New Project begins, 1974 P6 3500 V8

Check out the hydaulics.
Re bleed and check the clutch arm is moving enough, it sounds like inadequate stroke on the throwout bearing.
 
I did bleed it when I put the engine back in, if I didn't get all the air out and it has caused an inadequate stroke on the throwout bearing then is this enough to not let me engage gear 'smoothly' & having to 'crunch' it in but once in gear I could use the clutch fine, no drag or slipping etc??

Sorry to ask so may repetitive questions but I'm 'clutching at straws' :)
 
In my 'umble opinion yes. The gearbox needs to disengage from the engine in order to select a gear, once the selection is made then you will still be able to have the engine running and not drive when the clutch is depressed, admittedly there will be a drag on the engine, but you may not notice it.
You have nothing to lose by bleeding again to be sure, even more so in mind that it all worked before.
 
In my 'umble too, I still think it's a bit of clutch drag.

I am going to look a bit daft if it turns out to be synchros o_O
 
Hi All, Just to add when I managed to get it into first gear I could not select 2nd gear or any other gear with the clutch pedal down, didn't want to try it. I may pop just the box back on & bleed the system through & see it I can engage gears, wont fit prop shaft or exhaust etc, should only take an hour, least I check to see if any difference, thanks for all your input though much appreciated :), will let you know how I get on!
 
Still points to clutch drag to me tbh.

If you have, for instance, something on those splines when you put it together, and the input shaft got itself bound into them, then pushing the clutch in would allow the sprung plate to come away from the friction plate, but it could still have the friction plate pushed up against the flywheel. This would only cause a small amount of drag, but it could be enough.

When you put it into gear, the synchromesh pushes against the gear and causes its own drag, equalising the speed so you can engage the gear. If the clutch drag is too much to allow it to do so, then you will not be able to push it in.

I'm not explaining it very well, I'll see if I can get some pics later.

Have a really close look at the splines on both the clutch plate and input shaft, just to ensure there's nothing catching between them to stop them moving freely.

Did you apply a smear of grease onto the spigot and the splines when you put it together?
 
DamianZ28 said:
Hi All, Just to add when I managed to get it into first gear I could not select 2nd gear or any other gear with the clutch pedal down, didn't want to try it. I may pop just the box back on & bleed the system through & see it I can engage gears, wont fit prop shaft or exhaust etc, should only take an hour, least I check to see if any difference, thanks for all your input though much appreciated :), will let you know how I get on!
Click to expand...
You may have put it back in already but if not I would try the clutch on the splines first just to make sure it slides in and out ok
 
Hi Guys, Rich that is a great explanation, thank you :) I didn't put any form of lube on the splines or spigot bush which wouldn't have helped!
If for some reason there was causing clutch drag then this would explain why the final say 10mm was so hard to get mated when I fitted the block back in if something whoever small was misaligned. Haven't put it back in yet Stu but the clutch plate does fit over the input shaft splines nice & snug with no resistance in movement so to speak. I think also I needed to bleed it fully too,
I have video on my phone which shows slight movement in the centre of the clutch plate when I fit an old input shat into it, it does twist slight but no rotational movement, how do I upload it to show ? cheers :)
 
DamianZ28 said:
Hi Guys, Rich that is a great explanation, thank you :) I didn't put any form of lube on the splines or spigot bush which wouldn't have helped!
If for some reason there was causing clutch drag then this would explain why the final say 10mm was so hard to get mated when I fitted the block back in if something whoever small was misaligned. Haven't put it back in yet Stu but the clutch plate does fit over the input shaft splines nice & snug with no resistance in movement so to speak. I think also I needed to bleed it fully too,
I have video on my phone which shows slight movement in the centre of the clutch plate when I fit an old input shat into it, it does twist slight but no rotational movement, how do I upload it to show ? cheers :)
Click to expand...
Have you tried it on the actual box splines or just your old input shaft, wasn't sure by what you said.
 
Did you center the clutch when you mounted it to the flywheel? I bought a special black plastic tool with splines off ebay to do that.
 
mrtask said:
Did you center the clutch when you mounted it to the flywheel? I bought a special black plastic tool with splines off ebay to do that.
Click to expand...
Think he used an old shaft to align.
I wondered if maybe if there was a bit of surface rust on the gearbox spline then maybe the plate had gone tight
 
The spigot bush is made of sintered bronze. Its like a sponge and needs to be filled with oil before it is put into the flywheel centre. Grease clags them up. A dry spigot bearing will cause the input shaft to drag making gear changing very difficult. There are two ways to oil the bush. For thin section ones stick it on the end of your thumb, fill it with oil then use your other thumb on top and press down. when you see the oil appearing on the dry outside its done. Other way is to heat a small quanity of oil up in a tin and drop the bush it. Take it out when its cooled down and its done. Keep the temp lowish or it'll be stinky...
 
@mikecoombs, what would be the consequence of NOT pre-lubing the spigot bush before installation? I ask because I had no idea it needed to be filled with oil, and therefore fitted mine dry. – rolls eyes –
 
Best case is nothing but that's very rare. Normally input shaft keeps spinning (drags) when you depress the clutch until the bearing wears enough to free it up....That process can lead to the bronze welding itself to the spigot which will require cleaning off before new bearing is fitted. obviously as the bearing opens up the shaft loses support which can damage the bearing and gear at the other end. The dragging is what makes gear changing difficult, it can also squeal. From what you have said above I'd say the spigot is tight in the bush. If the car presented to me I'd take the box back out and change the spigot bush for a new one. they aren't very expensive and you will be guaranteed to have nice clean surfaces.
 
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