Thread: Series 2 to Series 3 gearbox change

The old LR manual is discussing the "3 finger" clutch, where there are 9 coil springs between the cover and the pressure plate. The springs on the diesel version are heavier than those on the petrol version, and the springs from the Rover 105 are heavier again. Each increases the clamping pressure on the driven plate, but also increases the pedal force required.

The later clutch cover clamps the driven plate in the same way, but uses a flat spring (diaphragm). My "book" is too early to discuss that version, but the same rules may well apply, i.e. different spring rates were available depending on the application?

In the earlier "3 finger" version it would seem that the springs are interchangeable (including the "105" springs) and could be identified by their colour.

Given that aftermarket parts do not always abide by colour coding, do not always relfect the full original specification (why make/stock/sell two different types when one will "more or less" do both jobs?!), and often parts are interchanged without full regard to original specs (for example my petrol SWB has a diesel leaf spring on the front driver side) it is entirely possible that two apparently similar components have different operating parameters. So a change in spring rate on the two clutch covers (3 finger or diaphragm) could result in the change in pedal effort without looking any different.

Originally Posted by peterg1001

Thanks John, I'll try a power booster on the clutch circuit. I can get a PBR VH44 for about $300, and that can be my next little project.

Stand by for photos . . .

Peter

OK, photos attached.

It turned out to be a very easy install, just draining the clutch fluid, bolting the booster in place, and making a couple of lines.

The difference it has made is profound - the clutch effort is now equivalent to a small saloon. Thanks John, a really good outcome.

The only downside is that the clutch now engages about an inch or two off the floor, instead of halfway (4" ??) through the clutch travel.

Is there an easy way to adjust the engagement point up an inch or two?

Thanks, Peter.

Thanks for the pictures.

Unless it is a very early slave cylinder setup, there is no adjustment at the slave cylinder (see manual). There should be no perceptible lost motion in the VH44, and assuming it is a change that was introduced with the booster, I suspect that the hydraulic system is not completely bled. The line from the m/c to booster looks as if it would be a likely place for air to be hard to displace from. One solution would be to cut the pipe at the highest point and insert a tee with a bleeder on it, although this may not be necessary - it may just need more bleeding. Remember it is possible to bleed at any junction by loosening the nut.

I assume that the m/c pushrod is correctly adjusted?

John

Originally Posted by JDNSW

Thanks for the pictures.

Unless it is a very early slave cylinder setup, there is no adjustment at the slave cylinder (see manual). There should be no perceptible lost motion in the VH44, and assuming it is a change that was introduced with the booster, I suspect that the hydraulic system is not completely bled. The line from the m/c to booster looks as if it would be a likely place for air to be hard to displace from. One solution would be to cut the pipe at the highest point and insert a tee with a bleeder on it, although this may not be necessary - it may just need more bleeding. Remember it is possible to bleed at any junction by loosening the nut.

I assume that the m/c pushrod is correctly adjusted?

Yes, the pushrod was fine before I started. I'll check the bleeding again, but it was looking pretty good by the time I finished, no bubbles at all in the tube to the waste reservoir.

Peter

Originally Posted by peterg1001

Yes, the pushrod was fine before I started. I'll check the bleeding again, but it was looking pretty good by the time I finished, no bubbles at all in the tube to the waste reservoir.

Peter

That does not necessarily mean there is no air in that upward loop. If the volume displaced by a pedal stroke is not enough to shift everything in the pipe to the bleeder, the air is likely to move back up to the highest point before the next stroke, and you never get it out. I can't think of another explanation for the lost movement.

John

Originally Posted by JDNSW

That does not necessarily mean there is no air in that upward loop. If the volume displaced by a pedal stroke is not enough to shift everything in the pipe to the bleeder, the air is likely to move back up to the highest point before the next stroke, and you never get it out. I can't think of another explanation for the lost movement.

There's a bleed point at the exit end of the booster cylinder (you can see it in the photo), I'll try bleeding from that point next weekend and let you know how I go.

Peter

Originally Posted by pop058

yes please

PAUL!!!!!! There is nothing wrong with your left knee......so don't even consider changing any of ya massive amounts of landies