Suspicious vibration - prop shaft needs balancing?
Posted By : Mark Hammond, 25-Jun-2007, 04:58pm
Sounds likely that it is the prop as vibrations usually are present at a certain speed and then again at the same speed doubled, ie 40MPH and then
80MPH. You could try the old fashioned way with a big jubilee clip, but I'd send it to a specialist propshaft rebuilder for
evaluation/rebuilding/balancing.
Mark
Mark
Suspicious vibration - prop shaft needs balancing?
Posted By : Chris Taylor, 25-Jun-2007, 06:34pm
Classic symptoms of propshaft vibration. It MIGHT just be the u/js going (they will deteriorate rapidly!) or it could be balance. The issue about end
to end fitment is, I believe, a red herring. Either way round will do.
It IS feasible to balance yourself in situ with big jubilee clips, but it takes patience and is a potentially anxious process revving up the whole drivetrain to 80mph with rear on axle stands (wheels OFF the car!). You need TWO jubilee clips for each end of the propshaft by the way. The process is a little involved. Let me known if you want to tackle it and I will try to describe it simply. But first try sourcing the BIG clips needed.
By the sounds of it, you have a splined propshaft. It's possible there is play there, in which case, you may need a new shaft, or at least a new splined end welding on. A specialist propshaft recon company is your best bet.
Before resorting to that though, it's just worth checking that the DPO has made sure that all four bolts holding the propshaft onto the flange (at each end) are identical, and so are the nuts. One bolt of different length (and therefore weight) might just throw the balance out as these cars are quite sensitive to propshaft balance.
If you do balance the shaft on the car (or have it done) make sure you mark the flange of shaft and gearbox/diff so it can always be reassembled in that position.
It IS feasible to balance yourself in situ with big jubilee clips, but it takes patience and is a potentially anxious process revving up the whole drivetrain to 80mph with rear on axle stands (wheels OFF the car!). You need TWO jubilee clips for each end of the propshaft by the way. The process is a little involved. Let me known if you want to tackle it and I will try to describe it simply. But first try sourcing the BIG clips needed.
By the sounds of it, you have a splined propshaft. It's possible there is play there, in which case, you may need a new shaft, or at least a new splined end welding on. A specialist propshaft recon company is your best bet.
Before resorting to that though, it's just worth checking that the DPO has made sure that all four bolts holding the propshaft onto the flange (at each end) are identical, and so are the nuts. One bolt of different length (and therefore weight) might just throw the balance out as these cars are quite sensitive to propshaft balance.
If you do balance the shaft on the car (or have it done) make sure you mark the flange of shaft and gearbox/diff so it can always be reassembled in that position.
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Suspicious vibration - prop shaft needs balancing?
Posted By : Ian Grimstead, 25-Jun-2007, 08:26pm
Hi chaps,
Thanks for the info - I think I shall bottle it & get someone to fix it who knows what they're doing, as the thought of 80 mph and the propshaft have a problem...
)
I'll give South Wales Propshafts a go & see what they can do.
Cheers!
Ian