Gearbox problem.

[Aidan]

okay cold, binding warm as engine warms up and each gear change loads it perhaps, the spigot bearing only comes into play when you press the clutch allowing the input shaft to be static and unloaded whilst the engine is still turning, if the input shaft is turning then the mainshaft is rotating at engine speed and you'd only be able to select a gear by banging it into gear of choice without regard to damage to dog teeth of gear and synchroniser, when stationary that is very hard that's why 1st and reverse are hardest to engage when spigot bearing is binding, it's like not having a clutch

[Hinesy]

That makes sense and does fit with the symptoms. When I pulled over I couldn't get it in first at all but it did eventually 'bang' into gear. Also fits with not been able to get reverse which eventually ground its way in.

Does this fit with having the same issue with the engine off as well until it cools down? Although you can get the gears after turning the engine off its still stiff compared to when cold.

I've just been round the block in it from stone cold (only about half a mile) and it's spot on. I'm not using the van at the moment apart from short test drives after repairing so will carry on with this until sorted so I don't damage the box.

I'm assuming the clutch is disengaging OK as I can start it in gear without it lurching forward so sounds like the spigot bearings the favourite at the moment. I'll get it booked in and keep updating on here hopefully be a simple ish fix.

Sorry for all the questions, I work in the trade as a heavy goods auto electrician and like to understand things even if I'm not able to repair myself.

Thanks again.

Mark

[silverbullet]

This still sounds like a dragging clutch to me. The slave might be marginal when cold, then fails to hold pressure when warm (above No3 exhaust)
Renew both cylinders and pressure bleed it.

[Hinesy]

Hi, thanks for the help.

So if I'm understanding correctly the thinking is that the slave is OK when cold, then when hot is still working just enough to stop the engine stalling when the pedal is depressed but not enough to fully disengage the clutch to allow gear selection?

Since I can change the cylinders and bleed it up myself, plus the cost not been to bad, I think I might change them and see what happens before possibly paying the garage to do the same.

If it doesn't sort it at least I'll have piece of mind that they are OK for the future.

Thanks again.

[jrt]

Yes that sounds sensible, they’re both easy to change.
Access to one of the nuts on the slave can be a bit of a pain and I had to take the hard line off with the old slave and undo on the workbench as it was a bit tight.
The master was easier with a bit of stretching on my back on the cab floor .
Give everything a brush/ spray with plusgas first.
David.

[Hinesy]

Thanks for the advice.

I'll give the bolts a good spray up over the next few days they do look pretty crusty.

I've had the master off already so pretty confident with that now.

Parts are on order from Brickwerks and should be here tomorrow, fingers crossed will get an answer at the weekend.

Cheers

[Hinesy]

Yes that sounds sensible, they’re both easy to change.
Access to one of the nuts on the slave can be a bit of a pain and I had to take the hard line off with the old slave and undo on the workbench as it was a bit tight.
The master was easier with a bit of stretching on my back on the cab floor .
Give everything a brush/ spray with plusgas first.
David.

You were right about the pipe into the cylinder. Finished work early today and decided to get a head start on the slave. I'd soaked everything in plusgas yesterday and gave it another dose whilst I was getting the tools out. Could not budge the hose into the slave. Managed to get it undone at the other end, then it came off pretty easy. Got it in the vise and soaked it again, absolutely solid. Got fed up after 20 minutes of trying the usual tricks, decided just to go for it and it rounded off. Thank god for next day delivery. New pipe on the way.

[Hinesy]

Does anyone know how the lever that the slave operates should feel when it's disconnected? Should it be pretty loose of should there be some resistance?

I've noticed mine has a bigger range of movement operating it by hand than it did when the slave was connected, so that's a good sign. I was expecting it to be springy as the release bearing presses on the clutch plate but its kind of floppy, although the lever will stay in any position you put it and you can hear something tapping inside the box.

Thanks,

Mark.

[Aidan]

loose (may be tight depending on corrosion between case and nylon bush) before meeting resistance that you won't overcome by hand; in operation throw is around 10-15mm, from 10 o'clock to 9 o'clock sort of arc.

[Hinesy]

loose (may be tight depending on corrosion between case and nylon bush) before meeting resistance that you won't overcome by hand; in operation throw is around 10-15mm, from 10 o'clock to 9 o'clock sort of arc.

That's a relief thanks. It's not tight at all, as far as i can move it anyway.

At the moment I have the new slave fitted but no hydraulic pipe on yet until new one arrives. The arm is sat in between 9 and 10 o'clock.

[Hinesy]

Bit of progress tonight.

I'd already fitted the new clutch master and slave and had chance today to fit the new hose and bleed it up.

Pedal felt instantly better nice and firm and biting point good.

Went for a drive and all was good, until 5ish miles in (again) and it started stiffening up, although it has to be said nowhere near as bad as before. Couldnt get first at the lights but got second easily then managed to get first again. Before I couldnt get any gears when hot but seems to be just first /reverse now.

Think I've possibly had more than one issue and the cylinders have partially sorted it out as its alot better but not quite right.

I'm going to book it in to the garage now to pull the box and check out the spigot bearing, clutch etc and hopefully bottom the problem fully.

Thanks again for all the advice.

[Hinesy]

Another update on this issue.

Strangely, for now anyway, it seems to have fixed itself!!!

I'd took it for a road test on Friday after doing some work in other areas and only once I had a very slight issue selecting first. It went in first go but had to push harder than usual. The rest of the journey was fine.

With the above in mind and having fixed all the mechanical issues with the van I decided to go for a extended drive today (with my AA card firmly in my pocket). Did nearly 70miles and it was pretty much faultless. No issues at all with the shifting.

After checking the MOT history it seems the van has only covered 400ish miles since 2020 so wonder if everything was just a bit stiff??

Something to keep my eye on I think.

[silverbullet]

Happy days! We love a self repairing van here.

[Hinesy]

Happy days! We love a self repairing van here.

Wish I felt the same. I'll just be paranoid now waiting for it to break down.

I'm still going to have the box off, but I've just pushed it a bit further down the big list of jobs.