| Author | Message | ||
     John Dare Unregistered guest Posted From: 144.138.194.110 |
Most Shadow owners would be aware of the potential for the Final Drive cross member (which supports the differential) to break away from the underbody mounts, sometimes with spectacular and expensive consequences. Most of these members, would, I suspect, have been modified by now, with structural reinforcing in the body of the member itself, and at the outer mounting attachment points incl.reinforcing plates forward of the trunk/boot floor pan. The last price I recall for a genuine new part was close to A$2000, should one need to buy in the event that your own was damaged beyond repair if it fell onto and was dragged along the road. Only recently, I was talking to a long time Shadow owner (30 years) who told me that when this happened to him he was unable to obtain the part ex R-R (allegedly no stock at the time) BUT lo and behold he had a "expert" actually MAKE one for him. You mean "he (the "expert") REPAIRED/MODIFIED your "own" damaged member",said I, politely. "NO..(said this gentle though somewhat impressionable soul) "he actually MADE me a brand new one!" and.. and.. its STILL there in the car at this very moment in time; as we do speak. Not wantng to soil my "Nike" outfit by slithering underside to view this custom made masterpiece, I had no option but to accept his "story" and move on, wondering WHO was the artisan/boy genius/"expert" who managed to cobble up some semblence of a Final Drive cross member ENTIRELY from bare pieces of steel/alum.whatever. Does anyone know where I can buy one of these custom made/better than original(alleged) cross members and if so, what is estim. price and delivery time? | ||
| Mark Peacock Experienced User Username: takemehomejames Post Number: 6 Registered: 4-2004 |
John, is the crossmember you talk about, the support crossmember (that is mounted from the front of the final drive) or the Main crossmember (mounted between the wheels)?. Ive had dramas with the support member on my "james" 31689.I found that the previous owner did'nt know how to handle a trolley jack correctly, and put a crease in the middle of the member, which weakened the member . In turn, awaiting a sudden acceleration, then bang, clunk clunk clunk (followed by a tow truck). After trying to straighten the member (to no avail) I managed to buy one new for under $1000. While i was there, i replaced all mounting brackets etc. The point to all this is, i've noticed that the Shadow's chass 50000 and over and spirits have an aluminium final drive support unit. Maybe they can be used instead of the flimsy steel unit... Mark | ||
| John Dare Unregistered guest Posted From: 144.138.195.4 |
Yes, Mark, I am referring to the cross member to which the differential is actually supported BY and attached TO. "Legend"(another one!)has it, that some world "expert"(right here in Australia!) has actually cobbled together a replacement member, starting out with no more than random pieces of steel/aluminium etc. What I am trying to do is locate the brilliant, mastermind designer of this potential eighth wonder of the industrial world, so that I might place my order and get the "best"! | ||
| Bob Unregistered guest Posted From: 80.4.224.7 |
The cross member would not be that hard to make . Any skilled engineering craftsman could make one. I hve made similar things many time with simple hand tools welding equipment and a pistol drill. (Message approved by david_gore) | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 401 Registered: 4-2003 |
I beg all you Shadow owners to take urgent action. If a failure happens at speed it could be literally fatal. It seems that these cars are now of an age when the risks are increasing rapidly. I attended the annual RREC Greasy Finger Day two weeks ago. We take over a modern Swiss roadwortiness test facility for the day and use all the fancy test gizmos. I took the opportunity to ask owners about the Shadow crossmember failures and took photos. There are two failures which WILL eventually occur unless corrected: 1. Cars prior to 1975: the crossmember itself fails unless strengthened. 2. ALL SILVER SHADOW AND SILVER SHADOW II cars: the car body tears away as mine did. A steel plate is needed in the boot, especially on the left hand side. Both failures are rather common and usually very expensive to repair: usually the left side driveshaft, and sometimes the crossmember and the final drive itself are cactus. The crossmember itself was the more common failure in the past. The two screws bolting each resilient mount onto the crossmember tear out. The second failure is a more recent development with age, so watch out. I spoke to at least 6 people on that day alone who have suffered this failure !! Please lift up your carpet and have a look at the front corners to see if the plate has been fitted. If not, have one fitted pronto: it's a cheap job if you do it before a failure occurs. I can send anyone interested more photos of both modifications, and unmodified crossmember, and my own hand sketches from a few weeks ago. The mod is very easy to see in both cases. No jacking or tools are required. This is all due to recent first hand experience with the second type of failure by the way. We have finished the repair: the second type (boot floor failure). Fortunately, both failures usually occur at the traffic lights when there is about 10 times the torque available at the back axle than at highway speeds. However, just like the pitman arm failures, you acn only imagine what a failure at speed would cause. A colleague saw a Shadow upside down in a ditch by a very straight section of uncrowded Autobahn near Prague a few weeks ago. We can only imagine what caused that. Plate in boot  Modified crossmember  Unmodified crossmember  | ||
| Mark Peacock Prolific User Username: takemehomejames Post Number: 35 Registered: 4-2004 |
richard, could you send me some of those drawings/photo's you mentioned. Do you think this is a corrosion issue for the failure or just plain fategue ?? Thanks djbartman@dodo.com.au Mark. | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 404 Registered: 4-2003 |
I have sent them to you. These are both straightforward fatigue problems. Our car has no rust at all anywhere and has never been in an accident. If you look at the parts catalogue, you will see that North American cars only, from chassis 15,434, at least used larger washers inside the boot. That was a great improvement, but a steel plate is much better. Our crossmember has never failed, but was modified by York Motors around 1977 when the crossmember failures first became epidemic. The boot sheetmetal failure has only popped up in recent years and is becoming rife. Both failure types were programmed to occur. The boot failure caught me completely by surprise as I had never heard of it before. If you look at the washer arrangement, it is obviously a very weak setup. I shall write some more for on this for David Gore tonight. RT. | ||
| Ralph C. Brooks Unregistered guest Posted From: 12.219.243.3 |
Me too, Richard. Thanks, Ralph SWII LRL40634 (Message approved by david_gore) | ||
| Robert Chapman Prolific User Username: shadow Post Number: 94 Registered: 5-2003 |
Hi Richard, As you have said the fatigue failures on these cars is increasing as time goes by. We are spending more and more time during sevice inspections looking for an ever growing list of possible problem areas and components. Our on car crack testing program of pitman arms has identified THREE cracked arms in the last 6 weeks.This is starting to get scary. | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 405 Registered: 4-2003 |
Hi Robert, This looks really grim indeed. What do you use as replacements ? Our car, SBH13247, has the final type of steering box before the Silver Shadow II: the third series was introduced at chassis 11216, and the second at 6429. The replacement Pitman arm supplied to us was different from the original, so I am hoping that the problem was cured with that one. Have you noticed that the replacements are different, and have you noticed a pattern of failures in any particular chassis number range ? I must admit, it makes sense to me to secure a source of machined steel replacements, from Poland for example, as the cast ones seem marginal at best in this application. Regards, Richard. | ||
| David Gore Moderator Username: david_gore Post Number: 324 Registered: 4-2003 |
Hi Richard & Robert, Can you please enlighten me about the manufacture of the Pitman arms - I would be EXTREMELY concerned if they were cast or machined from solid given the potential for problems from casting defects and inappropriate grain flow - I doubt R-R would ever accept these forms of manufacture for a critical safety item. For this reason, I would be very apprehensive about using after-market parts that have been machined from solid bar as at least 4 points of serious weakness will exist around each boss due to grain flow orientation. The main reason for using a forged component at higher cost is to ensure radial grain flow around the boss. Robert, could you please post a picture of one of your recent discoveries or email the image to me and I will post it for you - please do not post to me as I have changed addresses; if you need a postal address please email me. | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 406 Registered: 4-2003 |
David, You are surely correct: sorry, they must be forged. Even so, such widespread failures are alarming. RT. | ||
| Robert Chapman Prolific User Username: shadow Post Number: 95 Registered: 5-2003 |
Hi Richard, The new genuine parts we have been supplied are all of a strengthened design.And they are forged as was the original. The cars were 1973,1974 and 1976 models. They have all cracked in exactly the same position,fortunately they were all detected before they broke. Incidentally I have had 2 break on me,admittedly both whilst I was maneuvering slowly.I hope the next one does not conclude in the same manor as the car you mentioned in Switzerland. With the cost of manufacturing and stocking the parts that we already make(nearing 50 items)I could not even think about having the arms made,(all our parts are by commercial necessity fast moving) although I would wager they could be made at a far more reasonable price than that being charged by CREWE parts. In my opinion the least they should be doing is supplying the "superseded part"(which I believe to be a recognition of the faulty part) at NO CHARGE since they have not had the expence of a RECALL. | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 407 Registered: 4-2003 |
Robert, I understand that, until the end of the 1980s anyhow, Crewe did supply replacement Pitman arms free of charge. I even heard of some sort of class action in the UK over this prolific failure. When ours cracked and split open enough to slip on the splines in 1999 or 2000, there was no talk of a free one. I think it cost around $800, which was not too shocking. As you note, it is of a strengthened design. Fortunarely, the Pitman arm is stressed many times more when manoevering, so is almost certain to fail then and not at speed. Small comfort. How about a bit of spirited driving up a mountain pass in a car seldom manoevered ? I shudder to think. The same applies to the final drive crossmember. | ||
| Patrick Lockyer. Frequent User Username: pat_lockyer Post Number: 30 Registered: 9-2004 |
Time to check my mounts after some towing with caravan and the extra wieght of lpg. This is the first signs of a problem, movment shown on the resilient mount. problem is i have to take the lpg tank out to do the mods but it is a must before to long.  | ||
| John Dare Unregistered guest Posted From: 144.138.194.182 |
This area has historically been the first area to fail, when ambititous souls have entered Shadows in trans continental endurance/trial events etc. As for the rather undignified process of towing a "house" on wheels, or in my case, a horse float/trailer, such tasks should be assigned to an appropriate vehicle, such as my Range Rover or the like. My Rolls or Bentley?. I think not. (Message approved by david_gore) | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 412 Registered: 4-2003 |
John, You must take the credit for starting this thread. When I read your first post for the first time, I thought "yeah, yeah, that's old hat. Ours was rectified decades ago.". Reading your post again, I see you mention: "with structural reinforcing in the body of the member itself, and at the outer mounting attachment points incl.reinforcing plates forward of the trunk/boot floor pan. ". I guess you warned us: I didn't take in that the boot needed a reinforcing plate - I assume that is what you meant by the outer attachment points. Does your Shadow have both mods (crossmember and boot) ? If so, a picture of the boot plate would be useful. It's pretty frightful when one lets go. One let go here at the local agent's a few months ago while driving it gently onto the hoist. Very embarassing indeed. Thanks, RT. | ||
| John Dare Unregistered guest Posted From: 144.138.194.103 |
Thank you Richard. It would be expedient (as it is tempting) to take "credit" regarding the reinforcing of the boot/trunk floor of Shadows, in the area where the bolts locate and secure the final drive member. Honesty and due modesty must prevail, hence I concede it was the experienced John Vawser who alerted me to this (additional) requirement. I subsequently learned that Robert Chapman also performed that additional modification in order to achieve the best possible integrity of the final drive and the security of its location. (Message approved by david_gore) | ||
| Kevin Lagden Experienced User Username: kevin Post Number: 17 Registered: 7-2009 |
I am beginning to pick up on this thread as I am interested to learn more about the strengthening of the crossmember mod. I notice Richard Treacy seems particularly up to speed and would appreciate the detail on how to do this mod. Mine is a 1975 Shadow SRH 19305 and upon a quick check in the boot there seems to be no plates as per the picture on this thread. Need I worry as the rear sub frame mountings will be attended to next year. I would rather get it sorted now than wait for an expensive repair. Please send all available details on how to fix the issue. Thanks for the assistance Kevin | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 2031 Registered: 4-2003 |
The article is not very new, but is still up-to-date. http://homepage.swissonline.ch/Richard_Treacy/FinalDriveCrossmember.html The trouble with these things is that the roof doesn't leak until it rains. As Michael has pointed out, having the job done before it fails will obviously prevent disaster. As a minimum and interim protection, putting plates in the boot is cheap and easy to do until for some other reason more work is required in the general area. RHT. |
