Prop shaft Screw on Collar purpose?

[gavk]

Good morning

I've had a metallic rattle coming from the propshaft at low speed. Upon investigation this morning I found the following collar loose and undone. Threads are not damaged and I can screw it back on easily.

I just wondered what the purpose of the collar is? More specifically, is it to help hold grease in, in which case I should pack some grease down there before I reassemble?

The shoulder on the collar is only small so I cant see it will help hold much grease....

I know it's not likely to be an elan +2 part since my car is a Spyder Zetec but being car guys I thought someone on here may have seen it before?

Thanks in advance

Gavin

[gavk]

If I'm reading the following picture correctly it could be a dust cap which should have a cork gasket beneath it, anyone concur? Anyone know if that is the purpose on the Zetec propshaft?

[Chancer]

I am guessing that you have an MT75 or other gearbox with a fixed coupling like the illustration?

If so then the sliding splined joint is there because the gerabox tailshaft does not have one, it will be a gland nut which should compress some sort of seal as you surmise.

TBH a fixed length prop would be fine but for the production variances between each vehicle which would make one either too short or too long in many instances with the resultant wear and NVH it would create.

[gjz30075]

The MGB propshaft is the same. I'm fitting it to my Elan for the Lotus 5 speed conversion. With a bit of
shortening at the diff end, it works perfectly.

My MGB shaft has a felt packing of sorts and gets compressed when the collar is screwed down I'm sure
it's used to hold the grease in

[gavk]

Thankyou both for your replies.

Yes, it is a MT75.

I have reassembled for now and I will investigate the condition of the cork gasket as soon as I have a chance.

Does anyone else know if the cork is definitively used to hold grease in?

Thanks,

Gavin