W123 alignment specifications

[rocket88]

Can anyone refer me to W123 caster, camber and toe in specs?

thanks in advance

[whunter]

Chassis: wheel alignment spec
Chassis: wheel alignment spec






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[rocket88]

that page has 17 entries, none of which simply showed the three numbers

caster
camber
toe in

[Stretch]

I've got that info for you:-

W123 Caster / castor settings for a sedan / saloon?

Also take a look at this of you fancy doing it yourself!

How I adjusted the toe in / out, camber and caster on my W123 300D

[rocket88]

Indeed I do intend to do it myself.

A friend accustomed to restoring cars down to cleaning the frame until you could eat off it replaced all the front end parts of his MB, then took it to a local high end alignment shop, they do racing cars etc,

They got it up on the rack then reported to him he needs all new front end parts.

Originally Posted by Army

I've got that info for you:-

W123 Caster / castor settings for a sedan / saloon?

Also take a look at this of you fancy doing it yourself!

How I adjusted the toe in / out, camber and caster on my W123 300D

[rocket88]

Great info Army, I intend to use it after renew of ball joints and perhaps control arm bushings. Haven't figured out how to asses control arm bushings, ball joints and tie rod, drag link are clearly shot, visible play.

What do you think about this "bubble stick" ie level with digital degrees reading out to .1 degree of deviation from vertical or level?? Looks perfect for camber.

Is it impossible to simply determine the strait line through each ball joint then measure its deviation from vertical to adjust caster??

http://www.harborfreight.com/16-inch-digital-angle-level-65451.html

Originally Posted by Army

I've got that info for you:-

W123 Caster / castor settings for a sedan / saloon?

Also take a look at this of you fancy doing it yourself!

How I adjusted the toe in / out, camber and caster on my W123 300D

[Stretch]

There's a W123 front suspension rebuild DIY here:-

http://www.peachparts.com/Wikka/W123FrontSuspension

If you want a trick to fit in the LCA bushings have a look here:-

How I ended up fitting the bushings to my W123 300D LCA

To measure castor directly you need to get hold of a factory tool - this is a smarty pants piece of kit that measures camber and caster in one. It takes its reference points from the ends of certain ball joints. Check out the FSM. If you can get hold of one of these bits of kit you'll save yourself lots of time.

If like me you couldn't get hold of one of the smarty pants factory tools then you need to do the turn the wheel by 20 degrees trick that I went through (How I adjusted the toe in / out, camber and caster on my W123 300D). You measure the camber and add the absolute values to get the caster measurement. This is by no way a quick method! But if you use a home made camber gauge you can make the plumb bob line as long as you like to get a very much more accurate measurement than any fool with a laser will!

Despite being a fan of the home made camber gauge - the $25 0.1 degree accuracy spirit level from harbor freight looks like an easy way of doing it. You'll probably have to find a way of getting it to fit on the rim nicely though - space it with wood / bolts (threads) etc etc

EDIT:-

I've now got a good way of measuring the spreader bar force - I'll try and rig up a picture of it tomorrow and add it to the thread I made.

[rocket88]

Caster is the degrees off vertical of a plane that passes through the center of both the top and bottom ball joints with wheels strait ahead. Right?

Seems to me it ought to be easy to find that plane reasonably accurately without a fancy gizmo. Even by eyeball.... using the digital spirit level to adjust to spec.

I gather the european FSM is more complete than the one sold here in the states. More than one forum member from the Netherlands has provided specific information from their FSM (in German?) that has much greater detail ..... and also cited files that do not appear at all in the CD ROM discs I have for W123.

For example: nothing at all is provided about specifications for front end alignment ..... or transmission dismantle and assembly for the 716.2 series 4 speed manual. I'm scrounging around using an after market preceedure for the 5 speed transmission of the same era which will probably serve the purpose but .... it would be nice if they were more complete here.

Originally Posted by Army

To measure castor directly you need to get hold of a factory tool - this is a smarty pants piece of kit that measures camber and caster in one. It takes its reference points from the ends of certain ball joints. Check out the FSM. If you can get hold of one of these bits of kit you'll save yourself lots of time.

.

[Stretch]

Originally Posted by rocket88

Caster is the degrees off vertical of a plane that passes through the center of both the top and bottom ball joints with wheels strait ahead. Right?

Seems to me it ought to be easy to find that plane reasonably accurately without a fancy gizmo. Even by eyeball.... using the digital spirit level to adjust to spec.

I gather the european FSM is more complete than the one sold here in the states. More than one forum member from the Netherlands has provided specific information from their FSM (in German?) that has much greater detail ..... and also cited files that do not appear at all in the CD ROM discs I have for W123.

For example: nothing at all is provided about specifications for front end alignment ..... or transmission dismantle and assembly for the 716.2 series 4 speed manual. I'm scrounging around using an after market preceedure for the 5 speed transmission of the same era which will probably serve the purpose but .... it would be nice if they were more complete here.

I thought caster would be relatively easy to measure too. I lost confidence when I crawled under there and took a look at it though. I don't think you can measure it accurately with the wheels in the straight ahead position without the special tool - but hey be a pioneer - please let me know how you get on.

As for the FSM - from what I can make out there seems to be a big difference between the paper copies and the CD version(s). There are loads of people selling the German version here on CD - I haven't coughed up the money for one of these yet... I might do - but then again I might not. However if you need a link let me know.

[rocket88]

Originally Posted by Stretch

I've got that info for you:-

PeachParts Mercedes ShopForum - View Single Post - W123 Caster / castor settings for a sedan / saloon?

Also take a look at this of you fancy doing it yourself!

How I adjusted the toe in / out, camber and caster on my W123 300D - PeachParts Mercedes ShopForum

After destroying a set of Michelin tires I got my 84 300TD on a professional rack, the tech seems good and I determined it was not alignable. Apparently an accident in the past pushed things out of shape.

It had a full degree of postitive camber on one side even with the adjustment maxed out.

Getting it on a frame straitening machine in a body shop would cost a fortune, the one shop I spoke with would not even touch it except within the context of a total collision repair.

I took the lower control arm out and modified the slot allowing the eccentric bolt greater adjustment. Used a die grinder and burr.

I also took the upper control arm out and made its mounting hole in the fender into a slot allowing a little adjustment where there had been none before. In that way I got the camber within the MB factory specs. With more fuss I could get it perfect dead 0 degrees.

Every camber adjust throws toe into left field, so you have to zero toe again it even before determining what the camber adjustment did. Its finnicky. Back and forth.

The caster is tough without a commercial rack. Thanks to you Stretch for the 20 degree each direction routine .... my alignment tech swings the wheels each way thru the 20 degree position first thing when it is all set up ..... no doubt the machine captures camber at each turned position, the sums the caster at each position for each wheel. .

At home It is difficlult to get precision with those camber measurments at each 20 degree turn positioin .... In strait ahead position its easy enough, A simple carperters spirit level is good. Guess that is why aligment racks and lasers exist. You need it to a fraction of a degree.

[Stretch]

I'm glad to hear you got a solution after all this time!

[BillGrissom]

Toe-in is most important. Ideally, you want the two front tires exactly parallel when driving. You adjust slight toe-in since the wheels are pushed back in driving. M-B specs to use a pre-loading rod to take up most of the gap before adjustment.

Camber has to be pretty far off before radial tires wear due to it. Definitely enough to see with your eyes. Racers adjust with the tops leaning in significantly, to take corners harder. Look at Indy cars head-in, but they don't care about tire wear.

Caster is more of a personal preference. Ease of turning the wheel vs car wanting to track.

[Charlie Foxtrot]

My early 80's Chilton's (professional labor guide) shows most 77-81 W123s as having suggested specs:
Camber: 0 degrees +/-10' (minutes)
Caster: (power steering) 8 degrees 45' /-30'
Toe in: 0.08" to 0.16" (1/16" to 1/8" toe in)

Typically in the 80's we tried to tailor the alignment to the type of road crown (hi crown vs no crown). For example, highway driving (freeway/expressway had little crown) we'd go for 0 camber and very slightly stagger the caster left slightly less than right with an 1/8th inch toe in. Hi crown roads such as rural two lane section roads got L +1/2 degree camber with the R at 0; caster staggered left 1/2 degree less than right with an 1/8th inch toe in. The left camber and caster were adjusted to overcome crown issues regarding wear and pull/drift. All this assumes proper ride height (no sagging springs), tires in good condition, properly inflated and no frame damage. In situations such as you describe, we used 'offset' bolts & ball joints to try and compensate for minor frame deflection. If it was too great, we'd put it on a frame puller and try to pull it straight. Sometimes we'd find a unibody (like MBs) with one frame stub bent up. Those were an extreme challenge. Use extreme care when doing a pull - don't bend the sheet metal. BTW you always need to swing the wheel 20 degrees in & out in order to accurately check caster. Its the only way you'll catch 'set back' (bent spindle). Good luck!

[NoSparkNeeded]

I had both my cars set up by the dealer. Both wear on the outside front tires.
What setting needs adjusting please? I let the dealer do it at increased cost
for a reason I read here, something about a "spreader"?? whunter posted
something years ago about that. What should I tell the mechanic about outer
front tire wear? Do I need to rebuild the front ends?

[BillGrissom]

I would first verify toe-in. With a helper, use a tape measure to measure across the front tires fwd & aft sides. Fwd track should be 1/16 to 1/8" less than aft (without a spreader bar). Even quicker check is to lay a 4" straight edge along the front wheel and sight at the rears. You should sight ~1/2" off the rear on both sides, with the steering centered. FWD is easier because your sightline should fall on the rear tire.

But, whenever I had wear due to excessive toe-in, the inside edge of the tires wore. Toe-out cause wander, so doubt you have that. Your problem may be excessive positive camber, i.e. tires leaning out at the top. Should be very visible.