Morgan Technical and Other Topics Blog: Dave Wellings on Fitting New Kinkpins

Dave Wellings on Fitting New King Pins

Today I made a start on Mr Bumble's kingpins. First here's all the stuff on the bench.

I used some thick leather, doubled over as a buffer and the spinners came off much easier than the old earless spinners.

Here's my lifting beam under the cross tube and held by axle stands.

This next photo is quite important.

The Caparo calipers don't use split pins, they have dumb bell like retainers which can be drifted out either way, but are held in place by "traditional" spring clips. I managed to damage one of the spring clips when removing, but have some new MGB clips in stock.

However, although they look the same, the MGB items are very slightly narrower,so not really suitable as this would allow the pins to move slightly sideways. They would do as a short term fix. I rang BHM, but they don't carry the clips in stock, and have not supplied any. They don't come with new pads by the way. So I rang Rutters, but got the same response.

So I've contacted Caparo direct, but am not hopeful as these parts are pence in value even though they are safety critical. I'm presently looking into an alternative source so will let you know what turns up.

The other important thing to note is that the pads have a lip on the outside edge caused by the pads slightly overlapping the outer edge of the disc. I've filed the lip away, but it will recur as the pad and disc don't exactly align!

These pads are exactly the same as on my Roadster which has the earlier Lockheed calipers.

I hung the caliper out of the way on a cable tie, after checking that none of the pistons were sticking.

Note that the flexihose is armoured, but also has a clear plastic cover. The plastic cover has been worn through in one place, which looks like it may have rubbed on the tyre or rim.

So check yours...... This has not damaged the armoured braiding. When I fitted the brake reaction bars, I added a rubber hose buffer because the hose does touch the reaction bars. Note also that the caliper has two bleed screws.

Here's the split pin, just emerging at "two thirty" - o'clock. Needle nosed pliers are essential. The nut was finger tight, which is usual.

Here's the bare stub. The nut visible at 9 o'clock is the sensor I've spoken about before.

A cable runs from the back of this, into the loom at a multi plug under the wing.
Note the end of the rack. The boot is only held on by a cable tie, so it's very easy to pop the boot off and check the state of the lubrication.

Pack a bit of grease in the end if it's dry. If you put it on 'right lock', the rack will take the grease inside when you straighten up.

The S shape cable (below) is the sensor cable, which is threaded into the backplate and secured by the nut in the earlier photo.

This is the back of the disc (with fresh paint). Note the evenly spaced bolts and nuts. I believe these are to trigger the sensor, and I wonder if there will be this many on the other side.

And here we are with track rod end off, lower reaction bar removed, and lowering rods fitted ready.

I've also cracked the top lube bolt, and bottom kingpin nut. Note that this stub axle is very sticky on turning and is grabbing the main spring, even though it has MMC steering bearings.

When I get the stub off I will post pictures of the MMC bearing next to the Mulfab bearing.

I've been cleaning up as I've gone along, but be in no doubt that this job is incredibly messy. Grease everywhere......

Anyway, after a leisurely day, time for a break.

The next photo shows the difference between the MGB and Morgan retaining springs. I've had a response from Caparo, so will let you know the details as soon as I know more.

So - using the wind down method... this is how it ends up with tension off the main spring.

Then once you've removed the bottom plate, it lifts out.......

Here's a comparison between my original blue Roadster springs (marked "Plus 8"), and the Plus 4 springs - shorter to accommodate MMC steering bearings.

And interestingly, here are the rebound springs - the longer thinner ones are Roadster (05), and the shorter thicker springs are Plus 4. The coils are compressed at one end.

Next a comparison between the Mulfab bearings, which I will use to replace the original MMC bearings, and the MMC bearing which I've removed. MMC bearing on the left. The race is smaller than the mulfab race, and the MMC cover is rubber.

As removed there was significant stiction in this bearing, which is why the steering was not as light as the Roadster, already modified with Mulfab bearings. The Mulfab cover is metal, and it turns much easier.

Here's the top of the kingpin. As you would expect, it's as new, at 1" 'exactly'.

Here's the bottom. Admittedly not as bad as I expected:

But with a noticeable zig zag wear pattern with significant troughs:

There's also a witness mark where the bearing has been rubbing on the stub axle:

Now it gets interesting. Extracting the first bush is a test unless you use a press to push them both out the same way.

This time I thought I'd try sawing down the length, so made up a special hacksaw from two strips of aluminium with a limited depth.

This worked well enough, but that first bush still put up a fight.

For the second bush I used Mulfab's tool, and it came out easily........

And so to fitting the new bushes..................

For this I use threaded rod and bits & pieces collected over the years, plus suitably sized sockets to keep it all lined up.

Today the bushes went in easily................This is the lower bush with a socket over the top to help it align.

Here it is nearly home. The bush hanging out is an MGB anti roll bar bush which is a perfect size for centralising the threaded rod.

And here's the upper bush going in:

Reaming was straighforward. This photo shows the end of the pilot. It's only just long enough, and I've modified the end to provide a bit better fit in the hole.

I suppose that techically it would be better done vertically!

And here's the business end. It's an adjustable reamer so I go in on a loose fit first, then progressively go larger, testing the fit after each pass - going in from each end.

I also use cutting lube and the reamer makes easy work of it with just light pressure to make it progress.

Until suddenly the pin fits! How tight is a bit subjective, but this is reasonably tight - it takes a bit of effort to pull it back out by rotation.

Note that it should fall through under its own weight or hold with some grease added.

Then it's important to clean up inside - I sluiced it with plenty of WD40:
First pass:

Second pass:

And then a bit more cleaning out followed.

Before degreasing, etch priming and painting. It's been a busy day, but it all went well.

No more spare time now until the weekend.

I'll repeat this from the other thread - Brake Component Part Numbers: A bit more information now:

Caparo spring & pin part number: HCK215

Morgan "genuine parts" number for spring clips MBS 0675 (Thanks Richard)

Now here's the best bit. Spring clips are available from Rimmer Bros:
QP2740 is 1 spring clip - Rover SD1 - 2 piston caliper. �1.60 each (incl VAT) and you need four.

Or STC8574P, which is Retaining kit, rear brake pads (aftermarket). Includes 4 clips and 4 split pins (you don't need the split pins). �3.90 incl VAT
So the set is cheaper than buying four clips separately.

The special retaining pins are Caparo only so it looks like that will be a factory order unless you replace with bolts.

Yesterday and today I continued - first assembling the offside and the moving on to the nearside. I've decided to replace the pads with Greenstuff, which I'm happy with on the Roadster.

So - first I greased up the Mulfab bearing. It slots over the top and is a perfect fit.

Next the dust cover and bump stop was assembled and slotted over the top of the spring.

I used the dust covers from the Roadster - I replaced them with new ones when I did the kingpins, then cleaned & repainted the old ones for the next job. The bump stop is a simple length of rubber hose which is a tight fit in the top of the dust cover.

Next I sprayed rust inhibiting wax into the cross tubes:

Note here the flimsier looking lower mount which was modified to accommodate the adjustable camber plates.

I also dribble a small amount of oil into the track rod end.
At this point it's coming on nicely and is ready for the disc.

All nuts and bolts are checked twice. It's very easy when you are familiar with a job to forget something important!

And here we are back together apart from the pads........

More to follow.......

There are different ways of pulling the stub axle into position. Using a long top bolt is a very good way, but I've settled on my two threaded rod method.

It doesn't need spring compressors and the only tricky part is locating the lower nut on the kingpin - because I prefer to get the top lube bolt started early.

The only thing to watch is when the top of the stub meets the dust cover on the way up. It may need a bit of persuasion to slot inside, but on this occasion it went in easily.

So today I started on the nearside:
First those pesky pad retaining clips......I found a suitable sized drift, but because the pads had pushed out slightly the pins were stiff to get out.

Here you can see the lips over the edge of the disc:

I thought I could get away with retracting the pads without taking some fluid out of the M/Cyl.

But Bumble peed on the floor! Or rather on the rubber mat........

Ready for lowering:

Here's the disc and you can see that it doesn't have the extra bolts on this side because there is no sensor on this side.

The kingpin was worse on this side than the other:

Again, the first bush was a challenge to get out, even though I hacksawed four slots in it this time, but not quite far enough!

But the Mulfab tool made short work of the second bush.

Then the new bushes went in easily. First the lower:

Then the upper:

This photo shows how the lower valance and tray seals off the front of the car from road dirt:

And finally, I painted the stub axle, ready for reaming tomorrow.

Well, the first observation is that the new pads when fully located still overhang the outer edge.

The inner edge is bang up agaist the inner edge of the disc, so skimming a bit off each angled corner of the backplate, to 'edge it' down won't really work, although I did consider it.

I've had Greenstuff discs & pads on the Roadster for six years, they were fitted when I got it, and have been no trouble. Maybe I don't brake hard enough.

Anyway back to the story:

Here's a closer photo of the reamer. The silver tube on the right is the pilot with a sliding adjustable collar, which to be honest is not much use with Morgan stubs due to the length, but the pilot is essential to keep it straight.

As the cutting blades adjust right to left they ride up a taper so cut a larger diameter hole, They are retained at each end by a taper threaded collar. Black on the left, silver on the right.

This show the model number - there are loads to chose from.

Reamer adjusted, job done, and cleaned out - I'm getting faster each time I do this.

Here's the nearside on the way up. I slot a screwdriver in the base just in case the rebound spring makes a bid for freedom, but it seems quite stable and once it gets inside the lower tube bracket it can't go far.

Almost back together:

Pads and lube - it's just like Coppaslip.

Not enough angle to see the overhang...........just visible as a pink band.

So all I have to do now is make up a set of deluxe gaiters as I fitted to the Roadster after the kingpin job, oh and then do a full service. Good job I'm part time retired, and that MrsW is tolerant.

Here are the better pictures of the calipers & pads:

This one shows that the inside edge is right up against the wear ridge.

And this is the outer edge. It doesn't fit well......

Next time I'm in there I will chamfer the edges a bit.

So now onto the final stage of this job, previously done on my Roadster a few years ago.

First the leather inner gaiters. Cut from fairly thin leather, and with hand stitched velcro, 10mm wide.

Then treated with Nikwax. This is to resist water from the outside, and protect from grease on the inside.