Thread: Please check my clutch fault finding diagnosis

Hello All,

Some time ago I went to do a job in the paddock with Snowy, my 110 Defender single cab ute with 200tdi diesel. When depressed about halfway through its travel I heard a squelch sort of sound and then the clutch pedal went all the way down to the floor. I checked the clutch master cylinder reservoir and it was low. I connected my Motive pressure bleeder and pumped it up. By using the pressure bleeder it tops the reservoir up with fluid as part of its operation. With the system pumped up I could not see any leaks at the master cylinder, flexible pipe or the clutch slave cylinder. Today I took this test one step further and I just went under Snowy and took out the bleed screw with the pressure bleeder pumped up. At the start there was a lot of air coming out and then it went to a nice solid stream of brake fluid. I left the nice solid flow going for quite a while. After tightening the bleed screw up, I disconnected the pressure bleeder and with the reservoir being full - I replaced the master cylinder cap. When I depressed the clutch pedal it again went straight to the floor - with the clutch not being engaged.

Diagnostic conclusion: I figure that if seals had blown in either the clutch master cylinder or the slave cylinder, or cracks in the flexible pipe or leaks at joints, then there would be brake fluid spewing out everywhere and there are no leaks. So therefore the hydraulic system is okay and the clutch hydraulics as a possible fault can be eliminated from the diagnostics. Is this a correct assumption?

Diagnostic avenues to be explored:
1) Frozen Clutch Plate due to inactivity the clutch plate might have frozen to flywheel. Possible solution - jack the rear wheels up and put in some axle stands. Make sure four wheel drive is not engaged. Chock the front wheels. Start the motor and bump the gear stick and see if the shock of the engagement of the gears breaks the clutch plate loose. Of course Snowy is parked out in the yard and is sitting on loose sandy ground. So to be safe Snowy needs to be towed into the shed to have the jack and axle stands located on the nice and stable concrete floor! No - I have not constructed my planned winch system yet. I did buy the winch and the steel universal beams. Just need to hire a bobcat with a large auger and arrange a visit by the mini-mix cement truck and to wait a week or so for the anchor points to cure. As yet, the availability of both spare time and disposable income have not aligned themselves. So, in the meantime, I will have to resort to the old fashioned tow with my tractor.

2) broken throw-out bearing clutch fork or yoke. As far as I am aware the only way to determine this is to separate the gear box and bellhousing from the engine ... sigh. If this is the case I might as well buy a full clutch kit because I do not know how old the clutch system is from when the previous owner may have originally fitted it.

Are these two possible options the only things going wrong that might result in the clutch pedal going to the floor with zero resistance when the hydraulic system seems to be fully functional? What other possible options of the clutch not engaging could there be?

What are the other possible causes and how can they be tested - without having to start separating the drive train. Sigh!

Oh and if it comes to my having to separate the drive train - what preventative tasks or maintenance should I be doing to the gearbox/clutch/rear of motor while I have good access to the area? For example, should I use the opportunity to replace the engine's rear main seal? Is this a problem with the 200 TDIs? I know the rear main seal was a problem with the Series Land Rovers.

Kind regards
Lionel

Originally Posted by Tins

Mike's always worth a look for Defender stuff.

Hello Tins,

Yes, I have been a subscriber to Mike's channel for a couple of years now. He has also been very kind in responding to my emails as recently as tonight. I must admit that I found the YouTube clip after Mike replied to my questions about the Heavy Duty Clutch Fork. I did describe the pedal movement and the no leaks in the hydraulics. Then after Mike replied I found that "what could it be" video. Well it is nearly midnight so that is me for the day. It is a workday for me tomorrow.

Kind regards
Lionel