DIRTY STUFF

GEARBOXES: essential assemblies to change the speed of your vehicle. Nineteen-fifties stuff got away with three forward ratios – except for Pommy imports and little light cars from Europe, which generally boasted four forward gears to suit their higher-revving engines. So Holdens had three in their small American-style case, sidevalve Ford V8s had a similar set-up, and Uk-sourced Ford Zephyrs also went down that same engineering road.

At about that time, I was an apprentice at a successful Ford dealership, working on stuff like the dreadful fall-over Prefects, which suffered from inbuilt clutch shudder so severe that all the body bolts fell out on the road.

At that stage, we were selling Ford’s later 100E Prefects, which came with inbuilt terminal rust, and the MKII six-cylinder Zephyrs. So when these okay cars, wagons and utes began breaking their three-speed gearboxes, we had a good look into their internals to figure out why.

Ford UK had made a cost-cutting decision to retain the rear output-shaft ball-bearing with a fairly fat internal circlip, which was never going to be man enough for Oz conditions. But there was a way to stop this nonsense and save the cast-iron rear extension housing.

We gave that to our machine shop, who faced off the front bit down to the rear of the circlip groove, drilled and tapped three holes to take 5/16in UNC bolts, and gave these bits back to us with a 6mm-thick, doughnut-shaped flat steel plate that bolted to this new face. The idea was that this new plate would retain the output-shaft bearing instead of that hopeless circlip, thus resolving the breakage problem. It was a tad difficult to fit the plate and bolts, but this mod worked brilliantly and I never got one back.

FX-EH Holdens were also known to have problems with their three-slot cogboxes. They had a nasty habit of destroying their single-row ball-bearing that supported the output shaft at the rear of the main case, which really worried first and reverse sliding gear and stuffed up the cluster. Some clever Aussie engineer figured out that it was possible to replace this failing single-row bearing with a double-row heavyduty piece, using a short tube spacer butting against the speedo-drive front circlip to lock in this fatter bearing.

So Holden products were not immune to gearbox failure, as happened with the later sixcylinder HR, HK-HG and Torana offerings, when they were fitted with the German-sourced, fourslot Opel cogboxes. The problem was that these lightweight transmissions had been designed to fit behind the four-cylinder Opel engines, but Holden’s think-tank were desperate to find a four-speed ’box they could offer as a sporting option behind their red six. The red motor made a heap more horses than the Opel four, which came out of a lighter bodyshell assembly, so, of course, GM-H engineers should have expected that this imported ’box would eventually fail. Which it did, when the undersize cluster rollers working on an undersize shaft gave up the struggle. The needle rollers died, took out the cluster shaft and chewed all hell out of the rollerbearing bore of the cluster gear. And new Opel cluster gears were damn expensive.

There was a fix. Somebody remembered that Henry’s flathead Ford V8 cars from 1932 onwards spun their cluster gears on fat bronze bushes, and these about lasted the life of the car. So if you bought a cheap new cluster shaft, machined out the roller wear inside the cluster and turned up bronze bushes to suit, the Opel boxes were revived and reliable again. So long as you didn’t rev the ring out of the red six engine in the lower gears!

In the mid-1950s, Ford Australia was under heavy leverage by Ford UK to begin manufacturing the MKIII Zephyr in Australia. But Charles A Smith, the new American CEO, did not like the UK Zephyr. Charles told me that on a visit to Ford America, he was shown the new and top-secret compact car, the Falcon. Charles said: “That’s the car I want for Australia,” and pressured the US decisionmakers until they gave in, and that’s how the XK Falcon came to be made in Oz. And it didn’t suffer from gearbox problems!

THE RED MOTOR MADE A HEAP MORE HORSES THAN THE OPEL FOUR, SO GM-H ENGINEERS SHOULD HAVE EXPECTED THE IMPORTED ’BOX WOULD EVENTUALLY FAIL. WHICH IT DID