Apart from a mini restoration that I did in 2007 for my daughters wedding, which I will cover later in a dedicated posting, the car has undergone two substantial repairs. The first being universal joint housing / gear box main shaft in 1981 and a replacement set of gears in 1986.
Universal Joint Housing / Gear Box Main Shaft. 1981
In early 1981, I became aware of a noise and vibration coming from the gearbox and universal joint area. I went through all the normal checks, such as making sure the uni was lubricated, checked the uni housing, then the uni joint itself for any loose nuts, all seemed ok. The only hint to what was
causing the noise was in the beginning it would change pitch and sometimes momentarily disappear when the car went over bumps or was loaded up with passengers. Unfortunately I was not in touch with the car enough to realize the clue that was right in front of my nose. Anyway I pushed on regardless and was determined to fix the bloody thing.
I then decided that it must be the uni joint. I did not really know, but it seemed like a good place to start. There were slight scars on the uni joint body and inside the torque tube bell that may have been recently made, or could have been there for years. I replaced joint after joint one, two, three and four in quick succession. Each test drive ended in frustration as things were quiet for a mile or two, then the noise and vibration started again. That was the second clue that I did not recognize. I then got a
bee in my bonnet that the uni body was hitting the inside of the torque tube bell, so I ground down the uni body, re-assembled, went for a test drive, perfect, then the same problem, same noise.
So, no machine is going to beat me. It was time to get serious.
God I wish there had of been a Chev web site back then.
Dropped the tail shaft , checked the bushing, all was ok. took the top off the transmission, and after a lot of cleaning and de-greasing, discovered play between the input and lay shafts. Removed the uni joint, stripped the uni housing from the back of the transmission, and was able to pull out the lay shaft through the rear of the box, and the sliding gears through the top. Unfortunately for me I would become an expert at this as I did it many times over the next few weeks. Replaced the bushing between the input and lay shaft, re-assembled, test drive, same again, again and again. I reckon I must have replaced that input shaft bushing 3 times before I said enough, walked away, locked the bloody thing in the garage and got involved with my new baby son Ross, who was about 8 months old. At the same time we were in the process of building a new home in The Basin, so it was convenient to forget about the car for a few months. During the process of selling the old house, renting for a few months, and building a new house, the Chev was banished to where I worked in Cheltenham, on the back of a a tow truck I should mention. It was quite handy, being indoor storage in a publishers warehouse, right in the middle of the car section. Became a talking point, but to me at the time, I was over it.
So let's skip forward about 6 months, the house is finished, the garage is ready for the car, and I have finally got the motivation to bring it home. This time on the back of a tandem trailer. A burn up and down the street, noise is still there of course, so lock it in the garage and get on with the new house.
We must now be getting into early 1982 when I raise the motivation level enough to tackle the beast one more time. At the same time I was also seeking advice from others about changing the whole gearbox and tail shaft to a more modern configuration, as I could not see any light at the end of the tunnel. Luckily someone, cant remember who it was, talked me out of it.
So it's here we go again, strip out the box, change the bush, and the rear bearing for good measure, reassemble and go for a test drive, this time up to see my friend Les in The Basin. Half way up the mountain, bloody hell, noise, vibration, you know the story by now. Pull up at Les's place muttering obscenities and both shaking our heads from side to side like a pair of puppets. We are both standing at the rear of the car, with one leg on the back of the tank. No, we were not going to push it into the creek next to Les's place, but who knows? I made some comment about getting this heap of crap home and for reasons unknown climbed on to the back of the petrol tank holding on to the spare tyre, and began bouncing up and down. There was only one problem, the bugger was not bouncing up and down.
*********** BINGO ***********
The first thing I did was to loosen off the uni joint bell housing retainer from the rear of the gear box. This got me home and for several test drives with no noise or vibration.
The problem was caused by two things.
Firstly there was a scar on the torque tube where it goes into the uni joint bell housing. This was fouling with the housing and preventing the torque tube sliding in and out when the rear axle moved up and down over bumps.
The end result of the two causes was that when the car went over a bump and the rear axle moved up and down, the torque tube was pushing upwards on the rear of the gear box.
The problem was easily fixed by welding and grinding the scar on the torque tube back to a smooth finish and fitting the right thickness of gasket to allow the bell to move freely.
Was the problem fixed forever? YES.
Did I learn something from it? YES. Look for clues as to whats causing the problem.
The first clue was - "In the beginning the noise would change pitch and sometimes momentarily disappear when the car went over bumps or was loaded up with passengers"
The second clue was - "Things were quiet for a mile or two, then the noise and vibration started again".
Replacement Transmission Gears - 1986
So here we are in 1986, give or take a year. Hey, I can't remember all the dates. Anyway, when the car was restored, I took 2 calculated risks. The first was a mix matched crown wheel and pinion in the differential. The pinion was from an Adelaide 28 car, and the crown wheel was from the 27 wreck, that my brother in law Colin Bright and I pulled out of a creek at Avonsleigh. Well,we didn't really pull it out, as we watched a farmer do it with a tractor. But we watched and money changed hands, so that's close enough. The crown wheel was actually under water, but with enough greasy oil and muck on it to be fully protected, except a couple of pitted teeth. Put it back together, new bearings etc. Set it up as good as I could and ran the bloody thing untouched from 1972 up to 2007 with out even an oil change. All the old timers said the chance of a non-matched crown wheel and pinion working was very, very slim, and that any noise would gradually get worse and ka boom. Well there was no ka boom, and the noise gradually faded away, or did it blur into all the other noises? Guess that's one for me.
After that long winded explanation of my first calculated risk, let me tell you about the second, which did not work. In 1972, being very green and not having unlimited funds for the project, I rebuilt the gearbox with all new bearings and selected the best, or should I say the least worn gears from the 5 boxes I had. Although I ran this box from 72 until 86, it was obvious that the gears were never going to "bed in" and over this period the gear noise steadily increased. What did I know about case hardening? Not much, but once it,s gone, well, speak up a bit, what's that, I cant hear you!
So I got around it by doing what a few more guys are doing now, short shift the bugger. Get out of first as quick as you can, don't over rev it in second, and again get into top as soon as you can, as that's a direct drive. Well this worked fine for many years until the short shifting was wearing me out more than the gears.
The series of events that happened next are a bit blurry, but it went something like this. I was talking to a truck driver at work one day, who knew a mate from Sydney who knew a Chev parts dealer in Sydney that had a compete set of Chev 4 gears (1916 - 1928). No e-mail in those days just word of mouth and Telecom. Believing this would not have legs I ring the Chev parts guy, and bingo, he does have them.Within the hour I am at the bank withdrawing $550 to give to the mate of a mate who was driving to Sydney that night and would pick them up for me on the way back. Very trusting of me, don't you think?
The next afternoon, Friday, the word comes through from one truckie to another that the gears are on board, and will be back in the morning, Saturday. The driver lived in Tecoma, up in the Dandenongs, and it was a cold frosty morning with me pacing up and down the street as he pulled up. I grab my gears, give him about $30 for his trouble and I'm on my way home.
That set of gears, complete, still had the GMH stamp on the lead seal that secured the wire strapping. To me it was like digging up buried treasure, and even though I have since sourced nearly another complete set on eBay, plus several very good used sets, there was nothing like the feeling of satisfaction that weekend after putting a brand new set of gears into what was then a 58 year old gear box.
Needless to say, no more short shifting, first gear a lot quieter, second gear still a bit noisy as they all are, and top gear fine. I can even rev it out to about 30 to 35mph these days if I'm feeling lucky.
That's enough about repairs, we won't talk about them again until 2007. Let me tell you in the next posting about the only 2 times in 38 years that the car broke down and had to be towed home.
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