Friday, June 15, 2018

Beck TD, Part 26: Beck Gets an Alignment

From the very first day that I saw Beck, I knew there was an "elephant in the room." Even though Beck TD is astonishingly rust-free for a 66 year old car, and had solid woodwork and other fitments, there was one place where Beck had seen a hit. It was dead center in the front crossmember, and it was quite a hit:


I would love to know exactly how that happened! It's as if somebody hit a high curb or maybe a stump. Anyway, I suspected it would have an effect on the steering, and once I drove Beck a bit, my suspicions increased. The steering is tight and precise, but it doesn't return to center on its own after a turn. That is usually a problem with the "caster" alignment, and caster is often affected with frame damage.

There are three main alignment settings for a front end. Caster is the angle of steering axis as viewed from the side of the vehicle. Camber is the amount the wheels lean in at the top, and toe-in is the deviation of the wheels from "pointed straight ahead." Only toe-in is adjustable on a TD. When we rebuilt the front suspension, I set the toe-in to zero (the factory spec) using long straightedges and a tape measure, but it needed more precise equipment to get exactly right. 

Thanks to a member of the Volvo Engined MGs Group on Yahoo for correcting my earlier definition of caster. What I had described was actually "kingpin inclination," which is the angle of steering axis viewed from front to rear.

Today, I took Beck over to my friends at Lancaster Mitsubishi. They measured and the minimum track width (the distance between the inside of the front tires) on their equipment was 40 inches. We then measured Beck, and the distance was... 40 inches! Beck is literally the smallest car that will fit. And it did fit, tires squeaking a bit as the rubbed on the guide:


The initial alignment showed that I got the toe-in (the bottom row on the screen) pretty good - about 1/3 of a degree off on each side:


The tech was able to get it perfect:


The top row of numbers is the camber, and it's within spec also. The middle is the caster, and that is not good news. The spec is 4 degrees, plus or minus 0.5 degree. The left is a little out, and the right is waaaay out. Clearly, that big hit moved things around a bit.

I'll return Beck to the Lancaster Mitsubishi body shop in about a week for further diagnosis. The options I know about are using a frame machine to push things back into place, offset bushings to modify alignment, and slotting the mounting holes so that there is room for adjustment. We'll see how it turns out, and I look forward to a better-driving Beck TD!



1 comment:

  1. emery, something else to consider...when i had the car -- with the old rack -- i never had that problem with the steering -- and if i did, i didn't notice it...when i made that massive parts investment from Moss, i bought a new rack because they gave me such a good discount on everything else -- shocks, springs, et al...as you know it's a sealed unit that's is made in Argentina -- an odd place...anyway, you might want to think about something wrong in the new rack...as you know, there's not much to them but who knows...so, my point is it might be worth putting the old rack back on and see if that fixes the problem before you try a more expensive fix...i have had, in past, some issues with component quality from Moss...i recall buying MGB brake and clutch master cylinders (supposedly brand new) that just wouldn't work correctly...for your consideration. good luck, mark

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