Would You Believe?
by Ken Gillanders

Any Triumph mechanic with more than five years experience or so has probably seen just about any trick the car can pull. However, every so often something new comes along. Gerald Mohr had a winner. He called BFE one day and recounted the following story. He had overhauled his gearbox a year earlier to cure a mournful howl. While doing the job he had found the nose of the input shaft had broken through the case hardening. As this is also the inner race of the central bearing, he checked the roller bearing and outer race surface inside the 1st motion shaft; all OK. He bought a new output shaft and reassembled the gearbox. It worked fine. About a month later he noticed a pool of oil on the driveway. He jacked up the car and found that one of the gearbox tailshaft housing bolts was gone, and the others had backed out as much as three turns. He pulled the gearbox, coated each bolt with "Stud Lock," cleaned all the holes, then drilled and safety-wired the bolts. In the gearbox went, and no sign of trouble. Several more months went by and, lo and behold, another pool in the driveway. By now he was furious. He pulled the gearbox again and found the safety-wired bolts backing out and the threaded holes in the alloy tail housing case looking completely thrashed. He had the driveshaft checked for balance and straightness. This was when he called me. We talked about the problem for about two hours, and frankly I had no answers as to the cause. He was about to send the casing in for Helicoils in the damaged holes, which were badly needed. I mentioned this problem all seemed to start after that first rebuild when he had replaced only the output shaft... why not have that new shaft run between centers to see if there was a problem of some kind. He acted on this advice and had it checked, where he found that the new shaft was .004" out of true and indeed the cause of all this trouble. What a blinding piece of luck.