Propshaft play?

[DonDP]

Good evening all,

Some of you may have seen my previous topic regarding high speed vibration at 100mph+

I am still hunting down the culprit and as mentioned I wonder if it may be propshaft related. Would anyone be able to comment if the movement in the prop shaft I have captured in the video link below is normal.

Its a S3 Metric car, Mazda box, BMW diff.

[Jim 123]

Due to the camera angle it's hard to see if it is the female splined end of the shaft that is moving because of fit over the tailshaft or is the U/J yoke causing the movement.  Have you greased the propshaft joints using the nipples?

[DonDP]

Thanks Jim,

it does seem that the female spline is moving over the tailshaft but it moves more when the propshaft is in a certain orientation - is this normal?

I greased them this morning but not sure when they were last done, only had the car since January!

[Jim 123]

When I did my build I packed the inner splines of the propshaft with grease, but that was more a precaution against driveline clunk coming on and off throttle.  I did not look at the condition you are observing when I was building, but it may not be untypical and I haven't done too much driving at the 100+ speeds where you are encountering the vibration. If you look at the video 42 sec in, it looks like circlip holding the bearing cup might not be original and is bent.  Not a solution but perhaps an indication of some earlier work on the shaft, or just a trick of the camera.

[SM25T]

There is definitely something going on in there.

[DonDP]

Thanks both, and good spot there eagle eyed Jim! That circlip is definitely odd!

Think I am just going to order a new one, by the time I have this one off, drive up to Baily Morris and back twice its not a huge saving getting it rebuilt. 

Caterham have them in stock and will drop Chris a note @ Redline but is there anywhere else I should try for the part?

[RFF]

i think it would be prudent to remove the prop and then you can inspect the joints correctly,

If the UJ parts company with the yoke you stand a very high chance of being injured.

Is your car fitted with a catch loop which is meant to limits the props trajectory if it lets go,

 

[DonDP]

Quick update, prop shaft ordered, going to replace it next week. 

No catch loop that I can see on the prop, are these a standard part or does it require fabrication?

[Jim 123]

Might be worth checking if the gearbox output shaft bearing has suffered when you swap the prop.
 

[DonDP]

Thanks Jim, any tips for checking it?