Gearbox problem.

[Hinesy]

Whilst I wait for my parts to arrive to rebuild my carb I thought I'd take a look at another issue today which is with the clutch and gear selection.

I can get all foward gears (just) but they are stiff to engage. I can also get reverse but half the time it will crunch in (guessing due to no syncro).

I'd noticed the bite point on the clutch pedal was low to the floor (maybe a few inches give or take).

Started by checking the fluid level, which is fine, no loss of fluid. Checked both the master, slave and pipe work front to back, no signs of any leaks.

Next step was to bleed the clutch, I used a pressure bleeder for this. Got a very small amount of air out at the start and some horrible black fluid. I've bled it right through until I got fresh fluid so confident there's now no air, but issue still the same.

I've checked the operation of the the clutch arm and it does move but I wouldn't say its by an inch as I've read.

From the paperwork I've got it has had a clutch about 40k ago but it was in 2004 so could possibly be an issue.

That's as far as my knowledge takes me so a couple of questions,

1. Can the slave or master fail without showing an external leak?

2. Is there anything else I should be checking before having the gearbox removed?

3. Previous owner had the gearbox linkage all refurbished just before my ownership, could this have been setup wrong? It does look like it was all marked up before and put back in the same place. Also doesn't explain the clutch pedal problem.

Many thanks,

Mark.

[multisi]

Best to change master and slave cylinders.

[Oldiebut goodie]

As usual I will post the likely cause - these vans are 30+ years old and this will more than likely be original.People tend to not look further than the hydraulics - the mechanicals need examining also.



 

[Hinesy]

Hi that the mechanism that attaches the clutch pedal to the master cylinder? Looks very hard to see with the dash in.

My pedal feels OK, maybe has 5-10mm of slack in it before it starts to operate anything. This to much?

[Oldiebut goodie]

You will have to lie on your back with a bright light and possibly a mirror to examine it. It is a sod pf a job to do.
In my pic you can see that a previous owner had adjusted it to compensate for wear leaving it to me to have it fail totally.
You should be able to feel any wear by pulling the pedal up by hand then pushing down until contact is made. 
Personally I would not just adjust it if worn as you can end up like I did with no clutch at all leading to a hairy drive home.

[Hinesy]

Just been out and had a look, not the easiest of jobs to do but not to bad in the end.

Found if you get the master cylinder off and out the way, hold the clutch pedal down out the way with a bit of wood you can get on the lock nut with a 15mm ratchet spanner and crack it off. I'm pretty tall so knelt on the floor while laying on my side in the foot well. I'm also left handed which also helps.

Anyway, there is a slight amount of movement on the clevis pin maybe about 1mm. I've adjusted the rod to remove the free play and put it back together.

The bite point has now moved up off the floor to a point I'd consider normal (somewhere between 1/4 and 1/2 travel).

It will now go in gear easier than before and will go into reverse without crunching. However it is still stiff although not as much as before.

Had another poke around at the linkage and found the part at the bottom of the gear stick where the onion bush is had not been put back on its original marks, moved this and better still.

Think I'm going to properly adjust the full linkage before doing anything else and see how it goes.

Thanks for pointing me in the right direction. I always like to check everything rather than firing the parts cannon at it.

[Oldiebut goodie]

Well done for getting in there!
I wish mine had been that simple.

[Hinesy]

I'm not calling it fixed yet, its still not 100%. But certainly a lot better, so a good start.

I had another T25 back in 2020 and that shifted pretty well so am comparing it to that, although that was a 5 speed, the current one is 4 and has half the mileage.

I'm a HGV diagnostic electrician so am not a complete novice when it comes to mechanics, I do like to get stuck in and understand things.

Thanks again.

[Hinesy]

Had a day on this today with mixed results.

As mentioned previously I'd managed to remove the free play in the clutch pedal and get a good bite point, however gears were still stiff to select (engine running or not).

I had already ordered a 025 motorsport 711 shifter to replace the standard one and it was my intention to solve this issue first the fit this afterwards. However knowing I'd have to readjust the linkage again I decided to fit it.

So fitted the 711 shifter and got into adjusting the linkage. Managed to get it to the point where I could get it in all 4 forward gears and reverse with little effort with the engine off and with the engine on and clutch depressed and I thought I'd cracked it. Took it for a good drive round town and shifting was perfect............ until it wasn't.

Was around 5 miles into the journey, doing around 50mph in 4th and had to brake hard to a stop. When attempting to pull away again I couldn't get in any gear. After a bit of messing pumping the clutch pedal and wiggling the stick they came back again and I drove the few miles home. Shifting was OK but some of the stiffness had returned along with the reverse gear crunch.

With the engine off its hit and miss now, you can go though all the gears 6/7 times perfect then it will sort of jam up and after some wiggling will come back again.

I'm going to see what it's like in the morning when it's cooled down and see what it's like cold.

Does this sound like a linkage adjustment issue or a box issue?

Any idea's tips on this would be appreciated.

Thanks, Mark

[multisi]

Crunching into reverse sounds like a clutch or hydraulic cylinder problem, try a new slave first.

[jrt]

Just to answer your first question, yes the master cylinder can allow air in without leaking. Mine did.
David.

[Hinesy]

That's what I'm leaning towards at the moment. It's just how intermittant the fault is that's throwing me.

Think I may try a master and slave and see how it goes.

If that's a fail I'll have to give in and take it to a garage. Removing a box is beyond what I think I can manage on the drive (especially when it's sloping and gravel).

[Hinesy]

Same thing again today.

Went for a drive, absolutely faultless from cold. About 3/4 miles in pulled over in a lay by to check my coolant level (I've just worked on the cooling system), jumped back in and couldn't get it in gear again. Managed to get in first eventually and drove home OK, got back and couldn't get it in reverse to get on the drive, after a bit of fight managed to get it in and parked up.

With the engine off but every thing still hot it will go in all gears but not as smooth as when cold.

**E D I T with more info.***

After some more tinkering I think I can now rule out the linkage adjustment.

With the linkage disconnected and operating the box manually I have the same issue when things are warm.
1st and 2nd are fine 3rd's fine but not quite as slick and 4th takes some jiggling and a slight bit of force to get in. Once in 4th it takes a bit of the same jiggling and slight force to get it back out.

Now however, everything is cold again everything is perfect again.

Gearbox oil is OK, previous owner mentioned it had just been changed before i bought it a month ago but checked it anyway, was fresh oil in there nice and golden. Didn't see any use in removing the drain bung to check for filings as I imagine they'll have been cleaned away during the oil change.

[Aidan]

If not a clutch issue then it's a binding spigot bearing, which I am afraid is a gearbox out to swap a £8 part I am afraid

[Hinesy]

Thank you.

Just out of interest do you think the issue is related to temperature or is it just coincidence it happened at around the same time?

With that in mind I think I'll hand it over to my mechanic. If the box has to come off is there anything else to factor in/check whilst it's off?

Thanks,

Mark.