Classic engine, gearbox and drive questions

[rockingh]

Hi all. We are restoring a 30 foot wooden fishing boat built in 1900 and we are a charity. We are at the painting stage and are now getting to engine and electrics.
It was fitted with this Thornycroft LT120 120HP (Ford based), Gearbox Borgwarner 2:1.5 (we think) and would like some info from your members collected knowledge.
We have had the engine running and you can see lots of detail on http://www.floatourboat.co.uk.
Picture links, https://drive.google.com/drive/folders/0B3dgQHQ3lL50aDFEU3JnbTgwVG8?usp=sharing
Looking at the first picture a we aren’t sure what these drain pipes marked A and B are for, they come out into a union and are a very thin tube going down in to drip tray. A comes out of the injector pump and B from the side of cylinder head.
Also in the side of the engine is a wooden plug C which goes into a hole with a dog in the bottom. If it was a petrol engine I would have said a distributor but obviously not? We think maybe mechanical rev counter?

 

[burgundyben]

You could ask Mike Bellamy at Lancing Marine, he knows old Fords very well, its either a Dorset or Dover block.

Gearbox is a Borg Warner, 71C or 72C, the C is for co-axial, it is a reduction box, most likely 2:1 or 3:1. you can't check unless engine is running, when it easy to do with an optical tacho, checking both crank on front of engine and output flange on gearbox and comparing the speeds. You can put the box in a lathe, input splined shaft in the chuck, that way you can test it too.

Very simple box, all spares readily available from ASAP Supplies, it is possible to DOY rebuild if you've got someone good with spanners. Do not use synthetic ATF. Use mineral Dextron II.

 

[Paddy Layback]

An unusual boat and a very worthwhile project!

I never knew there were any double-ended smacks. It so happens that I sail about on a 60-yr old double-ender, though she was built as a yacht.

The very best of British to you, I look forward to seeing the Baden Powell in the flesh.

 

[bristoljim]

The B pipe is the leak off from the injectors,needs a small return line to the fuel tank.The A pipe is overflow from the fuel pump cam chamber.Don't forget to oil the governor on the fuel pump - hex plug on the top just behind throttle lever.

Jim