Lancia Motor Club

Model Technical and Interest => Augusta => Topic started by: rutley1 on 22 November, 2020, 04:23:07 PM



Title: Propshaft Installation - Augusta works cabriolet
Post by: rutley1 on 22 November, 2020, 04:23:07 PM
Can anyone please inform me if it is possible to get the bare propshaft installed with both the gearbox and back axle in place?  Having spent all day lying in the dirt, whether installed from the gearbox end or the axle end, the propshaft fouls the casings and will not slide into the tunnel.
Please don't tell me that I have to take the engine out again.  Am I missing something?
Regards to all
Richard


Title: Re: Propshaft Installation - Augusta works cabriolet
Post by: Mikenoangelo on 22 November, 2020, 09:36:22 PM
I can't speak for the cabriolet but for the normal saloon there is no difficulty in removing and refitting the propshaft. Undo the rear U/J first.  It comes out towards the back. It would be surprising if the semi- chassis version were designed without this capability since it would be a pain in the butt to service.

The only thing I can think of to make it difficult would be if the centralising spiders which have a socket to engage with the end of the gearbox output shaft and the pinion shaft at the back, have been wrongly assembled with the spiders between the disc and the gearbox or axle sides of the discs which would make the sockets engage more deeply with the two shafts thus effectively increasing the effective length of the prophaft. I would still hope that if you remove all the bolts you should be able to remove the shaft. The spiders should  be to the propshaft side of the discs as their function is to keep the shaft in axial alignment with the gearbox and axle. If assembled the other way they contribute nothing.

Morris Parry or James Parry would know about the cabriolet - they are rebuilding one. James has posted on here as Chugga Boom and his email is shown in his details.

Mike


Title: Re: Propshaft Installation - Augusta works cabriolet
Post by: Mikenoangelo on 23 November, 2020, 08:57:02 AM
A further thought - I think I misunderstood the problem - not connecting the propshaft to the gearbox and axle but just getting it into the tunnel? Is the car jacked up with stands under the back axle or propped up by the chassis? Jacking it by the axle would compress the springs a litte and push the axle up to give more clearance. I stood my car on 9 inch concrete blocks when working underneath.

Mike


Title: Re: Propshaft Installation - Augusta works cabriolet
Post by: rutley1 on 23 November, 2020, 01:06:32 PM
Mike, thanks for your ideas.
I am rebuilding the car after a long restoration.  The engine and gearbox are installed and running.  The rear axle is overhauled and fitted to the car.
The car is now up on axle stands and I am trying to slide a bare (no couplings fitted) prop shaft into the tunnel.  Whether I start installation at the gearbox end or the axle end, the prop shaft fouls the casings when 95% installed into the tunnel
As you may know, the gearbox cannot be pushed to one side and the rear axle casing removal would require dismantling the differential including half shafts etc.
Iíd be surprised if getting the propshaft into the tunnel involves major surgery.   Lancia design is normally so cleverly thought through.  I must be missing something?


Title: Re: Propshaft Installation - Augusta works cabriolet
Post by: rutley1 on 23 November, 2020, 01:24:49 PM
Everyone - after writing the last response I tried once more and finally slid the propshaft into the tunnel !  Itís a case of juggling and rotating the spider ends to avoid the casings.  Many thanks.
Richard


Title: Re: Propshaft Installation - Augusta works cabriolet
Post by: Mikenoangelo on 23 November, 2020, 07:55:51 PM
Well done!

Mike


Title: Re: Propshaft Installation - Augusta works cabriolet
Post by: rutley1 on 27 November, 2020, 09:45:07 AM
Epilogue

Lessons learnt!
1. Install the propshaft before the engine for an easy life.
2. With the engine and rear axle already in place, the only way to get the bare propshaft into the tunnel is from the rear and on the side of the rear axle with the oil filler. The differential casing close to the oil filler plug has a scallop that just allows the propshaft spider to clear.
3.  Check coupling disc thicknesses before trying to install.  A new coupling obtained from Cavalitto was much thicker than the originals (at the thickest point 19.75 versus 13.3mm of the originals).   This extra thickness made the new coupling almost impossible to install.  The axial position of the gearbox and rear axle are non adjustable so there is only a finite space available for the propshaft and couplings.  The extra thickness of the new coupling made for an almost impossible installation with much distortion of the coupling disc and resultant preload of the bearings.  I gave up and used original couplings from the car even though the condition wasnít great.
4.  Be sure that the couplings are installed with the centralizing spigot cup bolted to the propshaft spider (see photo) otherwise the whole assembly can whirl with resultant vibration.

Hope the above is useful to someone else.


Title: Re: Propshaft Installation - Augusta works cabriolet
Post by: Mikenoangelo on 27 November, 2020, 10:09:05 AM
I believe the correct thickness of the fabric in the coupling is 11mm which is what I found on the one aged coupling on  my car which is just the same as the old one in your picture. I have a new Italian coupling whch looks like your yellow version but the fabric is only 8mm. I am awaiting new couplings made in the UK, having concluded that the skinny one is responsible at least in part for vibrations.

Mike