Gearbox Coupling Plate

A question for the technical wizzes.

Those who have followed the saga will know that I recently had my
second-hand BMC 2.52 rebuilt by Peter Atkinson at Farncombe
Boathouse on the River Wey. Unfortunately he died two weeks ago.
Luckily for me he had rebuilt the engine and bench tested it before
that sad day, so things could have been far worse.

However, the gearbox, a Newage Coventry Ser No: 24-14565 is still off
the engine. I can't find a type plate on the box, but it is one of the
bigger ones about 25 years old [though hardly used, like the engine.]

There is a circular aluminium drive plate that bolts on to the engine
flywheel. It has three shaped lugs on it facing back towards the
gearbox. On the gearbox shaft is a similar circular plate made of
steel, also with shaped lugs projecting forward. It appears to be held
in place by a bolt tapped into the end of the splined shaft. The
'shapes' on the lugs don't match up, but the two halves face up
together, giving about a quarter of an inch play in rotation.

When Peter stripped the engine he told me that 'rubber biscuits'
should have been fitted between the lugs, but they were never there!
However, as the engine had only done about 30-40 hours running, no real
wear had taken place on the lugs.

Having inspected the drive coupling myself, I don't see how loose
rubber 'biscuits' could be located on assembly. After all, the coupling
is inside the bellhousing, so on assembly you couldn't get at it.

I am now wondering if these two plates, one on the engine, and one on
the gearbox shaft are in fact two halves of a coupling assembly that
has broken apart when Peter took the gearbox off. The only other
gearbox drive couplings I have seen were shock-absorbing assemblies
that replaced a clutch.

I suspect I will have to find a new coupling from somewhere.

Can anyone shed any light?

Much appreciated.

Tony H

.

Relevant Pages

  • Re: Gearbox Coupling Plate
    ... >> Luckily for me he had rebuilt the engine and bench tested it before ... It has three shaped lugs on it facing back towards the ... >> gearbox. ... >> Having inspected the drive coupling myself, ...
    (uk.rec.waterways)
  • Re: Gearbox Coupling Plate
    ... > Luckily for me he had rebuilt the engine and bench tested it before ... > However, the gearbox, a Newage Coventry Ser No: ... It has three shaped lugs on it facing back towards the ... > Having inspected the drive coupling myself, ...
    (uk.rec.waterways)
  • Re: BMC to Newage Coventry Coupling Plate?
    ... >I recently had my second-hand BMC 2.52 narrowboat engine rebuilt by ... >However, the marine gearbox, a Newage Coventry Ser No: ... It has three shaped lugs on it facing back towards the ... >Having inspected the drive coupling myself, ...
    (uk.rec.engines.stationary)
  • BMC to Newage Coventry Coupling Plate?
    ... I recently had my second-hand BMC 2.52 narrowboat engine rebuilt by ... However, the marine gearbox, a Newage Coventry Ser No: ... It has three shaped lugs on it facing back towards the ... Having inspected the drive coupling myself, ...
    (uk.rec.engines.stationary)
  • Re: Automatic -v- manual gearboxes; whats in a word? (Was Re: Question for any engineers on
    ... ECUs and even a gear stick and linkage is ancillary, ... Only a fixed ratio gearbox fulfils that definition. ... within itself, according to engine load and road speed and, regardless of ... gear using dog clutch synchronisation prevalent in manual gearboxes. ...
    (uk.transport)