johny

My prop has play in the sliding joint but just needed straightening and balancing however dont know how the price of that will compare with a new one now. The advantage of reusing the original is that you can use quality UJs whereas I would expect any replacement to use the 6 pounds a shot ones....

Unfortunately I think your alternator is a later addition so your wiring isnt standard however, yes, most likely to be something in the permanently live system which is basically horns and lights....

You could try pulling fuses one by one to narrow down the search....

Ahhh you owners who start fiddling with Triumphs perfect design😲

No youve got the standard set up there... How much space have you got at the back of the engine to bulkhead and heater?

Everyone thinks bigger is better I suppose🤔

Think the brackets angle forwards from the engine so pushing it back a bit....

This page is very good: Propshaft Problems : Canley Classics

I see theres a used supercharger kit going on ebay that would probably help😁

Ha yes probably that front oil seal and as you say good for anti corrosion but unfortunately as the diff only has a pint of oil it also makes it easy to run low😞

Jonah have you downloaded the workshop manual for the Herald and Spitfire at vitessesteve.co.uk as it has lots of this useful info?

Its alright Colin problem solved and we're onto the horns now - keep up😂

As Colin says if its a modified Herald prop some 3" must have been taken off it. On a Vitesse there might be some room for engine position movement by which side of the suspension turret the engine support rubbers are bolted and also which way round the mount brackets are attached to the block....

Yes I dont think thats the normal arrangement for your car and it could have been installed by a PO or possibly even Triumph themselves. It doesnt allow as much movement as the sliding joint type (but then not much is needed), isnt so prone to wear but may not be as robust (Ive only seen them on Herald models). It would be surprising if the propshaft was exactly the right length so it doesnt surprise me the straps arent perfectly straight plus on the central sliding bar theres been movement so its been doing its job... As the manual probably recommends I would make it a part of routine maintenance to inspect the straps closely👍

Here you go:

First make sure the fuse is a real good contact as the horns also draw quite a current and wont work without a good voltage. You can try the volt drop test again at the relay supply purple wire when pushing the horn button...

Might be separate wires going onto the fuse holder so there could be crusty connector for the flash supply?

So not the purple to brown connector? It could be the fuse assembly itself even though the same fuse probably supplies other things...

Do the same test while progressively working back up the supply until the volts dont drop and thats where your high resistance is👍

That either means theres a massive current draw and you would have a blown fuse or lots of smoke! Or theres high resistance upstream somewhere like at a fuse or connector....

I think the lights all working ok Dan except flash so brown/red to blue/white good and failure is purple to brown to blue/white....

If this isnt the case then maybe you have a high resistance in the flash supply (fuse - purple wire - brown wire) so 12v shows but as soon as you try to power all the main beam filaments it cant supply enough current. You could check this with a voltmeter on any blue/white wire to see what reading you get when flash is operated compared to just when on normal high beam....

If 12v supply onto loom blue/white wires makes all main beam and warning light work then shorting brown column switch wire to blue/white must also make them all work no?

This is getting difficult as 'swopping brown leads'? Theres only one brown coming from the column switch and this has to connect to purple of the wiring loom🤔 Looking at your photo of the rear of the column switch the blue/white terminal looks very close to the red/brown - theres no short here is there?

yes your switch has a link as in my second diagram so only one blue/white wire needed. Looks like the fault is in the switch itself as if the brown wire onto it is live then when the flash is operated that contact on the back of the switch in your photo closes and puts 12v onto the blue/white wire which as youve already proved does power the headlights.... You should be able to short the contact with something and see it work👍