Drivetrain noise & vibration

[AG205]

Hope some can help with this because I'm running out of ideas.

I've got a 318 with a M20B25 conversion which was running fine until I put it back on the road again after a year or so off the road. Ever since I started driving it again I've had drivetrain noise mostly from the rear & some vibration at speed. I changed the guibo, centre bearing & centre mount on the prop & got it rebalanced but still no change. I swapped the diff a while back as well as that was my first thought and that made no difference either

The only thing I've noticed recently is some bearing noise from the gearbox on idle. All the conversion parts; engine, box, driveshafts, prop etc are from a 1987 tech1 sport so not surprised if they're getting a bit long in the tooth.

Any help would be appreciated as this is ruining the driving experience a bit.

Cheers

[Brianmoooore]

Gearbox rattle at idle on the 260 box is so common as to be considered normal, but doesn't cause vibration.
Checked the locating bush for the prop. centre spigot into the gearbox output shaft?
Badly worn driveshaft?
Handbrake shoes adrift (if you have rear discs)?

[AG205]

Cheers for the reply Brian.

Yeah I've had bearing noise from the gearbox on previous cars so I'm not especially worried about that. I did a bit of a search and it seems vibration from aging props etc is pretty common. When I took the prop off & felt the UJs I thought they were a bit notchy but when I took it to the balancing place they seemed to think that it wasn't a concern. The prop itself looked in good condition.

Must admit I haven't renewed either the spigot bearing or centring bush on this car, or gearbox mounts for that matter. These are basically the only things that haven't been changed!!

I was also wondering about driveshafts as they're original 1987 ones but not sure how to test them.

Also I'll check the rear handbrake shoes too.

One guy I spoke to seemed to think that I may have flat spots on the tyres as it had been sat in one position for so long but not totally convinced about that yet.

Considering it's a pretty basic car I seem to be having trouble tracking this problem down.