PDA

View Full Version : Clutch not disengaging



ybt502r
12-22-2013, 10:41 PM
I've been reading past posts, and I would like to check the bigger brain here before I start disassembling. My LHD late Series III clutch really doesn't disengage - or "engages 1/16" off the floor" if one wants to look at the positive. I've had this vehicle for a dozen years but never had to touch the clutch. The fluid level was low, so I topped it and drove it about as well as I could. Very slight improvement but it still catches immediately off the floor.

I will bleed it in the morning, and I guess my next step is to try to adjust the master cylinder push rod (seems reasonably self-explanatory). However, to undertake the latter (I'm assuming bleeding won't fix it), I guess this means I need to take the wing off, then the 6 bolt cover to access the bracket? It is to loosen the lock nuts and adjust the engagement point?

This is the week of Christmas and there is over a foot of snow here. Impeccable timing. All suggestions / experience welcomed. This has happened to someone before.

morgant
12-23-2013, 05:34 AM
Yeah, definitely start with bleeding. In fact, if you've never had to do anything with the clutch in that long, I'd suggest draining & replacing the brake fluid in the clutch hydraulic system, then bleeding, as the fluid could have absorbed too much moisture or other contaminants over the years and so has lost the properties required for proper hydraulic operation. Remember to only use DOT 4 blake fluid, like the Girling fluid our hosts carry (http://www.roversnorth.com/ProductDesc.aspx?code=GBF4500).

From there, adjusting the clutch pedal height is helpful, if it's out of spec. The lower edge of the pedal should be 5.5 inches from the floor, there should be a minimum of 6mm free play in the pedal before pressure is felt, and there should be about 1.5mm free play between the master cylinder push rod and piston (all taken from the Green Bible). You are correct that, on the LHD model, you'll need to remove the wing (not difficult, as long as the fittings aren't badly rusted).

Hope that helps.

bugeye88
12-23-2013, 11:27 AM
As Morgant said, bleeding is the first step. Sounds like the fluid level dropped to the point that air was drawn into the Master and the fluid lost its ability to push on the slave cylinder very effectively. The question of where the fluid went should be looked at to see if the master and/or the slave need to be replaced or rebuilt. and the fluid that's left in the system is probably contaminated and needs to be replaced in any case.

Cheers,
Rob

Contractor
12-23-2013, 06:40 PM
In addition to the above advice, check and make sure your flex hose is not bulging.

ybt502r
12-23-2013, 10:57 PM
Thanks for the comments/suggestions everyone.

So the update to the day's work - I flushed the clutch fluid three times trying to get it clean. After all these years, it was pretty black. Took a bit of trial and error to get the bleed sequence down, but I think I (almost) got it. That pretty much was it, at least the first part. It now drives more or less like it always has, which is to say the clutch catches pretty close off the floor (just not the 1/16" that it was doing).

But now, having paid far more attention to this issue than I have before, I wonder if it is not properly adjusted. I did not take the left wing off to check the master cylinder push rod as I ran out of time. A question to the reading community - about where does your clutch catch when you lift the pedal from the floor? I get about an inch at best right now, and I think it's fully engaged by the time the clutch is halfway up. What's normal?