Thread: No clutch after engine swap

Vid (hopefully) of the clutch fork:

The clutch is a HUGE PITA to bleed. I changed my MC a couple of weeks ago, and still haven't gotten all the air out. (it will eventually self-bleed).

However it should be easy to tell the difference between air and other issues. If it is air the brake pedal should be spongy, and if you disconnect the return spring the pedal should probably move halfway down under its own weight.

Brian (Bearman) gave me a hand after my MC failed south of Mackay, on the way back up north. Bleeding is a huge PITA as isuzurover said. It seems to form some sort of an airlock halfway up the tube, and is definitely a two man job. Interestingly, almost no pedal 'feel' until the airlock is reduced. A pressure feed, backwards, from the slave cylinder up into the reservoir would be very messy, but may solve the issue. Don't let the fluid get low, and good luck.

I got over the bleeding issue by slipping a 4" long piece of rubber radiator hose over the reservoir top and filling it up to the top of the hose, then bleeding it out. Worked fine

JC

Hopefully someone more experienced can confirm my thoughts.
Assuming its bled properly and you've got good pedal at the top of the stroke, there's only two things that could prevent the clutch disengaging:
1. Insufficient travel
2. Interference between the input shaft or friction plate and the rotating parts (pressure plate, flywheel, spigot bush).

Some theorising on insufficient travel ...
- If the friction plate or pressure plate was a bit on the thick side, could it result in "low" fingers on the pressure plate and not enough travel to disengage it (possibly the clutch fork input end hitting on the bell housing limiting travel).
- If the clutch fork pivot was worn significantly into the bell housing could it cause a similar thing
- Clutch fork not sitting in the detents on the release bearing properly
If it was something internal in the bellhousing I'd expect the clutch pedal wouldn't go down fully. Is there any difference in pedal travel when you have the bleed nipple open compared to when its closed? If it was slightly less with the nipple closed it might point in this direction.
- Clutch pedal hitting on something (rubber mat etc)

And some ideas on possible interference:
- between the gearbox input shaft and spigot bearing/housing. I'm guessing it would only take a fraction of a mm interference axially to effectively lock the input shaft and spigot bearing/housing together so that the input shaft always turns with the engine
- between the friction plate and the pressure plate housing
An option to check for spigot to input shaft interference would be to loosen the bellhousing bolts a couple of turns, and put some bits of sheetmetal/shim etc about 2mm thick between the bellhousing and adapter housing next to the bolts, then just tighten the bolts firmly (dont torque them up) and see if it allows the clutch to disengage.

Hope you get it sorted out soon...

Steve

I've also tried JC's method. Got a two inch off-cut of clear plastic tube on top of the MC reservoir. Ran a hose from the SC bleed nipple back into the top of the reservoir & kept re-circulating the fluid. If I can't bleed it in the next two days I'll go to Aldi this Sat to get this for $100:




Water resistant camera unit and tube
Great for viewing hard to see areas
2.4" LCD colour display
TV-out connector
SD card slots for SD cards up to 16GB

Will drill & tap an inspection hole in the bottom of the bellhousing o see what's going on.

Rob, do you remember which way the cluth plate went in, recess to the front or rear. Sounds to me like the hydraulics are working ok but it's still not disengaging.

Clutch plate can't be mixed up really as the centre hits the spigot bush & won't sit flush with the flywheel.