The Roller Bearing Conversion (The whys and wherefors)
by Lorne Goldman, John Sheally II, Peter Mulberry & Bill Button June 2005 updated May 2020 updated, May 2022 updated

1. The Whys

2. John H. Sheally II/eMog Pub Version

3. Mulfab Version & Their Fitting Instructions

4. The Morgan Motor Company Version & Caution

5. Wolf Performance Version (my current favourite)

6. Watchpoint for Post-2008 MMC System

7. Watchpoint2 for Earlier Morgans

8. Watchpoint For All Morgans (read first)

9. When All Else Fails

THE WHYS
by LORNE  GOLDMAN

As the stub axles move up the kingpin when the car goes over a bump, the large kingpin springs compress (obviously) and produce a twisting motion (not so obviously). All other things being equal, this twisting motion would be relayed to the spindle and would result in a slight turning of the wheel. When this occurs and a certain speed, it sets up a harmonic bounce which can express itself in a violent shimmy.

To avoid this, HFS Morgan placed a bronze plate between the spring and where its sits on the spindle. The bronze plate then is held steady (and untwisting) by being bolted to the damper blade which, in turn, is held at the frame. With all this, the spring's motion is now transferred to the immobilized bronze plate rather than the spindle. Of course, since the spindle moves up and down the damper blade cannot be bolted to the frame as it must move in and out to follow to the spindle's movement up and down. Ergo the blades are "sandwiched" into a slot made of small metal plates and the damper blade shims.

This system has worked for almost 3/4 of a century. Its drawbacks are the maintenance it requires (as the blades get loose they allowing twisting to occur at the spindle unless the shims are readjusted and the blades and shims deteriorate. It handles the twisting movement in a less efficiently manner than other solutions. The roller bearings are one of these "other solutions" and a good one.

RESISTANCE

With the standard Morgan setup, the twisting action of the spring is the twisting action of the spring is dissipated on the bronze plate (attached to the damper blade). As the bronze plate is, in effect, fixed, there is some resultant resistance to the twisting on the plate.

In the roller bearing system, the twisting is on the collar and washer which are seated on the bearings and turn on these..ergo no resistance and lighter steering.

CLEANING

As the bearings are closed to the elements by the washers under them and the other washer atop them (with the collar and spring pressure to hold it all sandwiched, there is nothing that can get in and dirty those bearings. (Second) ergo, though the area would require normally cleaning, it would be not susceptible to road dust as it is fully enclosed in the stainless washers and I would find it hard to see how wear would be a factor.

I have attached a diagram the reflects my understanding. A 4-story sandwich. After removing the kingpin assembly and stub axles, the bronze plate that attaches to the damper blade is removed from its position around the stub axle tube (where the kingpins are placed). A washer is placed on then the thrust roller bearing is pressed fit. Another washer  is placed loose on the bearing ..diagram "C", then the top hat cover is placed on top of the assembly. The kingpin is re-installed and the large kingpin spring fits down over the kingpin and sits on the top hat. The top hat is used to properly position the spring and the sandwich and keep the grease in the bearing assembly and debris out. The top hat must turn freely. If it is too tight, use some sandpaper on the inner edge until it slides loosely.
 
JOHN H. SHEALLY II & the eMOG PUB & GRILLE  Here is the "Sheally Setup". It is quite simple. The views included are of it on John's new Plus 8 Morgan Racer. If you look close under the bottom of the red main spring you will just see the stainless washers sandwich with bearing in between.

What you can not see is the machined collar pressed over the kingpin tube to center the bearing and washers. The collar or collet is drilled to match the grease fitting hole so that the existing fitting can be used to grease the bearing from inside to outside serving also to clean  it each time it is greased via gun.

The bearing is a FEDERAL MOGUL/NTA 2840 and the stainless washers are FEDERAL MOGUL/ TRA 2840 (total of approximately $30US collars extra). Toss the damper blades and bronze thrust plate and enjoy quick smooth steering at a small cost with my applied "KISS PRINCIPAL" I have found that the setup is too simple for a lot of folks to comprehend.

You have to make your own from round steel stock or good quality steel pipe. It is very simple, you are making a steel "ring" to press fit over your spindle bushing tube. make the ID tight to press fit over the tube and press fit all the way down to where your bronze plate would sit. make the OD to be a snug fit to the ID of your thrust roller bearing. put the stainless washer over the tube and slide down over the ring "collar" followed by the bearing and the second washer (lube the bearing well on both sides) and make sure your grease will feed to the bearing from your existing (grease nipple/zerk) by drilling a small hole in the ring and line it up with the oil hole on the spindle. Place your main spring in place and assemble spindle and kingpin, etc. and enjoy your Morgan. Sincerely, John H. Sheally II


top hat right side up
Kits of the Sheally set up were machined and assembled through the efforts of Roger Shawyer. Roger had the collar produced and used a grease ring to spread the grease evenly about the bearing. Care should taken to ensure that the collar freely turns about the tube. These assemblies, made as an eMog Pub initiative, are no longer available. However, they can be reproduced by a machine shop to order along with the other parts are listed above.. 

top hat upside down

PETER MULBERRY

Peter Mulberry extends the thrust roller bearing principle ..using different ball bearings within a housing as can be seen by the picture. As well, the main spring is changed. For racers, there is an interesting adaptation (shown in the picture) of a treaded collar at the top with an adjuster. This allows the ride height to be changed quickly and conveniently.

Peter adds a worthwhile note on the reasons for vibration AFTER this mod.

"Probably the most likely cause of wheel wobble when fitting roller bearings is removing the damper blade. Strange to believe but every Morgan is different, some will 'wobble', some not at all.  Why could that be? What use is fitting rollers when the Mog is going to shake her head along the road?

The advantages have been commented several times, lighter steering, smoother action, disadvantages as far as I believe are capital outlay to buy the bits and getting your hands dirty to fit said parts. So this still does not answer the problem of wheel wobble. So why take away the damper blade?

Trying not to get too technical, the blade fulfills two functions. Without the bronze thrust pad the road spring would sit directly upon the stub axle. When the steering was turned the spring would turn as well, but the top of the spring is hard against the top of the crosshead which does not want to turn so the end result is akin to winding up a large spring in one direction and unwinding in the other. Very strange. So we have the bronze thrust pad between the spring and stub axle which stops the spring winding up. The second function is a friction damper to give it its correct name. Two key words here, first was friction, hard work and effort,  roller bearings take all that away, second word was damper. It is damping the oscillation that is wheel wobble.

If you still have the dreaded wheel wobble after the bearing installation, look to your castor angle.  A few will be conversant with the term, but basically it is the angle that the kingpin leans backward as you look at your car from the side. It is what gives your steering its self-centering effect. Too little and no self-center, too much and grossly heavy steering.

Everybody must have pushed a shopping cart sometime. Ever had one that the wheels do their own war dance?  The factory measurement for castor is 4 degrees, give or take a bit for allowance. If yours is a bit less you have lost the self-centering ability and gained wheel wobble, if you have a bit more than 4 degrees you have one of those delightful drivers that track straight and true with hands off the wheel. I always set mine up at six degrees and have no problems at all. Unfortunately the factory have made it all non adjustable. But it can be tweaked if you know what to do. If you are not sure where yours is visit an auto align center and they will give you a read out of your front suspension. Then you know. I use these..two Morgans, 170,000 miles, no problems in 18 years.

WATCHPOINT2 FOR EARLIER CARS (2022): Pity, somehow this important note got lost during one of its updates. Within the eMog community, many (100s) performed this modification. Overwhelmingly, they were successful and without issue. However, we also found that earlier cars became susceptible to the dreaded Malvern Dance, a wobble in the front end. The thinner tyres and less castor (the modern era began with 4 degrees) were vulnerable than later cars. One of the best home Morgan mechanics we had, the well-respected Bob Nogueira, found this to be the case with his 1960s Plus 4.

He unassembled the front end and re-installed the damper blades with the bearing system. though this may seem odd it isn't. Damper Blades are a better method for divorcing the inflences of the road from the main spring while steering bearing/races easy sterring of course. The comnbination causes no harm whatsoever and damper blades do not add sufficient height to pre-load (aka stiffen) the main springs as the Mulberry and Factory bearing/races might do. (I installed shortened Main Springs with my Mulberry System, they can be had from Mufab at the same spring rate mor any other you might want to try.)

Sadly, there newer English-speaking forums are not very experienced or knowledgeable with 4-wheelers and their format does not encourage reliable results.

THE MORGAN MOTOR COMPANY (PostScript in 2009) (another in 2020)

The bearing systems do make the cars much easier to steer but also more likely to vibrate and wobble if all is not as it should be. When anomalies (ie.vibration) were experienced with older Morgans (pre-1968) we were forced to examine more closely and found and corrected other problems, after which all was well. 

If wobble/vibration is experienced by later cars (post 1980), it normally indicates a damaged, very poorly set up or poorly maintained front end which should be brought to the attention of your mechanic. In such cases, if this seems too much of a hassle, you can rebuild your front again with the damper blades, with or without the bearings. We do not recommend you increasing your castor without resort to an expert who has done so before. When all else fails you can try the Mercedes damper.

After this article was posted, the Morgan Motor Company copied the system designed by Peter Mulberry. Like the Mulberry system, the height of the bearing assembly requires the use of shorter main springs. (Be careful which spring rate you get!). After a period without, the Company began using drilled kingpins with grease nipples. This is NOT the one shot oiler system that was happily removed some years ago. The new passage is not for oil, but rather made larger for grease and is drilled further down to feed the steering bearing assembly which, unlike the other systems described above, it seems the Factory did not pre-pack their assemblies with grease on installation.

WATCHPOINT FOR POST 2008 CARS From the eMog Pub in January 2004 and updated January 2011 and in June 2020.

All these bearing assemblies NEED grease. This was provided, in pre-2008 cars with retrofits, by the little grease exit hole the MMC used to drill at the junction of the stub axle shelf and the stub axle tube. (see image)  For these bearing assemblies, this exit was perfect as it comes up under the housing at a place where it flows easily into the whole assembly and the bearings. After a short delay, the MMC drilled three holes in the stub axle tube to feed their bearing assemblies.  However, ever more frequently, when owners DO open up this area, it is found that the MMC bearing assemblies are bereft of grease, dry, with signs of rust and often seized. This results in the opposite effect that these systems are supposed to address. Rather than easing steering, these bearings make steering harder and can have other sad expressions...they must be addressed. Why did this happen. A number of our favourite gurus have added their speculations to my own below. Any of these or a combination of them could be causing the problem.

1. It seems the Factory does not  pre-pack their assemblies with grease on installation. It has long been thought that with an exclosed system, pressured closed by the immense force of the compressed mainspring, that once packed, these bearing assemblies would NEVER lose any grease. That has been the case when I have had the occasion to disassemble my Mulfab front end. 

2. On disassembly, we have discovered that the seal the MMC uses, has a hole in it.

3. Owners are, as a rule, pretty timid front end greasers. Improper greasing is rampant, even among those who are concientous about it. The grease gun becomes dislodged, or they give up far too prematurely rather than waiting until they see the grease coming out the right place.

 Any of these things might be causing the evidence we are seeing..but regardless of the cause, IT MUST BE ADDRESSED.

WOLF PERFORMANCE  June 2020

Wolf Performance (aka Cain Poulton) is a relatively new entry into steering bearings sweepstakes. Cain has come up with two versions, one based on roller bearings and the other on thrust bearings. Frankly, both have advantages..it is a matter of which of their charcteristics you favour. No complaints or feedback has yet to be heard.

I am always pleased to see new and honest suppliers enter the Morgan community. Too many old stalwarts have retired or moved on to other things since the Company began purloining their ideas outright rather than encouraging their ingenuity as Peter Morgan did for decades. :( As well, in the last 15 years there has been much super expensive silliness promoted, discouraging owner learning and ideas as well, prejudicing the cars and culminating in the lack of real development of the trad for the last two decades, a factor in its recent demise. 

I am now giving THESE bearings my highest recommendation for this genre of components. It is not merely their price, it is the quality of their manufacture and design. As well, with their lower height, they can be swapped in without requiring shortened main springs.

Spring Length Watchpoint: In each of these cases, when retro-fitting thse bearings, one compresses the springs by the height of the height of the top hat cover of the bearing. The amount of this compression varies from system to system, negligibly with the Sheally method above and the most with the Mulberry system, which is undoubtely thes strongest and the most widely used before the MMC copied the system into its stock cars. The other systems compress the springs somewhere between Shally and Mulberry methods. Proper Plus 8 springs have 140s or 140lbs per inch but these were changed to a lower rate (along with the Morgan Plus 4s and Roadsters) which is why they feel "wallowly" to old timers.and steering precision appreciaters. Dealers, racers and agressive drivers in-the-know swap them out on arrival.
And rebound springs and the rebound section here in section 8, are already too long, and all have spring rates double that of the Main Springs. That means that the top hat flange compresses the springs and extra, for example,1/2 Inch or adds another 60 pounds of pressure if the same length spinrgs are used. Along with the rebound problem from the Factory, this will prejudice handling and comfort even more. Astute installers will notice that they must compress the Main Spring more to re-install the stub axle..or that the bolt on top must be longer. What they are doing is making their front end stiffer when their goal was to make their steering easier.
Sadly, some of the suppliers who copied Peter Mulberry, mention nothing to their buyers. Peter Mulberry used to receommnded buying the same Main Springs but shorter ones or to cut the existing main springs down. That is what I did for all my Morgans.

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