Leak - any ideas?

[Gelandestrasse]

Thought I'd open the thread again as I took the gearbox off last night after a few evenings of dismantling/journey into the unknown.

On the way I found a sound bevel drive, splines, pivot bearings 'iffy', leaky rear shock (thanks Denzo), good swingarm and bearings, good shaft, some incredibly rusty fasteners that undid splendidly with perfect threads, one or 2 stubborn ones (particularly the top left subframe fixing).

When it came to taking the exhaust hanger bracket off the gearbox I found one fastener loose, the one closest to the leak.

It was a bit stubborn, but the gearbox came off and I discovered that it was all bone dry at the input/output seals and the balance shaft seal was also bone dry. Splines were a bit rusty hence stubbornness.

So I can only assume that the loose fastener (only one found) was responsible for the leak. I'm now going to decide whether to split the case and put some fresh sealant on the joint (along with un-needed new seals (input/output/clutch) or just to tighten the bolt when assembling and hope it doesn't leak. Any experienced views on that are welcome!

I've got some shots if anyone is interested, but just image what a 13-year old corroded gearbox looks like and you'll not be far off.

I'm also going to read up on clutch replacement while I am there. In the least I need to inspect and measure thickness of the friction plate.

 

[RallyeGS]

Whats the issue with the rear shock? Has it been refurbed?

 

[Gelandestrasse]

Whats the issue with the rear shock? Has it been refurbed?

Just leaky. Denzo did a refurb for me, massively quick turnaround. All tickety-boo.

 

[RallyeGS]

Yea, he's good at what he does, and quick with it.

 

[Gelandestrasse]

Update. Clutch measured up with plenty of wear to go, so after splitting the gearbox and cleaning the joint face I applied the thinnest bead of RTV and with a new input seal, fastened it all back together. A few new bolts here and there, a powder-coated subframe, all the stuff went back on without much drama - the driveshaft pivots were fine but a new sealing washer is on its way. I had an ABS warning light (front sensor) beforehand and discovered a worn section of the loom on the rebuild - a splice cured that and all working again. To get the bike started I had to empty out the fuel and also the injector fuel lines, plenty of water in there - the bike had stood outside for a few months before I got it.

Last night I took her for a run - it was great to be back in the seat of a TC! Fuelling was not right and finally she conked out - the second-hand feel pump controller had given up the ghost. So a new one on order (Motorworks honoured their secondhand parts guarantee and knocked the price of it off the new one), and a bypass made out of the old one. Bike is running happily on the bypass one but a few longer shakedown runs needed before gaining 'full' confidence!

And the gearbox is not leaking (at the moment)! A happy bunny.

 

[Headtester]

Well that all sounds like good news to me, excellent stuff.

 

[Gelandestrasse]

So I took the bike for a local ride last night (within pushing distance from home so I could give the AA a night off). I'm expecting the new fuel pump controller (FPC) today, so I used the old one with the output cables soldered directly on the input pins on the circuit board of the FPC to get the bike shaken down for all the other systems (satis). The bike ran perfectly well and fine; better than the other night (less/absent popping on the overrun).

But it's puzzling me. When you connect the fuel pump directly to 12V it runs continuously. But when I turn my ignition on, I was expecting the pump to run continuously - but it runs for a couple of seconds and switches off (like in the normal case). I've got the pump connected straight to the ignition-switched power. Any ideas why this is the case?

Bottom line is my by-pass FPC works; bike runs fine, I'll keep that with the bike. I'm expecting the new FPC to work too, so no problem.

 

[Mistacat]

When the ignition is switched on the pump runs for a couple of seconds and often does not get to full pressure, just enough to prime the system.
When the starter button is pressed the fuel pump starts to run.
There is not an electronic feedback circuit in the system .
The pressure regulator is mechanical and set at 60 psi on the TC and 45 psi on the pre 2010 bikes.

 

[Gelandestrasse]

When the ignition is switched on the pump runs for a couple of seconds and often does not get to full pressure, just enough to prime the system.
When the starter button is pressed the fuel pump starts to run.
There is not an electronic feedback circuit in the system .
The pressure regulator is mechanical and set at 60 psi on the TC and 45 psi on the pre 2010 bikes.

I know this stuff, but thanks. I have the pump hard-wired to ign-switched 12V so I was expecting it to run continuously when the ign was switched on. It doesn’t. It acts normally, as if the FPC is doing its thing. Baffled me a little. New FPC fitted now.