Friday, 29 August 2008

Preparation for 2008 RBRR - driveshafts and trailing arm fiasco

It's looking unlikely (some might say impossible) that the Herald Coupe is going to be ready in time for the RBRR in October.

So instead, in contingency we have the 2000 saloon. Except that the saloon has a list of issues of it's own. Ever since I bought it back in April this year, it's had a few knocks and creaks that have been slowly getting worse. Plus the fact the rear suspension was never quite the right camber.

Preparation for 2008 RBRR - driveshafts and trailing arm fiasco

Time to get it sorted. Some new rear springs (475 lb/in² 1" lower) and a set of UJs should do the trick.

New versus old springs

My RBRR co-driver Mark Bland came to the rescue stripping and fitting the new UJs. Mark worked his way through several spare shafts as two of the yokes on mine were beyond repair.

The Reject Pile

Meanwhile I set about fitting new trailing arm bushes. (Mark suggested these were fitted in-situ to save have to split the brakes - more on that later). Getting the old bushes out was quite simple using a G clamp. Getting the new bushes in was proving to be a bit of a pain as they were slipping and sliding off the clamps. Step forward the patent pending MB/CG trailing-arm-bush-preloader.

Patent pending MB/CG trailing-arm-bush-preloader

Quite simply an off-cut of scaffold pole the same length as the bush. The inside diameter of the scaffold pole is pretty much the same as the shoulder of the trailing arm bush. A thick washer fits inside the scaffold pole.

Assembly is as follows -

1. Apply some assembly lubricant to the inside of the scaffold pole and the inside of the trailing arm.
2. Shove the bush inside the scaffold pole.
3. Align the scaffold pole, the trailing arm and suitable clamp.
4. Push through until nearly home.
5. Take a second piece of scaffold pole - only needs to be about ½" thick - on the exit side of the trailing arm to allow the bush to exit and seat fully home.

Patent pending MB/CG trailing-arm-bush-preloader

We did this on the first side lying under the car with a certain degree of success, and then Mark pointed out we could remove the trailing arms without splitting the brakes and do the whole thing on the bench! The other side took a fraction of the time using the bench vice instead of the G clamp.

Re-assembly was quite quick - in went the new 475 lb/in² springs. No plans to replace the shock absorbers for now, although they seem to be a peculiar design with a progressively wound spring incorporated around the shock. Any ideas what they are? There's no makers name on them.

Strange Shocks

Wheels back on and dropped off the axle stands the back end of the car is now sitting much better - gone is the positive camber. The ride is a lot firmer, no more wallow and no more clunky UJs.

Now just the front suspension to sort out...

(all photographs courtesy of Mark Bland)

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