Monday, January 2, 2012

Clutch, crank and sprag clutch covers

I was very pleased with the way the Trophy's cylinder head cover had responded to my tender ministrations with Hycote VHT silver and clear. So I thought I'd do the same thing with the other engine covers. On the right of the motor, these are the covers for the clutch and for the crank and ignition pickups. All were tatty, the clutch cover the worst of the bunch. The picture below shows what lies beneath the right-hand covers, together with a glimpse of a chamber on top that contains secondary gear drives for alternator and starter.


The clutch cover is a very large casting incorporating an oil condenser labyrinth for the engine breather. There were  a couple of deepish scratches on its lower edge. More significantly, corrosion had lifted quite a bit of the paint and was clearly creeping upwards. The cover has a cast-in Triumph logo - I couldn't resist the idea of polishing it up.


For all that the paint was failing, it was incredibly hard to remove.  It took a lot of scrubbing with 3M pads, scraping and soaking in paint stripper to make any head way with it at all. Patience got a decent result in the end. However, in hindsight, I should have had the cases blasted clean.


 After two washes with soapy water and clean water, a day in the airing cupboard to dry out, I settled down to some spraying with VHT in my (too) well ventilated garage. Here is what it looked like after four or five light coats of Hycote Very Hight Temperature silver:


Another few days to thoroughly dry, then careful sanding with wet and dry on a foam sanding block took the paint off of the logo and brought it up to a good shine. 


Then it was a case of more washing off and allowing plenty of drying time before applying the top coat of Hycote VHT clear lacquer. 



On the left, there is a simple cover over the end of the crank. Later models run their breather through this cover - the early motors have the same arrangement as the 900s, breathing through the condenser labyrinth in the clutch cover.





I was tempted to pick out the Triumph on this side too but decided against it. I'm not sure why really. I might yet do that and give it an extra coat of clear.






There is also a top cover over the secondary gears behind the cylinder block, including an oil condenser mesh. The secondary gears couple the alternator and starter with the clutch basket. The starter spins the engine over by driving the clutch gear. The alternator is driven by the clutch gear when the motor is running.






Sprag cover


The very first engines has a secondary oil trap under the top cover, with a short breather pipe linking the clutch cover with a condenser chamber filled with wire mesh and a second breather pipe linking the secondary gear cover with the airbox.


Work in progress

3 comments:

bostik said...

Looks lovely. I particularly like the 'bare' alloy Triumph on the clutch cover.

Is the old girl going to be back running by spring?

bostik said...

Where's the alternator and water-pump gone? You working on them?

LeT said...

I stripped and cleaned the alternator brushes and regulator area. Next post ...