Had the recent experience of having no brakes while away from home base, fortunately Tim Barrington was graceful enough to help me out.

The nut that holds the pulley on the Plessey pump fell off and I had no brake pressure. A quick trip to an auto parts store resulted in nuts that did not fit (UNC and UNF) So it looked like it was BNF which is impossible to get.

Tim had the brilliant suggestion to pilfer a nut from somewhere on the gearbox, turned out that one of the gearbox mount nuts was just the right size, so I cleaned up the quill shaft and pulley bore, packed some grease into the bearing, fitted the pulley with a lock washer and the pilfered nut, tightened it as much as I could and put it all back together.

It worked perfectly.

Thank god for helpful people.

Having said that, I am now in search of the proper nut which I believe has a grease nipple as well as a tab washer.

Thanks

My bus number (if any): RM2133 (Albert Square)

The grease nipple is part of the quill drive shaft, not part of the nut. Are you sure the quill drive isn't broken? I have the right size nuts in stock if that's any help.

Your accumulators should have taken over if the pump fails, but you'd quickly lose gears as the compressor loses drive too.

My bus number (if any): RML2532

Thanks for the response. The shaft does not seem broken although the grease nipple may be- I'm not sure what it is supposed to look like and if someone has a picture they can email that would help.

The bearing seemed fine and there was still plenty of grease- I packed in some fresh grease just to be safe.

I'm not sure exactly when the pulley started spinning without turning the shaft but a new nut fixed it and it worked well all the way back even down some very steep hills

I had just charged the accumulators so it was braking ok until the flag dropped and the light came on.

Anyway, yes I would like to buy a new nut and a grease nipple if you have it please email me for details and if I can pay with PayPal

Thanks

My bus number (if any): RM2133 (Albert Square)

This all sounds very much like an emergency get you home measure. The pulley should require the use of a puller to remove it. If it has been spinning on the shaft then more than likely the interference fit has been destroyed so it is now only the tightness of the nut which is keeping the two in contact. I suggest you speak to the RM assoc. for an overhauled quill drive assembly and return yours for attention.

That was also in my thoughts! There's a deeper-seated problem there.

My bus number (if any): RML2532

The nut holding the pulley liberated itself at some point and indeed this was a "get it home" fix.

As the quill shaft is tapered I would conclude that "interference" would be relative to nut torque ( I also used loctite).

Notwithstanding, I will be replacing the shaft and nut and am having the bore of the pulley machined to clean up.

When checked, no excessive axial or radial play seemed present, however my intention is to replace the bearings and seal at the same time.

Would anyone be so kind as to provide part numbers for the bearings and lip seal?

Thanks for all the help

My bus number (if any): RM2133

Sorry I can't help with part numbers. I usually buy a complete overhauled unit from Imperial Engineering.

My bus number (if any): RML2532

The part number will be on the bearing and on the seal. If they aren't legible take the old units in to the bearing supplier.

I thought so, I would rather just have parts prior to starting.

Thanks for the help

My bus number (if any): RM2133

It won't be much use giving you part numbers since the quill drive was beefed up about 5 years ago with a different shaft which means your bearings may well be a different size.

That's good to know. Thanks

My bus number (if any): RM2133

Hence my comment about getting a replacement unit from Imperial.

My bus number (if any): RML2532