Clutch issues - mixing and matching parts?

[Neil Davies]

Got the engine mounted on the floorpan of my 70/72 project last night and tried to adjust the clutch, but having major problems.

Story is this - the car was a 1970 1500 model, but the pan was beyond repair so I got a 1972 floorpan off eBay. For the US loungers, in the UK we didn't get IRS on any manual gearbox, beam front pans, so both pans are swingaxle. The original 1500 swingaxle gearbox is now in the 1972 swingaxle pan, and the original 1500 motor had a new 180mm clutch fitted to it before bolting it up to the 'box.

Problem - when adjusting the clutch cable up it pulled the pedal up past a normal driving position and right back towards the drivers feet, far too far back to use. Push the pedal down and it moves a long way (like to a normal position!) before it starts to disengage the clutch. We ran out of adjustment on the cable so ended up with 2 17mm nuts between the clutch release arm and the adjuster nut just to try to get it to work.

Have I made a mistake in using the 1972 cable (2281mm) with the 1970 gearbox? Should I be using the 1970-spec cable (2260mm) instead? That's the only thing that I can think of!

[benssp]

what's the chassis number neil? also if it's a RHD Irs/beam axle pan wouldn't it be from a semi auto?

[Neil Davies]

Hi Ben, it's a 112 *** *** number, so definately a '72 pan. Don't think I was quite clear on my first post - the pan is still swingaxle, as is the gearbox. I didn't want to confuse the US guys with their funny IRS late models! I'll edit my first post!

[Neil Davies]

Right, found out a little more - think I've been supplied with a late clutch too - found some pics on thesamba.com and it does look suspiciously like the wrong one. I didn't think the throwout bearing looked right so used the original one, and I don't know if the centring ring was on the pressure plate. Have to pull the motor again and have a look, and probably have to get another clutch...

[benssp]

Neil, what clutch is it? if it's a new 3 finger sachs unit, you'll need to take out the packing clips which keep the plate depressed, alternatively you could change the arm and fit a bearing adapter sleeve and keep the much nicer later setup

[Neil Davies]

Not sure exactly what clutch - Dad fitted it to the engine while I was working on the heater pipes under the dash! I think it's a Luk diaphragm one, but I'd have to ask Dad...

[benssp]

If you're using a late pressure plate with an early bearing, you probably will have a problem! check the pressure plate, early ones should have a centre pad

[Martin]

take a look at the back of the preshure plate, has it got a ring on the fingers? if so then your gearbox shouldnt have a guid tube over the input shaft. if your box has the guid tube, then pull off the ring on the preshure plate. all should be good in the world again


they do it like this to cater for both box's


Martin.

[Neil Davies]

check the pressure plate, early ones should have a centre pad

I thought so - I didn't think that you could get a 180mm clutch in the late style so I didn't even think to check it before Dad fitted it. That'll teach me!

take a look at the back of the preshure plate, has it got a ring on the fingers? if so then your gearbox shouldnt have a guid tube over the input shaft. if your box has the guid tube, then pull off the ring on the preshure plate. all should be good in the world again

Hi Martin, I know the box doesn't have the guide tube - I spotted that last night. Hopefully the pressure plate is the late one without the ring which will be whats causing the problem! Then it can be fixed easily and I can tick another bit off the list!

[Martin]

if the box doesnt have the guild tube then you need the pad on the clutch, otherwise when you press the clutch the bearing wobbles, ie the fingers dont get pressed evenly and thats BAD.

[Jim Ratto]

check the pressure plate, early ones should have a centre pad

I thought so - I didn't think that you could get a 180mm clutch in the late style so I didn't even think to check it before Dad fitted it. That'll teach me!

take a look at the back of the preshure plate, has it got a ring on the fingers? if so then your gearbox shouldnt have a guid tube over the input shaft. if your box has the guid tube, then pull off the ring on the preshure plate. all should be good in the world again

Hi Martin, I know the box doesn't have the guide tube - I spotted that last night. Hopefully the pressure plate is the late one without the ring which will be whats causing the problem! Then it can be fixed easily and I can tick another bit off the list!

if it is an early type pressure plate, that ring could have been removed at some point in its life... and yeah causing the problem.
I "think" the pedal travel backwards towards you should be limited by the little stop that bolts to pan, shouldn't it? Seems like I was always messing with that little stop in my car. I think the procedure is you set the free play on the brake pedal with that stop (not the threaded shaft off the pedal to m/c!) and you set clutch pedal to match position of brake pedal, then adjust cable play @ wing nut. It's probably just the wrong pressure plate. 

[Bruce]

Neil, here comes a curve ball:
Since your gearbox is a 1970, it does not have the guide tube.  But it does have the casting modified to accept the guide tube.  All you need to do is drill and tap 3 M7 holes around the input shaft, then you can attach the guide tube from a 71-72 gearbox.  Also, swop out the cross shaft for the one from a 71-72.  Then you use all the late parts, including the throw out bearing that doesn't fall off like the early one does.  Remove the ring from your pressure plate.