Gear change harder when engine warm

[a_d_jackson]

My mk1 drives lovely and gear changes are smooth but on a long drive once the engine is warm, it’s gets harder to change gear. There’s no graunching or clonks.

Is this normal or is something wearing out?

Ta
Andrew

[floormanager]

I had it. Had to adjust the clutch throw out stop.

[Oneball]

When was the last time you changed the clutch fluid?

[a_d_jackson]

New clutch and brake master cylinders and fluid last summer. Although the issue was not resolved after the change.

[a_d_jackson]

Struck me as odd that it would be smooth when cold and only become harder to change gear when it was warm.

[floormanager]

Struck me as odd that it would be smooth when cold and only become harder to change gear when it was warm.

increase in clearance, diaphram loses a bit of pressure? I had the same, new clutch, wear after a year, adjusted the throwout, all fine.

[Oneball]

Struck me as odd that it would be smooth when cold and only become harder to change gear when it was warm.

Clutch is dragging (not disengaging completely) when hot. Try adjusting the stops as suggested.

[AndyPen]

Struck me as odd that it would be smooth when cold and only become harder to change gear when it was warm.

Clutch is dragging (not disengaging completely) when hot. Try adjusting the stops as suggested.

Had this on the 970 a good while back. The oil ways in the Primary gear had gummed up so it dragged. Luckily only very lightly. Something to keep in the back of your mind if adjustment doesn't work.

[BRI MK1]

sounds like idler gear not shimmed right

[Spider]

When you say it gets harder to change gear, is it that the shifter itself gets stiff / hard or that it feels like the synchromesh is slow / hard to engage and so needing more force than usual to get it in to gear ?

[Smithmaps]

I had similar problems. All new clutch bits.

Is it a big engine and does it run an oil cooler?

I had very stiff 4th to 3rd till I fitted a 13 row cooler, and the problem went away immediately.

Think the oil gets too hot for the box on larger engines. Hence why BMC fitted coolers on the S's.

Also check the oil spec. I always use 20w-50 mineral that the engine and box was designed for. Just be sure somebody hasn't put something modern and thin in it.
Also, make sure you have greased the gear change linkage on the back of the box. A sod to get to, but simple prevention.
Guy

[Exminiman]

I had similar problems. All new clutch bits.
I had very stiff 4th to 3rd till I fitted a 13 row cooler, and the problem went away immediately.

Think the oil gets too hot for the box on larger engines. Hence why BMC fitted coolers on the S's.

That an interesting idea, always thought that Mini did not generally need an oil cooler - but, not crossed my mind it could be for the gearbox instead....

[a_d_jackson]

Hi Spider

I would say the latter, like it needs a bit more effort.

[Spider]

Hi Spider

I would say the latter, like it needs a bit more effort.

OK, cheers.

Sounds like could be clutch maybe just needing some adjustment, or primary gear.

If there's a lack of certain oil additives or it's a friction modified type of oil, this too can be al issue.

[Smithmaps]

I had similar problems. All new clutch bits.
I had very stiff 4th to 3rd till I fitted a 13 row cooler, and the problem went away immediately.

Think the oil gets too hot for the box on larger engines. Hence why BMC fitted coolers on the S's.

That an interesting idea, always thought that Mini did not generally need an oil cooler - but, not crossed my mind it could be for the gearbox instead....

The reason I sussed it, was because the gear change was absolutely fine when cold. So the only real change with a hot car is oil viscosity.