Most Morgan owners know about the "Sliding Pillar" designed by HFS Morgan back in the early 1900s and that it is still used to day. This is just one of the items that makes this car near and dear to us.
|WEBMASTER NOTE: Damper blades were discontinued by Morgan in late 2007.|
There are 3 unique items to the Morgan suspension: the bushings, the damper blades and the one-shot oiler. Replacing the bushings will require the rebuilding of the front end. (See the article by John T. Blair - Rebuilding the Front End) The damper blades can replaced without totally disassembling the front suspension.
Bob Nogueira's explanation of how the front end design can cause the front wheels to wobble and how the damper blades help correct it is the best I've seen.
"The Damper Blades were not fitted to three wheelers I believe because the large wheels, light weight, and low speeds did not result in front wheel shimmy.
As the spindle moves up the kingpin over a bump, the spring will have a twisting motion, this is relayed to the spindle and results in a slight turning of the wheel. If this occurs at a certain speed. It sets up a harmonic bounce which becomes a violent shimmy. This usually occurs at between 55 and 65 mph. The damper blade is bolted to a bronze plate fitted between the spring and spindle and, via the blade, is held to the chassis. Thus the spring can rub on the bronze plate and move but the plate is held still and none of the springs motion is transferred to the spindle. Since the spindle moves up and down the length of the blade can not be fixed. The blade is held to the chassis by being sandwiched between two flat bars so that the blade can move in and out. At each end of the approximately 1" by 4" bars are shims which are the same thickness and material as the blade. These are positioned and pressed up to the blade's side as guides and the bolts hold them tight so they can not move fore or aft thusly preventing unwanted (side to side) lateral movement of the blades.
Both the shims and blade wear since the blade rubs on the shims every time the wheel moves up or down. As the blades and shims become worn, their edges lose the height necessary to act as a stop and they pinch rather than guide (stopping movement entirely). To test for wear, grab the blade and push forward and back. If a click or movement can be heard or felt the shims need to be pushed tight against the blades. There should be free movement in and out, from the center line of the car, but no movement otherwise. I check mine every time I grease the car, and adjust the slack out."
The One Shot Oiler
This is one of the more intriguing (and sadder) stories of Morgan design. It remained unique only to Morgan as part of the front suspension from the 1950s to 2002 when it was finally removed. The manuals of the day suggested that the front suspension be given a regular shot of oil from the one-shot pedal immediately at start up every 100 mi. In fact, it did and can not lubricate the suspension as its kingpin exit hole does not reach the reservoir section within the stub axle. Others suggest that it is there to lubricate the damper blade plate, but the MMC was quite clear in their 1920s articles that this plate was a FRICTION damper. Oil would prejudice that. In any event, all stub axles grease that plate automatically from a drilled passage coming up from below.
The only thing that testing and experience has proven is that use of the one shot oiler;
1. can dangerously foul the brakes
2. cover that area of the car with dirty oil
3. offer the opportunity for a broken one shot oiler valve and/or lines and void the car in minutes of motor oil..to disastrous effect.
4. Dirty the floor around it.
WATCHPOINT: Replacement of the old oiler system with a grease zirk sadly makes no sense at all. The older passages are not made for the passage of grease and the grease will NOT go far enough down to reach anything of significance. The exit hole exits too high to serve the stub axle grease reservoir. The result of using the oiler passage to feed grease is to create grease gobs next to your brake disc.
Why is the one-shot oiler there? It was placed at the insistence of Peter Morgan (NOT HFS!) who had seen something similar with Bentley (different design). Though there was advice against, one does not argue with the boss, especially a well-loved one. The oiler was removed as soon as internal diplomacy allowed in 2002. Few, if any experts or dealers had suggested its use for decades before. It was removed completely.
WATCHPOINT: Once you are removing the system, do it right. Remove the oiler lines to the junction on the bulkhead. The pre-1998 cars feed the pressure gauge from the oiler juntion at the bulkhead. You can replace the gauge with its electrical version. Both VDO and Smiths oil gauges come in an identical-looking electtical gauge that functions by electrical signal rather than an oil feed.That removes all risk. Or, if you wish to keeping the mechanical oil pressure gauge, plug the feeds to the oiler systyem at that junction with bronze threaded plugs. Even so, you would be to change the feed to the junction to an Aeroquip line. There are many reported incidents of that nylon oil line breaking or melting with sad result.
In 2007 the MMC replaced the damper plate and blades with steering races (bearings) copied from the systems of designed by John Sheally, Peter Mulberry and popularized by eMog in 2001/3. However, the MMC stub axle design proved to inadequately replenish bearing assembly with grease. To assist in this task, they once again drilled passages down their kingpins to feed the bearing housing, a wider one that would specifically feed their bearing system with a large grease nipple atop the kingpin. Meanwhile, the aftermarket systems noted work well without this passage. Just grease the lower grease nipple normally and wait for the grease to appear at the edge of the bearing cup.
See Front Suspension Lubrication
The only remaining part of the front suspension that can contribute to the vibrations is the steering box and the tie rods.
Borrowing a section from Fred Sisson's book (Notes from a Morgan Garage), he discusses a problem with the tie rods:"I found a source of play on my +4 steering. It is a simple adjustment to eliminate it. The Pitman arm (on the steering gear box) transfers it's motion to the tie rod (the rod between the front wheels transverse rod) via the drag link. The ball end on the drag link fits into a clamp-on fitting on the tie rod.Morgan Classics have had 4 different steering assemblies (at the time of this writing). The first 4/4s were similar to that on the Trikes. They simply had a reduction gear mounted on the steering column. This was quickly change and a Cam Gear then a Burman worm and nut box was installed. This was used up until the later 1980s when the steering box was changed to a Gemmer box.
I noticed that the first motion of the transfer rod would twist the tie rod about 1/8 of a turn before it actually moved the tie rod. The ball tie rod ends allow this rod to twist that much.
By loosening the clamp and rotating it on the tie rod slightly, the twisting motion was eliminated, thus tightening the steering action some.
I've checked a friend's +4 and found the same problem. You might want to check your car too. Just have a friend move the steering wheel while you watch the action of the tie rod. With a little experimenting you will find a position for the clamp that will not twist the tie rod.
Fred Sisson 1992"
The Burman box has an adjustment for loading the worm. Also check that the bolts on the top of the steering box have not vibrated loose. To check the worm loading, jack up the car and disconnect the Pittman arm (the big heavy steel arm coming from the bottom of the box) from the drag link (cross bar that connects to the tie rod). Carefully turn the steering wheel from lock to lock. There should be just a slight (ever so slight - about 12 in. pounds) increase in the force required to move the steering wheel through center. If not, loosen the locking nut on the screw adjuster located on the top of the steering box. Turn the adjusting screw slightly, tighten the locking nut and re-test. Once there is some resistance felt, no further adjustment is required.
Mating New Bushings to the Kingpins (updated 2014)
by Lorne Goldman
Morgan stub axles are not made to a dimensionally consistent standard. In welding the kingpin tubes to the axles, the Factory warps the kingpin tube and they do not correct the anolmalies they create. Ergo, except for Devol-bushed cars made between late 2001 and 2006, each tube is can be different. Instead of correcting the tubes to a standard (which would require a one time honing or reaming of the the tubes themselves to a common ID and matched alignment of both ends). Without a common ID and alignment, resultant fit bushes cannot be used and we are forced to aline the bushes each time we replace them a sad waste of time fraught with the possibility or making an error.
If course it would be much safer, easier and less costly to simply press bushes in and expect, automatically, a correct clearance and/or alignment of top and bottom. But, as Morgan has planned it, you can have one bush askew one way and the other end askew another way along with varying clearances after the busshes are force-pressed into the lopsides tube, inconsitent ID tubes, making the kingpins bind and sieze. So properly sizing and aligning new bushings to the kingpins is absolutely key to the success of the job. So once the old bushings have been removed and the new ones forced in, they will have to be mated (aligning the bushes with each other and the kingpins and also machined so that the interior diameter of the bushes has the right clearance for the kingpins). This will require either that you purchase some special tools aka a line reamer) or find a machine shop that will do the work with more sophisticated equipment, (computerized laser guided honer.)
These are the two methods of obtaining a correct bush fit. One is to use a line reamer, the other is to have them honed. The consensus of opinion is that the honing is preferred as a better and a computer-consistent precision fit can be attained every time. I have not noticed a difference. As well, honing allows for improved lubrication of the bushes on the same principle that encourages the honing of engine cylinder walls. Knowledgeable owners simply use hardchromed kingpins and forget such esoteric niceties. I once had mine done at our nearby a machine shop with a laser-guided Sunnen honer. $20 per axle. However, I admit to using a line reamer whenever I am faced with bronze bushes....much more convenient.
Hard Chromed Versus Stainless Kingpins(1998, updated 2014)
by Lorne Goldman
The variance in front end lifetimes depends the kingpin material and the frequency and quality of owner care. I recommend the front end be cleaned and PROPERLY be greased (properly) every 1500 miles.These figures come from feedback in my archives, gleaned from personal and forum correspondence. Be very careful on who you choose to redo your front end installation and the source of the hardchromes. Metal bar stock comes in a variety of grades and features. It is not only the hardchroming that produces the legendary longevity, it is the quality of the metal under the plating. If it is too soft, the plating wears quickly, like the factory's stainless pins.
Negligent or sporadic care Proper Care MILD STEEL (MMC) 3000 to 10,000 miles 25,000 to 30,000 miles STAINLESS STEEL (ORIGINAL MMC) 10000 to 15,000 miles 30,000 to 40,000 miles * HARDCHROME 25,000 to 30,000 miles 100,000 miles to indefinite
WATCHPOINT: I can assure you that the Factory stainless kingpins will wear before the bush materiel no matter what you use for the latter. Hopefully, the company will choose a better quality of stainless over time. Additionally, from the longevity point of view, it does not matter what bush materiel you favor, though different types have garnered the fanatical devotion of religious zealots. As long as you use the proper hardchrome bar stock, within a proper installation, the longevity of your front end will satisfy the most prolific driver. So you can ignore all the web advice to use only the sacred secret product found in Lost Incan cities with an installation involving ritual chanting and the sarcificial blood of innocent virgins. This stuff is not mogic nor rocket science..it is merely misunderstood for a vary long time. Whatever you do, avoid Suplex...a $2000 method to cure a $5 problem.
For years, it was mistakenly thought that road grit caused the premature wear..always in the lower bush. The theory was that water and the grit formed an abrasive paste that entered the area between the kingpin and bushes and destroyed one or both. This may well be a contributing factor, but there has never been any empirical proof. In 2003, with the advent of Devol bushes, the causes for bush wear became crystal clear. The lower part of the mild steel kingpins quickly rusts at the bottom, where water accumulates in idle periods. The rusted exterior surface of the kingpin then acts as a rasp, grinding away at the bush. Stop the kingpin from rusting and the lifetime of the bush, of whatever materiel, is multiplied enormously. That is why the popularity of hard chromed kingpins has soared in the last decade, spread by eMog forum testing and there universal success.
Actually, hardchromed kingpins have a very long history in the community. They were installed by enthusiasts as far back as the 1950s. I have been using them since 1997. By chance, in 2004 I discovered a fine fellow in Birmingham (the UK one) and spent a lovely afternoon with him. He was an 85 year old Morgan enthusiast and retired master machinist. He had bought a Morgan directly from Peter in 1958. After developing the Morgan wobble after 13,000 miles, he examined the wear and then made himself some hardchrome kingpins from centerless ground (to make the surface perfect) 1 inch bar stock. He slipped them in and never needed to redo his front end in his whole tenure with the car and he sold it..in 1991 with 95,000 miles!
Hardchrome, also known as industrial chrome or engineered chrome, is used to reduce friction, increase wear time and provide a corrosion barrier. Unlike Decorative or Show chrome it is very hard, measuring between 66 to 70 HRC. Hard chroming also tends to be thicker than a decorative treatment, typically ranging from 0.075 to 0.25 millimeter (0.0030 to 0.0098 in), but can range up to 0.005 to 0.01 mil (0.00013 to 0.00025 mm). Buying 1 inch hardchrome bar stock means that there is no need to ream or hone more of the bushes than you have to. Like all metals used in precision hydraulic applications, hard chromium plating is subject to different types of quality requirements depending on the application, for instance, the plating on hydraulic piston rods are tested for corrosion resistance with a salt spray test. As well, the metal plating varies according to the task you wish to put it to. Steel offers an immense range of possibilities. Hardchromes have hundreds of years of history and tested experience. If you go to any hydraulic application, (such as a earth moving machinery), you will see that the actuating levers are hardchromed. The immense feedback level and choices of bar quality make it an ideal kingpin. The eMog group spread its efficacity. I have had three Morgans, with an aggregate of 225,000 miles on them (and counting!). I have used the HC kingpins on them since 1997 and never needed to do the front end again after installing them on each car. In a nutshell, they eliminate the need to ever do a front end job twice, at least in your lifetime. I have run these hardchromes with bronze, DEVOL and Vescanite bushes.
PM and the Factory tried chroming pins in the 50's but simply plated them with Show chrome. But this was an error. Show chrome is very soft and if the pins are not centerless ground and this type of chroming actually makes the surface anomalies worse. The soft surface didn't last more than a couple of weeks of driving. So sadly, the chroming idea was shelved, but even worse, it became a given to them that all types of chroming would not work. In 2003, I was consulted by the Factory when they ran into trouble with mild steel pins and DEVOL bushes. We went back and forth for a couple of weeks and I tried to steer them to hardchromes, but was unsuccessful. They went with their current stainless steel. Stainless steel also comes in different grades, though there is a much more limited grade range and a shorter history for all of them.
Invariably, the hardchromes lengthens the lifetime of the front end by many multiples. Two aftermarket sources sprung up early on, one being Greg Solow of the Santa Cruz, CA "The Engine Room" who hardchromes Morgan kingpins (thickening them by approximately .012") and the other being Machiel Kalf from the Netherlands who uses pre-made 25mm hardchrome bar stock. As both are not exactly 1", the diameter of a Morgan kingpin, both must be installed WITH the bushes to ream/hone them to a proper fit. The advantage of 1 inch hardchromed bar stock is that the kingpins can be installed at any time, simply replacing the ones that are there without redoing the bushes etc. This will extend the remaining lifetime of the existing front end without further ado. Though the ideal is to change the bushes as well at the same time, there is no harm in adding many years onto what you have with limited work.The reluctance of the MMC to move to hardcrhomes is explained above. But the reluctance of the community stemmed from the prices at the time. In Greg Solow's case, the hardchroming of used pins ws very expensive. In the case, of Europe and the UK, the pins sold by Kalf and which he supplied to Melvyn Rutter were priced (350£) so much above cost that it discouraged the larger community on that side of the Atlantic from considering them. However, in 2001, with eMog encouragement, John Worrall of Heart of England Morgans began offering them at a normal markup and the price went down to 40£.
One can now purchase hardchrome from many sources (see Heart of England Morgans or Mulfab). It is not a complicated procedure. I make my own out of C1045 or C4140 bar stock at my local machine shop. Anyone with a lathe can do the job. It was much harder to convince owners to try them, even without the cost difference!
The reason hardchromes save the bushes is that the stock mild steel kingpins rust quickly at the bottom, especially if the car is not used daily. The rusted kingin surface acts like a rasp and eats away at any bushing materiel, whether bronze or (much faster) plastic. The hardchromes keep a slick, effectively self-lubricating, rustless surface. (Unpolished stainless pins are not as helpful.)
However, because of the experience with soft chrome 50 years earlier, (see above) the Factory moved to stainless steel pins in 2004. This is a non-typical use of stainless bars and, unlike the hardchrome bars, they have no history in this type of usage. To date (2008), there are many verified reported cases of premature KINGPIN wear with the Factory stainless kingpins, indicating they may have chosen too poor a grade of metal. The curious thing is that this wear occurs even with the plastic Devol bushes when the bushes show no wear!! It is hoped that the MMC will switch to hardchromes or upgrade the stainless bar stock they are buying
Hardchromed or stainless kingpins can be fitted to ALL classic Morgans.
N.B. Extensive experience with the hardchromes has shown that the life of the front end can be extended significantly regardless of what type of bush materiel is used or whether they have annular grooves, or lips to prevent grit entry, or gaiters, or garlic or ritual chanting.
The DEVOL MORGANS (2001-2006)
by Lorne Goldman (5 updates since 2001)
At the end of 2001, after a transition period of a few variations on the theme, the Works removed the one-shot oiler system first installed in the early 1950s and began using a new kingpin bush materiel rather than the traditional phosphor bronze bushes used for almost a century. Many have refer to them as plastic" or "neoprene" or "nylon" but, in fact, they are not. They are Factory machined from a polyethylene plastic called Devlon S made in Scotland by a company called Devol. They were brought in to extend the notoriously short Morgan bush life AND to make the task of bush installation easy rather than the involved task it is now. Sadly, a number of factors and teething problems intervened, giving these bushes an undeserved bad reputation. After approximately 2500 "Devol Morgans", the MMC abandoned the idea and returned to bronze bushes. Subsequently, the MMC stopped supplying Devols and the Devol cars must use oversize non-resultant fit bronze bushes, or make their own out of Devol material.
The primary cause of premature bush wear was never the bushes or the materiel used for them..it was the use of mild steel kingpins. These will quickly rust at the bottom bush when the car is stored for anything but a short time. The exterior surface of the kingpins quickly becomes as rough and acts like a rasp to grind through any materiel, especially the new space-age materiels. Many moggers, myself included, had avoided this by using hardchromed kingpins, a item made for hydraulic applications for the last century and more. 100,000+ mile front ends were acheived the 1980s.
In 2002, right after the first cars were fit with Devol, Bill Beck, a fine fellow and (the last) full mechanical designer at the Factory had left their employ. By the 2003, reports were coming in from everywhere that the bushes were lasting as little 3000 miles! A quick examination showed the cause. They looked for a solution.
I was contacted by the Factory by the director then in charge, Mark Aston. He wanted input on hardchromes. They had reasoned out that any surface that does not rust should solve the problem. We went back and forth for a month or so. Sadly, for reasons explained here, in early 2004, the Company moved from mild steel to stainless steel kingpins. This is an ususual materiel to use in this application and there was no track record for it. By 2006, some owners were discovering that the kingpins (insufficent quality) were wearing faster than the Devol! But by then Mark Aston had ceased working for the company as well.
One super feature of these bushes is that were made to be a "resultant fit" meaning that the bushes will automatically have the correct ID once pressed into the stub axles without the need for reaming or honing. They also can be removed and inserted with the need for a multi-ton hydraulic press. To makes this possible, the Factory reamed the stub axle tube to a standard ID. this was not done and the ID varied from stub axle to stub axle as their tubes distort when they are welded to the cast stub axle. We shall call these specially aligned axles the Devol cars. They were a massively smart move, multiplying Morgan front end longevity and making the dreaded front end jib something any owner could perform on his driveway. However, Morgan Morgan had problems as the bushes were not as simple to produce bushes made from the older bronze stock. The older bushes had no need for precision as they were individually fitted to each and every kingpin ON THE CAR. And, at the time the company did not own a modern honer to make the job easy and perfect. The front end of some cars would seize. Sadly, in 2006, after appromimately 2500 cars they abandonned DEVOL and the entire concept of a reultant fit in any material. They now do not make or supply Devol bushes, forcing the DEVOL cars to move to specially made over-sized bronze bushes which must be specified on order, then reamed and mated on installation. The 10 minute job at home is now hours with specialized equipment mentioned for other Morgans.Regular bronze bushes cannot be fit to DEVOL cars...they create a too-loose fit.
The Works reported that their original test car reached and passed 50,000 miles without discernible bush wear. The earlier bronze could be expected to last 10,000 to 25,000 miles depending on the quality of maintenance and kingpin type. In my case, my present Devols (now fitted with hrdchrome kingpins I made locally, have no discernible wear in 110,000 kilometers and counting. However, my first set of Devols, delivered with mild steel kingpins, were shredding after 3000 miles! The difference was usage. The Factory test cars are used constantly, which left no time for kingpin rust to occurs at the lower bush in over the times the vehicle is dormant for more than a few days.
These bushes have a tiny ridge on the ends. This ridge acts as a barrier to grit, and draws grease into the area between it and the grease reservoir in the tube (the space between the bushes and the kingpins). When reamed, this useful ridge is removed. However, after Bill Beck left, some of the cars began appearing with the bushes pressed in backwards with the little ridge inside the tube. This acts in the opposite way, allowing grit to accumulate between the bushes and the kingpins.
SWELLING & SEIZING
Most importantly, the Factory had an inconsistent experience with the Devol bushes in the UK. This was self-caused but they did not understand that at the time. By that time, Bill Beck, the former chief designer had also left the companny. The reaming of the stub axle tube, and the bushes, made by the factory from materiel supplied to them, were not made in a consistent size, id or od. As well, after Bill Beck left, the production department changed the amount they were reaming the stub axle tubes and that changed the resultant clearance. Some Devol cars began seizing the kingpins. ALL reports of seizures are from the UK. Elsewhere the bushes performed superbly if the kingpins were changed to something that doesn't rust and mileages of over 100,000 are heard of when they are combined with hardchromes. The ease of installation is a pleasure taking only minutes to swap bushes rather than hours of precise machining and specialzed equipment.
Devols were used for 5 years or approximately 2400 Morgans, or more than 1/2 the trads made in the first decade of the millennium. Because of their larger tube ID they must continue to use Devol or use oversize bronze bushes. The company will no longer supply Devols. Oversize bushes can be made at a local machine shop or purchased from Mulfab.
Nevertheless, it is manifestly apparent that this type of technology was/is sadly beyond the capablities of the Factory, especially asince the departure of Bill Beck. The Morgan Dealership network is, understandably at sea on the subject as well. Soemtimes, you look around, and realize that you are the only one left standing! :(
For all these reasons, I recommend the following to the Devol Car Owners whose front ends needs attention;
IF YOU ARE IN THE UK: Use hardchrome kingpins and the oversized bronze bushes for Devol Axles.
IF YOU ARE OUTSIDE THE UK: Use hardchrome kingpins and Devol bushes made for Devol Axles.
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