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Re: Carden Shafts

Hopefully they will have a mechanic old enough to have worked on Willème or the later PRP heavy vehicles, in which case the axle will possibly be familiar. The seal part numbers are, as said, in standard notation for seal identification, merely in the correct imperial units. It is easy enough to measure the relevant parts requiring to be sealed to arrive at these numbers. The n/s/r is the more difficult, but from underneath it is possible to see if the inner hub seal is leaking, so requiring a complete strip down. IIRC the Trident uses a ZF rear axle and it is a Trident rear hub bearing cup I use as a mandrel to fit the outer hub seal. They need to be reminded that n/s wheelnuts are left hand thread as is the n/s/r hub nut.

If they do need to remove the hub, then since it is a serious safety concern,'due diligence' requires a very careful inspection of the condition of the automatic brake adjuster operating link, and particularly its retaining split pin, once the peg bolt has been released in order to wind off the brake shoes. The details of the relevant part numbers, which are readily available from the UK,(Michael J Langley) are on the Forum. The link rods and brackets are replaced as an axle set.

Re: Carden Shafts

Going back to original topic, so the second-hand shafts are not worth using and therefore are you guys recommending that the RMOOA dump all their stock of second-hand shafts ?

Just asking ......

My bus number (if any): RM1368

Re: Carden Shafts

I don't think that's what's being said as some may well be very useable. Carefully check any that are being sold for re-use or get them overhauled by one of the firms mentioned.

Some of the "used" units may have had a short service life, others my be suitable for scrap, some are worth rebuilding.

My bus number (if any): RML2532

Re: Carden Shafts

The answer probably requires a vote from members, which I suppose could be done via a tear off slip in the magazine. The conundrum is that in any group of vehicle owners there will always be a section who just want 'another' part at the cheapesrt possible price. That section has to be catered for by the relevant club. Conversely there will be another group of members who want what they need 'off the shelf' as a service exchange unit, they accept that they will have to pay the full commercial rate for the privilege, but that is the level of service they want.In the middle unfortunately are the time wasters - who want to know that the part is on the shelf, but if they can get it £10 cheaper elsewhere they will wait a fortnight or longer.

From the club's point of view it depends on whether the space occupied by second hand propshafts could be better used. Imperial will I'm sure be able to advise whether it is worth stocking new shafts or if it is worth examing the stock witha view to selecting the best for attention. They will also know the spread of prices between a shaft made from genuine GKN parts and one made from Chinese parts. IIRC a genuine GKN UJ kit is in the region of £100 depending on the discount offered. A cheap alternative is about £25.

What I can say is that in the last 20 years I have only come across two sliding joints on a bus that were badly worn enough to condemn the shaft, some have been close however. Tandem drive is the complete opposite situation. Live cups in a yoke really have to be checked with a new joint to assess whether it is realistic to attempt remedial action.

Re: Carden Shafts

From my limited knowledge of carden shafts from 320 shop at Chiswick, LT employed at least 3 standards for the yokes and U/Js.
Depending on the wear, the housing was bored out to the most appropriate standard. Whether these "oversized" joints are available now I don't know.

What always intrigued me was the face on the connecting piece was surface ground to be absolutely flat. Was that necessary given that 8 or so bolts pulled it together on the the mating coupling?

In our case we may need one or two for an RML, but how do I get one from the RMOA that will be of use? Even in the UK if you are not near the stock, how do we get a good one?
Do I get a load sent over to try and hope one will be FFU?

What it probably needs is as Roy suggested, the 2nd hand cardens are assessed by a competent fitter for further use. I would suggest Lionel but getting hold of him is difficult and he is miles away from the stock.

My bus number (if any): RTL 960, RM 1585 and several RTs

Re: Carden Shafts

Everything to do with a propshaft is about balance. There is a limit to how long a rotating shaft can be without some form of central support. That is why one needs to use the tailstock when machining bar in the lathe. Think about the effect of a front wheel/tyre that is out of balance. Chiswick machined the mating face of a flange to ensure firstly that it would be falt and therefore clamped evenly, but also to ensure it would be rotating in a true palne to its mating flange.

I used to have an Alfa 75, this had the transmission as a unit at the rear of the vehicle. The propshaft uses rubber couplings - 'Guibos' This was balanced as a complete assembly even the nuts bolts and washers had to be kept in the correct specific location.

I was asked today to investigate at the end of the rally season a rumble and vibration which occurs between two specific speeds. The speeds coincide with what I would assume to be the most common constant velocity the bus ran at between distant stops. I made a considerable improvement a couple of years ago to the vehicle by renewing the centre bearing. I suspect the true culprit will be the worm drive axle, however I shall start by removing the propshafts for thorough assesment. They will more than likely be either slightly bent or out of balance at certain rpm.

Re: Carden Shafts

An interesting aspect there roy, that prop shafts can be in balance but out of balance at certain speeds.

I've seen some horrors abroad, an RM in Germany with a UJ so badly worn I fail to see how it could be driven for any length of time; and with the same owner a Bristol Lodekka with rubber bushes on the bearing housing that were non-existent. Luckily I found some shock absorber bushes that could be ground down to fit.

The RM prop shaft was only fit for scrap.

As an aside people sometimes ask if I can make their RM go faster. with the Cummins yes it is possible, but I wont do them as there's no guarantee of the condition of the porp shafts or UJs. Or the brakes for that matter. I wouldn't want to be held responsible for that lot vibrating through the entire drive train. It's not so bad on our bus where I can keep an eye on things and I know what may be wrong with it. Any vibration on the drive train can cause failures elsewhere.

My bus number (if any): RML2532