Staff Car Sagas

TR7 gets all the bushes, but still the vibes are not good

All the latest project news direct from the PC workshop.

I’ve been under a TR7 for most of this week. During the run around Britain last year I noticed, along with the regular bouts of overheating and coolant loss, an unpleasant clonking from the rear end and uncomfortable vibration underneath.

A knackered gearbox mount and squigged, hardened bushes all round had me on the phone to Robsport for the mount and Polybush for the TR7 bush kit. Everything turned up within a couple of days and I was off to the PC workshop for some down-under fettling.

The Triumph gave up its rubber without complaint and, to be honest, once pressed out, the old bushes didn’t look too bad, low mileage and little use having preserved their shape. However, age meant that while the bushes were in original condition visually, they were hard between finger and thumb. Pressing the new bushes in was easy too. Having cleaned the various mounts and holes up carefully they took little persuasion to fill their respective apertures. I used the Polybush

Dynamic range coloured Orange. A bit like me in my Twenties, they provide a decent balance between stiffness and elasticity, strong but smooth. It took about six hours for Matt Tomkins and I to do the entire car and it was a job worth doing. The clonking disappeared and the road noise too. But the new bushes also highlighted the vibration coming through the drivetrain. Next job, fit gearbox mount. The old one had ceased to be effective through complete disintegration. Contaminated with oil and almost entirely without shape, the new mount actually raised the ’box by half an inch. But on the road it transmitted the vibration even more effectively. Sigh. I checked the prop. The

rear CV joint was clunky and had movement. A secondhand item cost me £35. Disappointment – the vibration was still there (quite intense above 50mph), but slightly different. I began to think about the rear axle. I didn’t want to, because a replacement will be extremely expensive, but all the fingers of doom are pointing in that direction. First I will try running the car with a different set of wheels.

Still, my little wedge now has an MOT certificate and is ready for the year. It seems to be behaving itself on the cooling front as well although I will wait until the searing heat of a British summer before I decide it is cured. Annoying. I want this classic to be my daily driver but on this form it will spend more time off the road than on it. Anyone got a well-balanced set of wheels I can test?

Polybush does the complete kit. Orange = Dynamic.

Will Danny cure his vibrating rear end? MOT first, then out on the road for a test.

New bush kit laid out, with cleaned TR7 parts. Polybush diagram helped.

Cleaning the old componentry.

Old bushes were hard as ‘wood’.