An M.G. Locost Build
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July 2, 2016
Noises

On our very first drive in the M.G. Locost, almost three years ago now, we heard a couple of noises that we thought we'd fix over the course of the next few weeks. Or months. One of those noises was a repeated clunk in the rear whenever we backed up the car. It wasn't loud, and didn't seem to affect anything, and we only heard it when we backed up, so nothing to worry about. From time to time we'd crawl under the car to make sure everything was still attached, that all of the nuts and bolts were still tight, and we never found anything amiss.

  Bargain rod ends served us well but got dirty
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Three years later the clunk was still there, and sounded like it was getting worse. We even heard it occasionally in the forward gears. A recent thread on LocostUSA suggested a possible cause—suspension wear, specifically the bargain brand rod ends (a.k.a. Heim joints) we used to attach the rear trailing links to the axle back when we were trying to scrape together enough cash to get the chassis on wheels. The type of driving we do in the Locost (and, let's face it, every car we drive) had likely taken its toll on these cut-rate rod ends, particularly as they'd never seen any sort of lubricant in their lives.

We decided to do something about it, and more than just slathering on a little grease. We ordered brand new Heim joints, going all out this time because we only needed five (four trailing links and the Panhard bar), and Summit Racing has free shipping on all orders over $99. Their $20 rod ends are made out of heat-treated 4130 (chromoly) steel, which admittedly sounds pretty good but we were a little concerned that the added cost was only buying us extra strength. We didn't need extra strength, we needed extra longevity—rod ends that would never wear out.

Shiny new rod ends are much cleaner  
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So we got rod ends lined with Teflon, or one of its cheaper competitors, and not just Teflon but Teflon mixed with Kevlar. So bullet-proof. Oddly, these indestructible rod ends were a few dollars cheaper than Summit's most expensive rod ends, although still three times as much as our bargain brand rod ends. When they arrived, we could see why. They looked like something NASA would spec for a Mars lander. Every surface was machined smooth, and there was zero play in the ball. They were almost too good for our car. Okay not really. Nothing's too good for our car.

Five Summit semi-expensive rod ends only cost $90, which meant we either had to buy another $10 part or pay $15 shipping. So we got a set of screwdrivers, since we never seem to be able to find the right screwdriver when we need one, and while Summit's free-shipping promotion may have gotten us to buy something we didn't want, the good news is they only made a few bucks off the screwdrivers, and had to pay the whole $15 shipping charge themselves. So our win. Plus, the screwdrivers are actually kind of nice. We'll miss them when they start to disappear.

  Panhard rod mostly grease-free
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Changing out the rod ends was not easy, and ultimately we replaced only three of them, the three that were accessible without completely dismantling the car. Not that dismantling the car would be difficult. We did it several times during the build, and mostly on purpose. But it's not the same now. For one thing, the undercarriage is greasy. Not with ordinary grease, either, but with a grimy mix of road dirt, exhaust soot, engine oil, and other less identifiable substances. Also, many more parts are attached to the car now, some of which, like the bodywork, can't be easily removed.

Still, we started the job thinking it wouldn't be such a big deal, until we realized we'd have to pull the seats and side panels to access the forward trailing link bolts. Not a big deal if the new rod ends actually fixed the noise, but we were just guessing here. Might work, probably wouldn't. We got as far as setting the car on jack stands and unbolting the wheels, then looked at all the grease and decided to start with the Panhard rod, which looked relatively clean. The only discouraging thing, once we got it off the car, was that the rod end looked like new. Greasy, but new. Obviously the Panhard rod doesn't see much stress. No doubt the trailing links would be much worse.

Lower trailing links somewhat accessible  
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We got the rod ends off the lower trailing links by removing the 1/2" bolt that attaches them to the axle bracket, then swinging the link down and out of the bracket. Unfortunately, the trailing link rod ends didn't look a lot worse than the Panhard rod end. Almost no play in the ball, certainly not enough to cause all that racket. Of course the upper links could've been worse, but somehow we doubted it. We're not 100% sure, or even 50%, but we think the lower links do most of the job of pushing the car. If the lower links were okay, the uppers probably were too.

In any case we weren't going to get a look at the upper links without completely dismantling the car, because they don't swing out of the axle bracket the way the lower links do, because the shocks are in the way. We decided at that point we'd done enough damage for one night, having replaced three rod ends and made a mess of our clothes and hair, so we torqued everything down, rechecked the jam nuts, bolted on the rear wheels, and set the car back on the ground. Too late for a test drive, or even to put away the tools, so we took a shower and went to bed.

  Upper trailing links trapped forever by shocks
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Next morning we hopped in the car, fired it up, and braced ourselves for the clunking noise as we backed out of the garage. Incredibly, the noise was gone. Not like it was quieter, or back to normal, it was just gone. Completely gone. That had never happened before. We're not sure if it was because the cheap old rod ends were worn out, or the deluxe new rod ends are just that good. The suspension has never been this solid. Even in the forward gears, you notice it. Obviously the upper links must be fine, or good enough. How long it'll stay this way, no one knows.

We are postponing by a few weeks the frame repairs we promised we'd do after our recent encounter with a concrete median strip. We've pretty much determined that we only need to graft on two new pieces, to the ends of the LB and LC tubes. The F2 tube was only slightly deformed, and we're pretty sure we can coax it back into shape with a steel sleeve and a big C-clamp, thereby avoiding messing with the F2/LC joint, which wasn't damaged. This method of chassis straightening is not new to us, having tweaked a few frames on production cars over the years.

Paint maybe only a few molecules thick  
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The forward body panel that got mangled when the frame was crushed is ready to go back on the car. We had to strip the old rattle-can green paint off the panel, all the way down to the metal, then cover it with about six coats of high-build primer, but we finally got the surface smooth enough for a single layer of Rustoleum Hunter Green. The new paint is uncomfortably thin, barely enough to hide the primer, but we're done with the panel because the paint won't dry for weeks, or ever, and would shrivel like a grape at the slightest hint of any more paint.

The rest of the accident damage seems to be fixed. While under the car replacing rod ends, we found the spot where the floor had engaged the median strip. It's about 6" from the transmission tunnel, right in front of our Aussie floor stiffener, totally justifying our uber-heavy Aussie mods. The floor was pushed up about 1/4 inch, not noticeable from the driver's compartment because of our plush carpets and floor mats, but easily flattened with a long 2x4, a.k.a. wooden beam, and a BFH, a.k.a. hammer. As a bonus, the floor no longer oil cans when we step in the car.

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