14 replies to this topic

[MiniCity89]

Hi all. Looking for some of your experienced help here.

 

The father-in-law and I have been rebuilding our Mini City 1989, which was taken off the road for approx 10 years. The rebuild has gone well, although taken some time. We have done lots of body and mechanical work. But we are now stuck with a new issue.

 

We installed a new verto clutch during the rebuild as the old one was worn out and seized. We got the car into a running order. All seemed well, I was test driving up and down the private road, prepping for its MOT, all was driving fine, in 1st, 2nd and reverse gears, when all of a sudden, the clutch would not engage. I had just stopped to put in reverse and turn around when I no longer had drive in the reverse gear, or any gear.

 

We checked all clutch fluid levels and free play on the release bearing, all seemed ok. The slave cylinder rod was still moving when clutch pedal pressed.

 

We removed the clutch outer cover to assess inside the clutch area. We were able to turn the engine over by hand and the fly wheel was moving. We were able to see the wheels turning slightly too, indicating engagement. We put it all back together and she ran. I got down the road. Stopped, reversed and turned back. Put in 1st and no engagement again.

 

We suspected a hydraulics issue. As we had not replaced the master cylinder or slave, so we decided to do that today. All replaced, along with a new flex hose. After pressure bleeding, the clutch pedal was back on and working the slave cylinder, moving the push rod back and forth, but unfortunately, still no drive!

 

Our next step is to dismantle the clutch casing again and this time remove the new clutch for a thorough inspection. Before we go ahead and do this, I am interested to hear if anyone else has had this issue or know what might be causing such an issue.

 

So, to summarise, the new clutch was working, the car was driving. Now it will not engage to generate drive, although it did temporarily after just removing the clutch case, turning the engine, and replacing the case again. All now hydraulic parts, sill no drive.

 

Your wisdom and help would be appreciated.

 

Colin

[sonscar]

The plunger with the two big nuts on it is known to seize.Check it moves freely in and out.Steve..

[MiniCity89]

Thanks @sonscar it’s definitely moving freely and we also checked the ball on the end of the arm and there is no defects or corrosion etc. 🧐

[imack]

Is it definitely the clutch that's causing the loss of drive?
I'm presuming you have pot joint driveshafts. Are the pot joints properly engaged in the gearbox?
Are the shafts properly engaged in the pot joint?
Could also be that the pinion nut has come loose on the gearbox mainshaft.

[MiniCity89]

Thanks Imack. Just had someone else suggest about the pinion nut. Certainly given us food for thought to investigate.

Neither of us were 100% sure it’s the clutch causing the issue as it was working. Just so many things can go wrong, hard to pin point. Thanks for the suggestions.

[bpirie1000]

Put it in gear with the engine off and lift the front see if the diff is alright... spin one side and the other should move, whilst in gear...

[MiniCity89]

Update.

Speedo housing removed, pinion nut seems fine, extremely tight and lock washer in place.

While it’s on axle stands, the wheel ms are turning and it has drive when I manually turn the engine over.

I can put Speedo housing back on and clutch components to retest, but I fear like last time it will drive down the road and then lose drive again.

Any other suggestions from anyone what might cause no drive? Even though it was driving fine.

[alpder]

I had a badly slipping clutch shortly after a[n almost] complete rebuild. Feared the worst. Quickly determined that the main pivot pin through the clutch/brake pedals was rusted and seizing, preventing the pedal from fully returning. Had an interesting drive home, having to put my toes under the pedal to force engagement after each gearchange.

 

Easy fix (if you've got a ballet-dancer friend who doesn't mind contorting into a double-S shape to reach the part.) Tip: don't take the pin fully out, or you'll have yourself a pedal-box reassembly project.

 

I don't know what the effect would be (or if it's even possible) but... could it mistakenly have a brake master fitted in place of the clutch master? Others here will know more about that [im]possibility.

 

Something you can try testing in the shed: Make sure the clutch is engaged - maybe by briefly releasing a hydraulic union to allow any residual pressure out. Have someone under the bonnet make an accurate observation of the lever arm position. Depress and release the clutch - say - a dozen times and check the lever arm position after each return. Does the clutch gradually "pump up" so that the lever arm returns less and less far each time?

Edited by alpder, 07 June 2025 - 02:23 PM.

[nicklouse]

What you are describing does not sound like a clutch issue.

I think you are thinking about the clutch wrongly.

 

the clutch is always engaged unless you press the pedal.

 

so with that in mind, wheels off the ground and in gear you should be able to turn one wheel on way and the other will turn the other way. The engine is stopping the gears moving so the diff will operate causing the other wheel to turn the opposite direction. If the other wheel does not turn look at the driveshafts. Inner pot joints? Change fitted correctly and not reversed putting the balls on the edge of the cup?

 

sounds like a drive train issue.as for it to be the clutch it will have to be having something stopping it getting into it’s natural state. Ie engaged. Or your flywheel is loose.

[MiniCity89]

Thanks NickLouse but at this point I don’t think it’s the clutch.

The pin and spring are pin, just installed a new clutch master, slave and pipe too.

Our thinking is possibly a diff issue and pot joints but with half the car to bits at the moment I just don’t know.

Was hoping for some suggesting from the gurus before rebuilding all back up again.

NB: on axlestands, wheels turn opposite direction. When out in gear and turned forwards together they turn the engine over, good sign.

Seems to be more an issue once load is applied and after just a short drive. The clutch must generally be ok to get into gear and drive down the road.

[MiniCity89]

Sorry that reply was for alpder

[MiniCity89]

@nicklouse wheels do spin in opposite directions when
Jacked up.

Wondering if could be the joint not being in fully and when down on the ground under load, it moves out.

Drive train could be a number of issues no?!? Hard to pin point.

[sonscar]

Drive shafts not fully home most likely wheel end would be my guess.Steve..

[amsgw]

Did you find the culprit in the end?

[MiniCity89]

Hi Amsgw.
No, not yet. I have checked the main shaft pinion nut, all was fine, now put that back together.

So clutch and mainshaft removed from the equation, I am now investigating the drivers side driveshaft. I have removed the driveshaft from the pot joint and will be examining it.

Question, if the suspension cone has potentially gone on the drivers side, could that maybe affect the driveshafts staying home in the joints under load?

Something is causing this loss of drive. And worth noting that before I lost drive, the front drivers wheel starting rubbing the wheel arch when hard turning left.

Thanks

Edited by MiniCity89, 28 June 2025 - 07:28 AM.