Fabric Joint Propshaft Lengths

[Douglas Alderson]

Hi All

Having discovered our propshaft was the wrong length in that it was lock solid between the fabric joint and the rear flange I did a bit of investigation as I was under the impression there were only two lengths long and short for the the long and short chassis.  I discovered that there is a long one for the long wheel base and three for the short wheel base cars.  The below is from the Austin Handbooks and the Austin Index Pages ref to the A7 Companion for info.

1926 Handbook 353j Propshaft Part BP28 Three speed box speedo on pulley, Type 1 axle (A7 Companion).
1928 Handbook 353w Propshaft Part BP28 and BP73 speedo on back of three speed box (I guess shorted due to longer gear box), Type 1 axle (A7 Companion).
1930 Handbook 670c Propshaft Part BP73 speedo on back of gearbox, Type 2 axle (A7 Companion)
1931 Handbook 670d Propshaft Part BP93 Increased length due to torque tube change in axle type (this is noted in the index pages), Type 3 axle (A7 Companion).
1932 Handbook 888 Propshaft Part BP93 and BP118 the latter for the long wheel base cars, Type 3 axle (A7 Companion)
1932 Handbook 888a Propshaft Part BP118 long wheel base cars, Type 4 axle “D” (A7 Companion)

       

Measuring from the fabric end of the propshaft to the middle of the cardan pin I believe the order is as follows.

BP28 original propshaft 20"
BP73 reduced for speedo on rear of gearbox 19.5"
BP93 does anyone know what this propshaft measures?
BP118 26".

We now have the correct propshaft but curious as to the length of BP93.
Thanks

Douglas

[dickie65]

I have seen cut and shut propshafts with the fabric coupling.
I might still have one in the junkshed.

[Tony Press]

Having discovered our propshaft was the wrong length in that it was lock solid between the fabric joint and the rear flange I did a bit of investigation as I was under the impression there were only two lengths long and short for the the long and short chassis.  I discovered that there is a long one for the long wheel base and three for the short wheel base cars.  The below is from the Austin Handbooks and the Austin Index Pages ref to the A7 Companion for info.

1926 Handbook 353j Propshaft Part BP28 Three speed box speedo on pulley, Type 1 axle (A7 Companion).
1928 Handbook 353w Propshaft Part BP28 and BP73 speedo on back of three speed box (I guess shorted due to longer gear box), Type 1 axle (A7 Companion).
1930 Handbook 670c Propshaft Part BP73 speedo on back of gearbox, Type 2 axle (A7 Companion)
1931 Handbook 670d Propshaft Part BP93 Increased length due to torque tube change in axle type (this is noted in the index pages), Type 3 axle (A7 Companion).
1932 Handbook 888 Propshaft Part BP93 and BP118 the latter for the long wheel base cars, Type 3 axle (A7 Companion)
1932 Handbook 888a Propshaft Part BP118 long wheel base cars, Type 4 axle “D” (A7 Companion)

Measuring from the fabric end of the propshaft to the middle of the cardan pin I believe the order is as follows.
BP28 original propshaft 20"
BP73 reduced for speedo on rear of gearbox 19.5"
BP93 does anyone know what this propshaft measures?
BP118 not measured this one but a lot longer.

Now that is interesting- the card shows the 'double ball' type Tail Shaft to 1923 - which is also shown in the 1925 'List of Spare Parts' as BP 30 alongside the later BP 1 (sliding pot rear UJ) and the newest BP 28 (fabric front UJ)

I wonder how long it took them to work out that the tail shaft needed to change length as the rear axle moved up and down !

BP 30 must have done the gearbox some damage.

Sorry- no help with the later shaft length.

Cheers, Tony.

[Douglas Alderson]

Does any one know the length of the PB93 propshaft?

thanks

[DavidK]

Measured the propshaft from my 1931 RM Box (should be BP93) it is 19.5 ins.

[Douglas Alderson]

Measured the propshaft from my 1931 RM Box (should be BP93) it is 19.5 ins.

David many thanks and interesting.  I presume you have a 3 sheen box, which axle do you have on your car?

Thanks

[DavidK]

Measured the propshaft from my 1931 RM Box (should be BP93) it is 19.5 ins.

David many thanks and interesting.  I presume you have a 3 sheen box, which axle do you have on your car?

Thanks

Yes, 3-speed gearbox and 4.9 banjo rear axle.
Looking at the Part's Lists BP73 has all the same fitments but slightly different profile at both ends.
BP73 appears rounder, in the picture, at the carden end. Being the same length is not surprising as gearbox and rear axle are almost identical. I also have a BP73 somewhere, i will get it out and compare more accurately.

[JonE]

Any chance of a photo of the two, David?

[JonE]

here are the BP73 and 93 together.. but they are only Austin drawings so care needed? 
There is also an image of the shorter prop here which links to the axle shown - is it a type 2 or a type 3? The longer one I'm not sure what it came off, but we can probably infer something once I know the exact axle type.
               

[JonE]

the images above... shorter one (type 3 axle presumed) and later 3 speed gearbox) 19.5" to pin
other is 20" to pin, so presumably standard early chummy.

But, following the thread lead, if that IS a type 3 axle then the shorter one should be a BP93.... but would make it same length which is obviously wrong! Please could we get more measurements for props that have been know to link to type 1 or type 2 axle with the later 3spd gearbox. I'm presuming that the arrangements for type 2 and 3 axles are the same, otherwise there would be yet another part number needed.