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Michael Moran
Experienced User
Username: mjcmoran

Post Number: 15
Registered: 8-2005
Posted on Sunday, 15 June, 2014 - 12:08 am:   Edit PostDelete PostView Post/Check IP

Hello guys once again from Warsaw (PL)

I am up to dealing with the more simple mechanical problems but this one defeats me. Quite a challenge running a Silver Shadow (SRH 18723) here in Poland. Have owned the car for 30 years and cannot be parted from it.

In attempting to trace a slight vibration(that dreaded word again!)on acceleration between 35 mph and 50 mph which then fades away, we (my Polish mechanic and I) have discovered that the coupling flange at the rear of the transmission casing seems to be slightly loose in the casing itself. The smooth gear changes seem to be entirely unaffected by this but perhaps this is contributing to the vibration.

Has anyone come across this particular problem ever before? No sign of external damage or impact.

An exchange gearbox is not a particularly pleasant financial option way out here!

The Workshop Manual does not really explore this part of the gearbox in any diagrammatic detail as to construction so I am not sure what is in there actually that might/could be replaced.

Best as ever

Mike

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Brian Vogel
Grand Master
Username: guyslp

Post Number: 863
Registered: 6-2009
Posted on Sunday, 15 June, 2014 - 12:42 am:   Edit PostDelete PostView Post/Check IP

Have you considered that it might be the Detroit/trunnion joints?

I've often heard the "vibration starting at speed X and fading out at speed Y" as being traceable to uneven wear on the trunnion joints.

The good news with that is if it is the actual cause, and these have never been swapped from side to side on the final drive, you can do that and effectively get new wear faces that should last you quite a while.

I know it's "one more thing to think about," but there it is.

Brian
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gordon le feuvre
Experienced User
Username: triumph

Post Number: 36
Registered: 7-2012
Posted on Sunday, 15 June, 2014 - 01:09 am:   Edit PostDelete PostView Post/Check IP

daimler aprts cat. for GM 400 (Part no RTC99887CD) shows bolt holding flange on,would not think that some one as small as Jag/daimler would have changed the box, just for them?
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Michael Moran
Experienced User
Username: mjcmoran

Post Number: 16
Registered: 8-2005
Posted on Sunday, 15 June, 2014 - 01:14 am:   Edit PostDelete PostView Post/Check IP

Thanks Brian.

I did know about this 'fix' for that type of vibration but have held off the swapping. I remember with horror reading the huge correspondence (100 posts) on this vibration issue from a chap in Belgium was it?. I never discovered if he actually solved the issue and how. Too often interesting threads are abandoned and one never learns the final outcome.

What is actually worrying me is the seating of the coupling flange at the rear of the transmission. I would have thought that if this was a serious matter it would have interfered with reverse gear or some other aspect of the transmission. At present there is no noise, leaks or anything else untoward from that area.

Mike
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Brian Vogel
Grand Master
Username: guyslp

Post Number: 864
Registered: 6-2009
Posted on Sunday, 15 June, 2014 - 01:39 am:   Edit PostDelete PostView Post/Check IP

Michael,

You're referring to Benoit Leus and the thread, Vibration Made Worse. The last post was May 13th of this year and it appears that this is still an ongoing issue, though some progress has been made.

My gut says that yours is correct, but this is not an issue I've had to deal with, so that doesn't really matter.

Best of luck in sorting this out.

Brian
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Michael Moran
Experienced User
Username: mjcmoran

Post Number: 17
Registered: 8-2005
Posted on Sunday, 15 June, 2014 - 02:43 am:   Edit PostDelete PostView Post/Check IP

Brian

Just out of interest, my mechanic has checked a number of other Shadows in his garage and they all have a slight movement in that coupling flange but without 'my' vibrations so perhaps this is not the cause at all.

You would be surprised how many Shadows are in Poland but mostly off the road - possibly 40! Perhaps one or at most two mechanics with any experience and knowledge of the model for obvious historical reasons. Translating technical terms from the Workshop Manual into Polish is a nightmare. I tried to set up an R-REC Section here but no takers.

I will probably do the Detroit swap eventually but as the vibration is not major, the climate here militates against extensive use of the car throughout the year and as I seldom drive long distances in it these days...mainly picnics and sightseeing with friends...I might postpone this task.

You might like to glance at a few postings on this link to see the car 'in action' as it were:

http://www.casualcars.blogspot.com

I use this forum because Australians are full of enthusiasm and information - me being Australian way out here also helps psychologically!
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Jeffrey McCarthy
Grand Master
Username: jefmac2003

Post Number: 431
Registered: 5-2007
Posted on Sunday, 15 June, 2014 - 07:18 am:   Edit PostDelete PostView Post/Check IP

My "vibration on acceleration between etc" problem only appeared after I had the gearbox completely removed, rebuilt and re-installed so perhaps the flange is the problem; is that easy to fix?

Also how major a job is swapping over the trunion joints for an experienced mechanic; roughly how many hours work if anyone knows. I've been putting off renewing the rear wheel bearings but perhaps it can all be done at the same time?
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David Gore
Moderator
Username: david_gore

Post Number: 1391
Registered: 4-2003
Posted on Sunday, 15 June, 2014 - 10:56 am:   Edit PostDelete PostView Post/Check IP

Michael, I overhauled the Turbo 400 on DRH14434 in the late 1990's and observed the same movement of the coupling flange; I spoke to a friend of mine in the USA who had some experience with the T400 and if my memory is correct he suggested this should not be a concern as movement of the drive shaft whilst the car was being driven would force the flange against a collar inside the transmission to take up the slack. The car is no longer in the family so I cannot indicate whether any subsequent problems have occurred.

Jeffrey,

Replacing the rear wheel bearings is not a job for the faint-hearted as the following threads on this forum indicate and there are excellent articles by Bill Coburn in Tee One Topics Issue 63 page 896 and Issue 94 page1270:

http://au.rrforums.net/forum/messages/17001/6864.html

http://au.rrforums.net/forum/messages/30/11377.html

http://au.rrforums.net/forum/messages/17001/14295.html

http://au.rrforums.net/forum/messages/17001/10010.html

http://au.rrforums.net/forum/messages/17001/1279.html

http://au.rrforums.net/forum/messages/17001/2466.html

Swapping over the rear drive shafts is a relatively straight forward operation with the exception of the necessity to avoid dropping the washers from the Detroit joints into the differential housing whilst removing/replacing the shafts. It is also good practice to replace the rubber boots at the same time and getting the replacement boots over the pin is difficult however the procedure required involves lots of hot water to soften the boot before installation and use of a good rubber lubricant. It is also very good practice to replace the rear discs at the same time if they show considerable wear. The outer universal joints should also be checked and replaced if necessary.
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Jeffrey McCarthy
Grand Master
Username: jefmac2003

Post Number: 432
Registered: 5-2007
Posted on Sunday, 15 June, 2014 - 12:31 pm:   Edit PostDelete PostView Post/Check IP

Thanks for that David. I've got some reading to do! I'll be getting Bob Chapman(and/or his son)to do all the work. I'm not young enough,well enough set up or experienced enough to try this sort of thing. I've also decided I'd like to actually drive the thing more and fiddle with it less;it's been a long 6 years of constant slog but she's almost completely restored/refurbished.
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Michael Moran
Experienced User
Username: mjcmoran

Post Number: 18
Registered: 8-2005
Posted on Sunday, 15 June, 2014 - 05:43 pm:   Edit PostDelete PostView Post/Check IP

Always such an excellent response on the Australian RR Forum!

This latest problem has caused me to reflect on my 30 year ownership of this marvellous and underestimated model, the 1975 Silver Shadow. The car is completely original and now almost 40 years old. I cannot think of any other marque of car that would still be running so well and looking so glamorous without any major repairs or bodywork. 76,000 miles on the clock.

Of course I have done all the 'extras' recommended - renewing all flexible brake and accumulator hoses, strengthening the rear cross member fixing to the boot floor a la Richard Treacey's wise preventative maintenance advice, resetting the rear springs when sagging was evident, checking the Pitman arm for cracks,only using the 'old' 'blue' non-organic coolant changed every two years and so on. The braking system has been my main bugbear over the years.

I know, I know, of course with the limited mechanical experience of these cars in Poland (for the best historical reasons) I should never have brought it here but a significant long distance and social touring history has accumulated with me now. So much pleasure in so many different guises over the years. The beautifully comfortable, only slightly worn interior always welcomes me as a close friend. We simply could not part when I left London. And so we became a happy 'menage a trois' - the Shadow, myself and my Polish wife.

Emotionally I find it terribly hard to sell cars and regret selling almost every classic I have ever owned (Bristol 400, Jaguar XK 150, concours MGB Tourer, Alfa 1750 GTC, MG TC, Jaguar V12 E-Type). Always sold for 'impossible' domestic, garaging, work or financial reasons - naturally not simultaneously but over the years. I am now 67 and had my first MG TD in Sydney when I turned 17. Also I regret those I have missed owning because of maintenance fears, of not being 'up to the job' (3.5 litre Thrupp and Maberly Derby Bentley, LHD 1996 Bentley Continental R, Maserati Ghibli, Lagonda Rapide).

If one is not an engineer or mechanic these days it almost precludes owning any 'exotic' classic as the wallet must be very deep indeed for the new generation or breed of 'experts' who are ready to rifle it.

Living with a Shadow outside the UK, Australia or the States and possibly Germany is hard if your standards of performance and maintenance are high. The classic car world has changed so dramatically in the last 15 years to become a lifestyle and investment choice for so many of the well-heeled. This has greatly affected the attitude to maintenance costs.

I have had the Shadow in Warsaw for 10 years but it is sort of gradually, inexorably 'slipping' in smoothness and efficiency and is no longer quite the car I remember enjoying for 20 years in Central London. There it was always fastidiously maintained by the RR engineers who formed their own company in St. John's Wood when Kennings in London closed its doors.

Take this vibration for example. Can I or should I just live with it I ask myself?

Particularly when one lives with these elderly but original cars outside the UK, Australia, or the US is it really advisable, financially feasible or even possible to eradicate all the signs of creeping age?

Perhaps I should adopt the attitude I have to my own aging body and just accommodate to the obvious indications of the passing years and live with the decline, accepting change and patching when necessary in an emergency.

I suppose this is a very personal question but a complete or even partial rebuild of these wonderful Shadows to return them to something like their original state of performance with the low values they steadfastly maintain (with the assistance of pundits like Jeremey Clarkson who appears to hate them)? A rational idea? Why be rational? Owning classic cars is hardly that!

I think I may have to drive the car to Berlin where there is an excellent and experienced RR specialist with the legendary German attention to detail. To feel truly confident that the swapping of the Detroit joints has been done correctly I will need to do this I think despite your assurances it is 'straightforward'. I recognise the fantastic good intentions of Polish mechanics and they are brilliant in some areas of classic car restoration and maintenance (and as Spitfire fitters during WW II) but Silver Shadows and detailed knowledge of them is rather a different matter. Why would they know about them in detail?

This is an absurdly long posting but bear with me. It makes me feel better! I really have no-one here to discuss such complex Rolls Royce issues with and then of course there is the Polish technical language which is full of surprises and pitfalls.
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Omar M. Shams
Grand Master
Username: omar

Post Number: 400
Registered: 4-2009
Posted on Sunday, 15 June, 2014 - 09:05 pm:   Edit PostDelete PostView Post/Check IP

Dear Michael,
Your problem is not unique. I live in an environment similar to yours. We have many competent mechanics but they are not experienced nor are they able to troubleshoot anything on our cars.
They are happy to plod on doing anything you ask them to do for relative peanuts. So take advantage of that and let them do the hard work with you acting as their manager.

In your case, you will have to sit with your mechanics and talk about the problem so you can engage them towards solving the matter. These cars are not all that different to other cars - the laws of physics apply to our cars as they do to any other car.
There are a myriad of things that could have happened to the car over the years to get you to this state of vibration.
Get involved with your mechanics to troubleshoot the vibration even if it is the simplest suggestion ever (like - have you greased the nipples on the prop shaft?). Then use the forum to get your fellow enthusiasts to guide you towards the next step.

Help us by clearly explaining what you have done and what you are seeing as a consequence. You refer to Benoit in your previous posts - he is a great example of someone clearly articulating his problem and his attempts at solving the problem. He has had many posts becasue we are all willing to chip in and help. Just like we want to help you.
Your job now is to give us some meat to chew on. give us some background to the problem how it started, when it started, what affects it (temperature, number of passengers, tyre pressure etc) tell us when you last changed your tyres - in fact flood us with information and then sit back and read.....


Good luck.

Omar
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Paul Yorke
Grand Master
Username: paul_yorke

Post Number: 1209
Registered: 6-2006
Posted on Sunday, 15 June, 2014 - 09:39 pm:   Edit PostDelete PostView Post/Check IP

Michael, I feel for you. It is so nice when an owner wants the best possible maintenance for their car but so disappointing when they can not get somebody to look after it.

Once these cars get neglected they can accumulate such a large amount of faults that it is almost impossible to pull them back, let alone pull them back for a sensible price.

I recently picked up a new client that had just bought a Shadow II. Supposed to be a 7 out of 10! The customer was complaining of a vibration. As soon as I drove it I told the owner that it had a number of vibrations caused by a number of faults (they came at different speeds and different loads. Another couple during braking). I warned him that locating them will not be easy!!

The car was supposed to be a low mileage, well cared for example. Now a few months have gone by and it has become clearer that it was a car with problems that had just be used to death and then cast aside. (not to mention the 'tarted up' rust problems!)

Vibrations:
It already had new tyres - rebalance.
Trunions swapped over.
Outer UJ's. No feel of wear to the hand but once stripped there were visible grooves on them.
Prop Shaft UJ's (same as outer UJs) Lack of greasing through it's life.
Balance prop shaft.
2 x Rear hub rebuilds. Pads were seized - discs were knackered.(Vibration during braking.)
Two front rims with his tyres.
Two new tyres on the new rims.

One last vibration to go. Another rear rim to try tomorrow with his tyre.

With each job a vibration was cured but it was a long slog.

This along with diff mounts, torque arm mounts. Carbs with linkages that were completely wrongly set up causing one carb to do most of the work. Drivers wind noise. (The door had been caught at some point. Instead of hanging the door correctly, they had filled and painted to get the gaps looking right) :-( .

Never had a Shadow II with a drive train as bad as that. Next time I will do all the jobs in one go! You live and learn I guess.
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Michael Moran
Experienced User
Username: mjcmoran

Post Number: 19
Registered: 8-2005
Posted on Sunday, 15 June, 2014 - 09:50 pm:   Edit PostDelete PostView Post/Check IP

Thanks Omar for your thoughtful reply. Where are you living actually?

A couple of things. Unfortunately repairs are not cheap here anymore although relatively inexpensive compared to say Jack Barclay. Hence my remarks about the complexion of classic car ownership and maintenance changing greatly even in Poland.

Actually I have exhausted most of the more simple possibilities - really. New tyres, wheels balanced, wheel bearings checked, balanced prop shaft, checked oil in the Detroit boots often neglected in servicing, engine mountings checked,sub-frame mountings, 'Brillo pads' checked, universal joints properly greased and so on. Perhaps I should have said this. Hence my mention of the coupling flange. Much advice has come from my old engineer mechanics over the telephone in the UK. This quest to eliminate vibrations has been going on for a couple of years now.

Benoit's story is very familiar...

The next step is swapping the Detroit joints which I will do as the next stage in the process of elimination and let you know. many advisers think this is the main issue.

This did not actually solve Benoit's problem but we shall see with mine.

I am afraid that I simply cannot achieve the level of maintenance and performance I am still perhaps foolishly looking for and actually remember. I cannot seem to achieve this outside of the highly professional, knowledgeable and competent RR engineers one finds in the UK. Hence my need for a change of personal attitude but 't'aint easy'.

Sure the car is running and to the RR uninitiated rather well, even impressively, but so is my memory of the past glories, unfortunately. Owners of these cars tend to be perfectionists. Also I am not an engineer and vastly more ignorant of mechanical matters than many who own these cars and contribute to the forums. I could not really sit down and discuss anything with a mechanic except the simpler technical issues in Polish. It is my second language and difficult.

I really cannot judge if matters are being done as they really should be done. The Silver Shadow Workshop Manual and its directives and implications terrifies me to be quite honest.

Will keep you informed how I get on

Mike
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Michael Moran
Experienced User
Username: mjcmoran

Post Number: 20
Registered: 8-2005
Posted on Sunday, 15 June, 2014 - 10:06 pm:   Edit PostDelete PostView Post/Check IP

Thanks Paul and hi again

We have corresponded before on a couple of issues in the past, even this one I think.

My car has been carefully maintained pretty well regardless of expense while I lived in London (till 2005)and here too (with aforementioned reservations) during my 30 year ownership so perhaps this vibration will be easily solved by the trunnion swap.

Unfortunately for me I am very sensitive to changes and sounds in cars. Mechanics think I am a bit loopy when I bang on about something they cannot hear or feel themselves. However given time I am nearly always right and soon something needs fixing.

I am so tempted just to take the car back to the UK, pop it into P & A Wood, get their 500 GBP 'Diagnostic' followed by application for a mortgage or large bank overdraft and damn the consequences!

Not sure what my beautiful Polish wife would say and I do value (although not fear) that!

Best

Mike
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Omar M. Shams
Grand Master
Username: omar

Post Number: 401
Registered: 4-2009
Posted on Sunday, 15 June, 2014 - 10:11 pm:   Edit PostDelete PostView Post/Check IP

Dear Mike,
I live in Dubai.
The things that I have learnt to live with include asking myself questions like these:
Were the new tyres I bought stored properly or had they been stacked in a hot warehouse at the bottom of the pile? Is the balancing machine that was used to balance the wheels calibrated? were the wheels straight or did the tyre technician try to correct the problem of wonky wheel and out of round tyre in one balance assembly?

I would try to get a set of wheels from another car and try to eliminate the wheels in their entirity at this stage. The idea of swappinhg the drive shafts sounds like a good logical next step for you.

Rather than give up - keep trying all the little change until the car comes back to her former glory.

Good luck
Omar
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Jonas TRACHSEL
Experienced User
Username: jonas_trachsel

Post Number: 48
Registered: 2-2005
Posted on Sunday, 15 June, 2014 - 11:23 pm:   Edit PostDelete PostView Post/Check IP

Michael
I assume you are a member of the RREC and get their Bulletin along with the Advertiser. I remember having seen in the small advertisements a guy willing to travel: "semi-retired Motor engineer to work at your own premises, Silver Shadows my speciality". To fly this chap in to Warsaw might be a more cost-effective option to getting your SS to P&A Wood.
Just an idea...
Jonas
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Michael Moran
Experienced User
Username: mjcmoran

Post Number: 21
Registered: 8-2005
Posted on Monday, 16 June, 2014 - 06:25 pm:   Edit PostDelete PostView Post/Check IP

Thanks Jonas.

I have seen his advertisement many times but he also says the offer to travel is 'within 100 miles of Salisbury'. However I have thought of him before and will give him a ring.

The most likely problem for him would be travelling with heavy tools on an aircraft unless I can persuade a Polish garage to hire me a hoist and tools. But most good mechanics do like, often insist on, using their own things. However not an impossible idea with the contacts in my car club.

I was wondering what make and model of car that is not a Shadow has a drive train that most closely resembles the Shadow design and layout? BMW, Mercedes Benz, Jaguar, Land Rover and Bentley (recent models only) all have excellent service points here as well as more popular European and Japanese cars. As Omar pointed out the car is not absolutely unique in all its design aspects. Perhaps one of their engineers here could deal with the investigation. I have used the Citroen service point here to deal with the accumulators and brake hydraulics for example.

Perhaps someone could help with an answer?

At present I am still thinking the Berlin trip is the best bet. It is only 356 miles (573 kms) which by Australian standards is nothing much!The RR engineer who has set up business there years ago is recommended by the R-REC German Section. He used to be head of the workshop with the large past German RR dealership Krauthahn in Berlin for many years until they gave up on servicing the older RR models. They now only service modern Astons, Jaguar, Land Rover and Bentleys.

However time and convenience is the main issue for me. I am not a pensioner (although certainly of pensionable age!) sitting around looking for occupations to fill the time so this trip to Berlin would need to be carefully planned.

Thanks again.
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Paul Yorke
Grand Master
Username: paul_yorke

Post Number: 1210
Registered: 6-2006
Posted on Monday, 16 June, 2014 - 07:24 pm:   Edit PostDelete PostView Post/Check IP

Hi Michael,

I would avoid main agents :/

Most of the drive train is pretty standard.

Have you managed to grease both prop UJ's. Tricky but a must.

The trunions are unusual, but pretty basic engineering.

With care and patience they are easy to swap.

Ensure they are removed in their horizontal plane with a hand holding the mushrooms in place on both ends of the pin.

Reassemble them with grease to help hold them together.

The flanges that bolt to the diff need swapping to keep them on their correct side. But it's just a circlip holding them on.

If there is a excessive leak from either diff output shaft, it would be a good time to change them.

I would 'now' be very tempted to change the outer UJ's whilst the shaft is off. Usually I would have just felt for notchiness or stiffness. :-(
A visual check is a must.

Feel inside the trunion for a ridge where the ball runs, this is what causes the judder.

I also travel abroad to do on site repairs, but usually as a working holiday to somewhere sunny . Tools and parts are heavy and a big problem. I usually take my wife - for company, not for her luggage allowance I hasten to add.:-)

My geography is a little jaded it seems. I had a couple of enquiries to do some work near Bordeaux which would involve driving over - just googlemapped it to see if an extra leg would be feasible - wow Warsaw is a long way away!
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Michael Moran
Experienced User
Username: mjcmoran

Post Number: 22
Registered: 8-2005
Posted on Monday, 16 June, 2014 - 09:23 pm:   Edit PostDelete PostView Post/Check IP

Thanks Paul

Yes I am a fair way from the UK but only 2.25 hrs by plane. Warsaw is a long way east by road however.

When travelling by car to London (not often)I usually catch the very comfortable overnight Scandanavian DFDS ferry from Harwich to Esbjerg in Denmark, drive the short distance south to the motorway at Hamburg, then east to Berlin, on to Poznan then to Warsaw on excellent new motorway all the way. Cuts almost 700 miles and much fatigue off the road trip from the UK.

By the way my car club has quite a big expat businessmen contingent and we are all struggling with our English classics! One or two restoration companies here with good mechanics are top notch and comparable to UK standards but only on Astons, Jaguars, Healeys, Triumphs, MGs and so on. RRs and Bentleys are not generally taken on...

To feel confident of a 100% proper job having been done I think Berlin is the answer despite your helpful details. The vibration may not even be the trunnions.

http://www.rolls-royce-service.de/

Over the last 10 years here, even with regular careful servicing according to the Service Manual, I am sure various other matters might have to be attended to concerning the aging process which has little to do with mileage covered...

You know if I am having this sort of issue in an EU country with an old relatively simple car I cannot help wondering what will eventually happen to all those new supremely high tech Bentleys and RRs going out to China and Russia. I cannot imagine maintenance and repairs of the correct sort is a priority or even possible except in the capital cities. I may be entirely wrong of course.

Mike
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Bob uk
Unregistered guest
Posted From: 94.197.122.79
Posted on Tuesday, 17 June, 2014 - 05:59 am:   Edit PostDelete PostView Post/Check IP

Propshaft vibs will be of a different frequency than the drive shafts because of the final drive ratio

In top gear the prop vibs will be at engine speed or a multiple


The drive shaft vibs will be at wheel speed

Check prop shaft balance weight is there and not fallen off

Note that the drive shafts are not balanced

(Message approved by david_gore)
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Richard Treacy
Grand Master
Username: richard_treacy

Post Number: 3025
Registered: 4-2003
Posted on Tuesday, 17 June, 2014 - 08:04 pm:   Edit PostDelete PostView Post/Check IP

Hallo Michael,

Good to hear from you again.

Not much to add to this really, but a straightforward diagnostic may be appropriate.

If you were to set the levelling system to its lowest level (i.e. so that it never lifts the vehicle) you can do a simple test. Drive it and note the vibration intensity. Then load the boot with 100kg or more (several crates of Okocim may do the trick) so that it is right down in the tail. Drive it again. If the vibration increases markedly then you may suspect the Detroit joints. If there is no change you may suspect the propellor shaft or flange.

The wild card is always a broken Woodruff key in a hub, not unheard of but a very rare cause. As with the propellor shaft, it would not cause a change in vibration intensity with the height test.

RT.
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Richard Treacy
Grand Master
Username: richard_treacy

Post Number: 3026
Registered: 4-2003
Posted on Tuesday, 17 June, 2014 - 08:12 pm:   Edit PostDelete PostView Post/Check IP

ps: Bill Coburn was the one who first showed me a broken hub Woodruff key and that was on a 1974 Silver Shadow around 1980 at his earlier Canberra home near ours. The vibration had confounded everyone until he dismantled the hub and Hey Presto ! He whinged for months about the 2,000 lb-ft torque required to undo the hub nut.

RT.

RT.
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Michael Moran
Experienced User
Username: mjcmoran

Post Number: 23
Registered: 8-2005
Posted on Wednesday, 18 June, 2014 - 12:48 am:   Edit PostDelete PostView Post/Check IP

Hi Richard!

So you are still contributing. Excellent news.

I am fairly sure it is the Detroit joints as I have done a modified version of your suggested test with three hefty Poles seated in the back! Vibration was markedly worse. The Woodruff Key is a new one which I shall certainly hold in mind.

By the way, my Polish mechanic after strengthening the rear cross member according to your excellent instructions remained skeptical until not long afterwards a panic call from a Corniche owner who had dropped his entire rear suspension onto the highway. I drive with confidence!

I will let the forum know what actually transpires in Berlin. A few other adjustments may need to be made to the car so I think the trip and financial outlay will be worth it.

Incidentally the MG TC is now fully sorted and greatly admired. 'We all have our little weaknesses' as one R-REC member commented when I told him what other classic car I owned. Such fun this iconic English sports car. Incidentally a beauty appeared in 'Foyles War' driven by a gentleman army officer cad and another by a lady crime writer appeared in 'Poirot'. A car most suited to English country lanes in stylish hands.

Great to hear from you

Mike
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Geoff Wootton
Grand Master
Username: dounraey

Post Number: 428
Registered: 5-2012
Posted on Wednesday, 18 June, 2014 - 01:42 am:   Edit PostDelete PostView Post/Check IP

Mike

There was a recent UK television programme featuring the history and restoration of an MG TC that you may be interested in. It is on youTube:

http://www.youtube.com/watch?v=k19EzZl0unM

I always download the high definition version rather than watch online. The programme is presented by a UK actor called Philip Glenister who is fairly disparaging at first and then is finally won over by this superb car. I have never owned one but a friend of mine did. I was surprised how "tight" it felt on the road. I was expecting rattles and such like. None of it, it was great. I don't know whether the lack of a fuel gauge came as standard, but on my friends car there wasn't one, just a red warning light that illuminated on the dashboard indicating it was time to fill up the tank. I love the idiosyncrasies of these old cars.

Incidentally, I too have owned an XK150. It was a 1959 drophead and I too would have liked to have kept it. Not always possible as circumstances change.

Geoff.
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Michael Moran
Experienced User
Username: mjcmoran

Post Number: 24
Registered: 8-2005
Posted on Wednesday, 18 June, 2014 - 03:17 am:   Edit PostDelete PostView Post/Check IP

Hi Geoff

Thanks a lot. I had been looking for this.

Although this is wandering quite off-topic and not RR technical in the slightest bear with me if I just say a well-restored MG TC is the most affordable and fun pre-war driving experience on the planet.

They are forgotten by too many who hanker after absurdly over-priced pre-war exotica like Astons, Lagondas, Talbots, Alfas, Rileys, Squires and so on and are seldom restored properly by folk with real money to spend.

A great pity as they were the essence of the British pre-war sports car concept for everyman. Yes, they were designed before the war as the TA but manufactured immediately after as the TC. People forget this.

The TC has always been a real favourite among Australians who as we know from this forum understand the very best in motors!

My MG TC in action in a Polish forest
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Larry Kavanagh
New User
Username: shadow_11

Post Number: 10
Registered: 5-2016
Posted on Tuesday, 30 August, 2016 - 05:11 am:   Edit PostDelete PostView Post/Check IP

Hi Michael, Wondering if you managed to solve your vibration problem. I'm experiencing a similar issue when accelerating and suspect that it is caused by engine mounting deterioration but I've put the diagnosis on the long finger due to more immediate mechanical matters that need to be addressed, Regards, Larry
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Martin Taylor
Experienced User
Username: martin_taylor

Post Number: 40
Registered: 7-2013
Posted on Tuesday, 30 August, 2016 - 06:57 am:   Edit PostDelete PostView Post/Check IP

Like others I have chased vibration problems, replaced diff mounts etc etc, finally cured it by raising the height of the rear of the car to compensate for worn springs, now when the car squats on acceleration the shafts are straight and smooth, if it gets worse with load or up a steep hill it is probably a sagged rear end. Move the height linkages to get the end up about an inch and go for a drive, you will soon know. I then added spacers to the spring mounts for a more proper fix.
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Geoff Wootton
Grand Master
Username: dounraey

Post Number: 1380
Registered: 5-2012
Posted on Wednesday, 31 August, 2016 - 12:44 am:   Edit PostDelete PostView Post/Check IP

I had the opposite problem. When I replaced my rear springs I introduced a vibration issue when accelerating 35 through 50. My guess is the drive shafts had worn as the rear end gradually sagged over the years, so when the new springs changed the angle, the vibration started. Things have improved as the new springs have bedded in however I will try the "switch half shafts" trick when time allows, to see if I can completely eliminate the slight, but annoying vibration.

Geoff
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Larry Kavanagh
Experienced User
Username: shadow_11

Post Number: 11
Registered: 5-2016
Posted on Wednesday, 31 August, 2016 - 05:53 am:   Edit PostDelete PostView Post/Check IP

You may have pointed me in the right direction Martin, my rear springs are indeed sagging. The vibration only happens on acceleration, this is when the rear end drops, so it could well be caused by the saggy bum phenomenon. I thing I'll add rubber spring assistors and see if that works as a temporary solution. Won't be getting around to this fix for a while but I'll report back with my findings at some later stage, Thanks, Larry
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Carl Heydon
Prolific User
Username: car

Post Number: 109
Registered: 2-2004
Posted on Wednesday, 31 August, 2016 - 07:03 am:   Edit PostDelete PostView Post/Check IP

It is not a fun job swapping shafts especially lying on ones back but I needed to change the boots so while I was there...
Imagine my joy to drive it and realize they had already been swapped and now I had more noise. One day I'll swap them back
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Geoff Wootton
Grand Master
Username: dounraey

Post Number: 1381
Registered: 5-2012
Posted on Wednesday, 31 August, 2016 - 07:36 am:   Edit PostDelete PostView Post/Check IP

Carl

That had occurred to me, but until I try it I will never know.

I had an abortive attempt some time ago but could not remove the circular flange from the diff unit. This is the flange that is held by six 7/16 nuts. I have to admit I did not try too hard to free it, resorting mainly to tapping the edge until I decided not to proceed.

Did you have any trouble removing these? Did you have to resort to lump hammer and chisel or did your's free off quite easily?

Geoff
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Carl Heydon
Prolific User
Username: car

Post Number: 111
Registered: 2-2004
Posted on Wednesday, 31 August, 2016 - 06:31 pm:   Edit PostDelete PostView Post/Check IP

NOT free and easy. From memory a fine blade tapped round the joint but it was quite reluctant. I remember that bit.
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Paul Yorke
Grand Master
Username: paul_yorke

Post Number: 1624
Registered: 6-2006
Posted on Wednesday, 31 August, 2016 - 06:36 pm:   Edit PostDelete PostView Post/Check IP

Feel inside the trunnion cups for a wear indentation, it's usually a gentle dip, not a ridge.

If you remove all but two opposing nuts - which you should remove to the end of the thread, you should be able to lever between the cup and the nut, no need to chisel at the flange.
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Geoff Wootton
Grand Master
Username: dounraey

Post Number: 1384
Registered: 5-2012
Posted on Wednesday, 31 August, 2016 - 11:34 pm:   Edit PostDelete PostView Post/Check IP

Carl/Paul

This is encouraging. I remember some time ago Benoit said the ring on his car came off quite easily which lead me to fear that a previous owner may have used a jointing compound on my car (araldite perhaps). I was kinda joking about using a chisel between the machined surfaces (or was I?). I've now got a handle on how to proceed when I do this job.

Thanks

Geoff
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Martin Taylor
Experienced User
Username: martin_taylor

Post Number: 43
Registered: 7-2013
Posted on Thursday, 01 September, 2016 - 07:14 pm:   Edit PostDelete PostView Post/Check IP

To test if it's saggy springs you can move the height control linkages (assuming your height control is functioning), this is as simple as loosening two 7/16 nuts and sliding them up the slots until the the shafts are sloping down towards the wheels, this means they should be straight during acceleration, you can always attach a camera under the car to watch or record it, if there is a vibration you may be able to see the runout.

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