trans. It is a great car

God Bless
John

Thank you so much John. I just found a steering knuckle on ebay with ball joint installed, looks pretty good. 59.00.

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=150300774740&viewitem=&_trkparms=algo%3DLVI%26its%3DI%26otn%3D2&category=42609

The car has somewhere over 235,000 miles on it. odometer not working. Service records of first 160,000 miles looks great. Runs good, does not use oil... It has been basically parked for a few years before I got it. I am going to order an axle assembly on monday... a little grease through the cracked boot has quitened it down. Now I need the steering knuckle and break caliper. Do you think I should rebuild the seals in the caliper?????
The bushings under the front end look amazingly well for a car of this age.

I can't believe I had this car over a hundred mph with all these problems... when i was testing it out!!!!!!!

Thanks again,

Shawn

John1 · #4 10-02-2010, 10:29 PM

Quote:

Originally Posted by shawnh

Thank you so much John. I just found a steering knuckle on ebay with ball joint installed, looks pretty good. 59.00.

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=150300774740&viewitem=&_trkparms=algo%3DLVI%26its%3DI%26otn%3D2&category=42609

The car has somewhere over 235,000 miles on it. odometer not working. Service records of first 160,000 miles looks great. Runs good, does not use oil... It has been basically parked for a few years before I got it. I am going to order an axle assembly on monday... a little grease through the cracked boot has quitened it down. Now I need the steering knuckle and break caliper. Do you think I should rebuild the seals in the caliper?????
The bushings under the front end look amazingly well for a car of this age.

I can't believe I had this car over a hundred mph with all these problems... when i was testing it out!!!!!!!

Thanks again,

Shawn

Nope, I would just replace the caliper!

John

Hit Man X · #5 10-02-2010, 11:52 PM

Throw the car away?

Just put a few dollars into it and keep driving it. Any used car will pretty much need the same stuff. If you have no records of the timing chain guide rails being replaced, make that a top priority!

Do you have access to a junkyard? That price seems mighty high for a knuckle with a bad ball joint on feebay. At the very least replace the upper control arm and the ball joint on that side you are operating on then inspect the other side. Inspect closely the strut/guide rod as they are usually bad on these cars making the front end 'clunk'... install on them is very simple. You just need a good alignment afterward.

Ask in the parts section here, maybe someone will give you a better deal on the knuckle.

Inspect both rear axles close, if one has failed the other is going to also unless the PO replaced one instead of the other. Since you have to pop the cover to R&R the one... you may want to consider doing both while in there. I would also do the diff mount as they are a breeze to install and pretty inexpensive. Probably the rear sway bar links due to low cost and easy access.

I agree with John1, just replace the caliper if in doubt. Same with all four rubber brake hoses and a good flush with DOT4 if the car has been sitting. I typically do brake work on a 'per axle' basis... meaning I replace items in pairs such as calipers in pairs, rotors in pairs, etc.

shawnh · #6 10-03-2010, 01:03 AM

Quote:

Originally Posted by Hit Man X

Throw the car away?

Just put a few dollars into it and keep driving it. Any used car will pretty much need the same stuff. If you have no records of the timing chain guide rails being replaced, make that a top priority!

Do you have access to a junkyard? That price seems mighty high for a knuckle with a bad ball joint on feebay. At the very least replace the upper control arm and the ball joint on that side you are operating on then inspect the other side. Inspect closely the strut/guide rod as they are usually bad on these cars making the front end 'clunk'... install on them is very simple. You just need a good alignment afterward.

Ask in the parts section here, maybe someone will give you a better deal on the knuckle.

Inspect both rear axles close, if one has failed the other is going to also unless the PO replaced one instead of the other. Since you have to pop the cover to R&R the one... you may want to consider doing both while in there. I would also do the diff mount as they are a breeze to install and pretty inexpensive. Probably the rear sway bar links due to low cost and easy access.

I agree with John1, just replace the caliper if in doubt. Same with all four rubber brake hoses and a good flush with DOT4 if the car has been sitting. I typically do brake work on a 'per axle' basis... meaning I replace items in pairs such as calipers in pairs, rotors in pairs, etc.

Very good info here. Thanks.

I am going to a junkyard tomorrow... about 70 miles to the closest one. They have 2 126 cars on the lot. Will try to find as many good parts as parts as possible while there.

Neither axle has been replaced, ever, from the looks of things. It appears as though the right axle can was damaged by road debris at some time, and there is a very nice cut in the cv boot that was hard to find. The rubber is really not dry and brittle. It looks like a knife cut. I will hopefully find 2 good axles at the junkyard, since mine are the homokinetic type and I am really not into paying the dealership almost 300.00 a piece for the differential flanges.

thanks again for all the advice.

david s poole · #7 10-03-2010, 11:07 AM

info that might be useful:sometimes a caliper will leak when brakes are worn out and piston extended.by fitting new pads and pushing piston back in i have found that leaking will stop and at least buy some time.

shawnh · #8 10-04-2010, 01:18 AM

Quote:

Originally Posted by david s poole

info that might be useful:sometimes a caliper will leak when brakes are worn out and piston extended.by fitting new pads and pushing piston back in i have found that leaking will stop and at least buy some time.

the pads looked brandspankin' new. obviously the installer damaged the caliper the last time the pads were changed.

I went and pulled a steering knuckle today, with a good caliper. It has rim stuck on it, and i am going to try to get it cut off with a cutting torch tomorrow. I spent hours today trying to get that broken lug bolt out... finally gave up. I started pulling axles, but the yard was closing, so i had to quit until tomorrow. I found annular axles and did not realize i had to separate them at the flange to remove them. The donor car is a 1990... 126 body... don't remember the class. will these axles fit my car????

I forgot my toolbox and sunglasses at the wrecking yard... I hope they will still be there tomorrow... 160 mile round trip to yard... fun times.