Prop Shaft support

[kevchard]

Has anyone got any pics of a prop shaft in situ? I am wondering where (if needed) to put a centre support bearing on the prop.
The prop drops down at an angle to the diff, and it goes to the left, so i am needing to have a UJ (or cush assembly) in the prop to get it all to line up. Can the bearing be fitted on the prop after the prop is on the car or does it need to some how slide onto the prop before fitting onto the car?
Can anyone suggest where i can get a bearing if i need one.
The build manual with the car leaves a bit to be desired.
It is a viper (DMS / Cobretti), with cortina running gear and granada engine (should be same principle for all props i am assuming).
Cheers for now

[wilf]

Kevin - I have yet to see a Cobra with a centre bearing on the propshaft, not that this means there isn't one out there somewhere.

Usually, the propshaft is so short - (15 inches is in the right range), that there is no need for centre support bearings.

There should be UJs at each end tho'. Just check that they do not reach any limits of deflection as you turn the shaft, with the engine/gearbox and differential as far out of line as you are going to get in normal use (i.e. engine/gearbox deflected fully on the mounts).

There must be no binding whatsoever in the propshaft as it turns.

If you are not totally sure about this, see if you can get someone local (and knowledgeable) to pop around and take a look.

[Miket]

Kev

In addition to Wilf's comments, I presume with it being Ford, the gearbox rear will terminate with a 4 bolt flange and not a spline, if so you will need the prop to have a slip joint built into it, to allow for movement between gearbox and diff. :thumb::thumb:

[kevchard]

Hi Wilf and Mike.
THe gearbox is a T5 (very simular to your big V8 boys boxes), so it has the sliding spline effort.
The diff at the back has a flange. I was worried as the prop has to drop down (toward the diff) and has to kink to the left at the diff end. I was worried that the prop may have the same probs as the steering column downshaft (eg has sideways deflection when the shaft rotates).
I am no engineer, so any help is vastly appreciated.
Engine and gearbox are back in (and never coming out again hopefully), so the rolling chassis is looking a bit happier.
Cheers for the help, but if i don't need a bearing, i am not fitting one just to make life complicated.
Luckily we have an engineering company about a mile away, so i will pay for an hours labour for them to come into my garage, and measure up for the prop. Then they can make it for me.
I already have the original 5 mile long granada diff, so a 'cut and shut' is required.
The local company do all sorts of motoring mods to older engines, so i am hoping they will accept the job. Also if they measure up wrong it is their fault and not mine :O).
Cheers for now, i have cats to feed.

[Purple AK]

Kev.

All diff flanges are offset one way or the other As said a straight prop will be fine :thumb:

[Miket]

Kev

Sorry mate should have read your signature before posting, as it does state T5. duuuuuuuuuuuuuuur.

You don't need a sliding joint in the prop then. :thumb:

[kevchard]

Thanks again.
Looks like something might be straight forward after all (now if that isn't tempting fate, nothing is).
I can't decide whether to get prop sorted now (no petrol tank, seats, bodyshell off etc), because as transmission tunnel is built into fibreglass floorpan, or to wait till near the end after the full weight of the car is on the frame.
It just seems easier at the moment to get prop measured, but trouble is all the weight of 'tother bits will change prop shaft length.

[TINKA]

As long as it is all put together correctly why is the extra weight going to change the length of the prop.

Get it now when it is easy to fit, don't forget there will be the yoke where it connects to the gear box which will allow for any slight movement once you get it on the road. :thumb:

[route66]

Originally Posted by kevchard

... but trouble is all the weight of 'tother bits will change prop shaft length.

Diff is fixed, engine / gearbox is fixed (ish) - the propshaft length will not change with weight.

Steve

[kevchard]

The axle is of the 'solid type' eg mark iii cortina with drive shafts and diff as a 1 piece assembly (eg diff is not bolted to car frame, cept by suspension arms).
When the body is dropped on the car, the springs compress and the floorpan gets lower to the floor (hence gearbox gets lower to the floor, and position of diff to gearbox spline changes).
I think that is how my head sees it working anyway.