Enlighten me on alignments for my W123... - PeachParts Mercedes-Benz Forum

dieseldan44 · #1 08-31-2009, 04:32 PM

Folks,

I just replaced my entire front end on my '85 300D. Before I replaced anything, the car pulled a little bit right.

Had the car aligned today at a reputable European auto shop. The adjustments I tried to estimate counting threads were way, way out before I took it to the shop. The shop did the alignment and the car now pulls to the right *exactly*, and I mean exactly like before.

I took the car back and the shop manager, who was very knowledgeable with W123's, mentioned that it could be an overtightened or undertightened wheel bearing, or something else outside of the alignment.

Thoughts on what to check??

dd

PS

Here's what I replaced (all Febi/Bilstein or OE):

- front tires with new Michelins
- UCA's, LCA's, all bushings
- guide rod mounts, front and rear
- track rod, tie rods, steering shock
- rebuilt idler arm bushing
- new shocks (Bilstein comforts)

tangofox007 · #2 08-31-2009, 04:54 PM

Pulling can be entirely a tire/wheel issue. Swap the front tires and take a drive.

okyoureabeast · #3 08-31-2009, 04:56 PM

How much pull is there to the right? My mechanic informed me that a little bit of pull to the right is normal since the design of the power steering had it on the right side of the vehicle.

tangofox007 · #4 08-31-2009, 04:59 PM

Quote:

Originally Posted by okyoureabeast

My mechanic informed me that a little bit of pull to the right is normal since the design of the power steering had it on the right side of the vehicle.

Find a different mechanic!!! That one is dyslexic and confused.

Scott98 · #5 08-31-2009, 06:43 PM

Quote:

Originally Posted by okyoureabeast

My mechanic informed me that a little bit of pull to the right is normal since the design of the power steering had it on the right side of the vehicle.

WTF???????

Junkman · #6 08-31-2009, 06:55 PM

Post what specs the alignment was set to. I haven't had to align the SD but different camber (cross camber) can cause a pull as can toe. (Google for alignment theory.) These cars are a dream to drive when set up correctly. Meaning that road crown wouldn't have so much effect that you would constantly notice it. Start with the simple stuff ie tire radial pull but you need to know the specs. I once drove treads off a set of tires (40,000 tedious miles) because I was young & didn't know how to make the shop stand behind the new tires I'd bought. FWIW, Firestone offers a lifetime alignment for approx $140. Their techs can be idiots but at least you have repeated access to the machine until they get it right. Your current shop hasnt fixed it so multiple cheap alignments may be the ticket.

okyoureabeast · #7 08-31-2009, 09:29 PM

Quote:

Originally Posted by Scott98

WTF???????

I most likely misinterpreted him and forgot nearly everything he said :-P

Then again I'm always on the hunt for new indys!

tobybul · #8 08-31-2009, 10:10 PM

alignment on the w123 does not require a european auto shop nor an mb dealer. A shop with a computerized laser unit will be able to align the car.

I happen to bring all my cars to our Ford dealer who has a dedicated alignment guy and uses a laser unit. I always watch him do it and appears to be easy to do. Generally, its just been adjusting the tie rods. Plus, the video interface looks pretty cool.

rrgrassi · #9 08-31-2009, 05:24 PM

Sometimes the car can pull due to the crowning of the road. How does it do on a totally flat road?

Skippy · #10 08-31-2009, 06:11 PM

Check bearing play using a dial indicator. If that comes up correct, then look for a dragging caliper.

Diesel911 · #11 08-31-2009, 08:09 PM

Quote:

Originally Posted by Skippy

Check bearing play using a dial indicator. If that comes up correct, then look for a dragging caliper.

The above is the best advice.

Make sure your Tires are inflated properly.

Did they give you a cpoy of the Alinement spec that they set it at?

dieseldan44 · #12 08-31-2009, 09:27 PM

Thank you for the replies.

The pull has happened over two sets of Michelins - I had the new Michelins for 50 miles before I redid the front end and the pull was there.

On the highway today I noticed one stretch on flat ground that the car was pulling the other direction - but 95% of the time it pulls right. Maybe I do indeed have a wheel bearing loose or something.

I just re-did the front brakes with new ATE calipers, so I know I dont have a caliper dragging.

I dont have a printout. Maybe Ill go back and ask them for it...but...I am not suspecting the alignment itself since it is now right back the way it was before - with an entirely new front end.

Tomorrow I'll:
- check tire pressure
- check runout on front bearings
- ? anything else I can check ?

dd

kingdoc1 · #13 08-31-2009, 08:06 PM

I would definitely suspect the tires first, usually that is the problem.

Sometimes the mechs doing the alignment don't understand that the right caster needs to be set slightly higher than the left to compensate for road crown, maybe they are just looking at the colored numbers on the screen and don't really understand what they are adjusting. Ask for a printout and post here so we can look at it.

#14 09-01-2009, 08:02 AM

It's almost a certainty that this is a tire issue.

dieseldan44 · #15 09-01-2009, 08:24 AM

tobyul - Ive sort of gone with the whole notion that a euro shop needs to do the alignment since ive seen it here over and over. So aligning these cars doesn't require ant fairy dust? Id be happy to learn thats not true, because my usual sans-euro fairy dust indy is about half the cost.

Quote:

Originally Posted by LarryBible

It's almost a certainty that this is a tire issue.

Really? This has happened over two sets of tires.

So if I take the fronts and swap them today that pretty much will eliminate the tires from the equation, right?