Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Kingpins - DaveW's How To...........

The time has finally arrived. Another wet but warm Saturday.
I started at 11.30 and finished at 4.30, so five hours on this stint.

Before I start - this job is SAFETY CRITICAL.
You should not attempt this job unless you are experienced in dealing with suspension & brakes. It is not suitable for a first foray into DIY mechanicing, so if you are not experienced, let somebody do it who is.

First, using Uncle Phils tool.......loosen the wheel nut.


Next jack up and place securely on axle stands. Here there are two under the lower cross tube, and two under the gearbox cross-member.


Next remove the wheel.


I found some casting marks on the gearbox, so here they are for reference......... They are on the nearside bellhousing.


This is the rear of the nearside brake caliper. Access to the top bolt is very tight. The Caliper bolts are 3/4AF.


Here is the socket in place - it fits easier than I expected.


With the two bolts removed, the caliper can be hung out of the way using cable ties.


The split pin which retains the hub nut can be removed through a hole in the splines. I marked the nur with tippex, so that I can refit in the same position, the nut was finger tight. It's important to note how slack the hub bearings are before loosening. The nut is "one and 3/16" inches.


Once the split pin & nut are removed, a rubber mallet can be used to remove the hub.


A bit blurry, but this shows that the washer which fits under the nut is punched so that it can't rotate.


More to follow>>>>>>>>>>

Next the damper. Top nut is 9/16 Nyloc.


Once the nut is cracked it's necessary to use a 4mm Allen key & ring spanner.......


Lower nut is 9/16 Nyloc. Access is a bit tight.


It's important to protect the stub, so plenty of masking tape.


While access is clear, here are a couple of shots of the undertray...........




Next the track rod end. Another 9/16 AF Nyloc.


Once the nut is loose, use a splitter.......
Leave the hut on the end to protect the threads.


Next loosen, but don't remove the top bolt.


More to follow>>>>>>>

Here is a picture of the spring comperessors I bought for the job. It turns out that they are only just up to the job. The Mog springs are a bit of a challenge for Motorbike compressors......



A bit messy. but compressors ride round the spring, so I tried to keep them in place with cable ties.


Incidentally, the stub was quite tight on the kingpin.

I removed the damper blade at the thrust plate end. Two 7/16AF nuts & bolts. It simply pulls out of the chassis fixing. I haven't decided how to tidy the chassis end up yet, as with swivel bearings, there will be no damper blades.


This is the kingpin bottom nyloc. It's 3/4"AF. I took this off, but replaced it loosely as it retains the rebound spring tension so is best left in place until the tension is released.


The idea here is to progressively loosen each nut & bolt, and replace with longer bolts until all the tension has gone. I replaced the centre nut after I'd taken this photo. The nut & bolt on the left is removed pending the fitting of a longer bolt in order to continue. These are 1/2"AF. The one on the right is blocked by the reaction bar which must be either loosened off or removed.


Three nuts & bolts hold the bar at the chassis end.


Extended nuts & bolts in place I hadn't replaced the centre nut at this stage.


The only tension left now is the rebound spring, and when that nut was removed it still has a kick. I should have continued with longer bolts each side, but no harm done, except the rebound spring rolled down the carpet tiles and left a greasy trail!!!!!



More to follow>>>>>>>>>>>>>

So, once the top bolt was taken out, the stub axle and spring assembly lifted out sideways and upwards. I'd expected to have to lower the kingpin from below. but that wasn't necessary.
This job is incredibly messy, and I'm running short of old sheets, and must have used more than half a dozen pairs of white gloves so far. Here's how it looked.......


And here's what's left in place......


Disassembled - top left is the bump rubber, visible in the spring is the tube protector which covers the upper kingpin.


The kingpin is stainless steel, and here you can see the scuffs and wear at the bottom end. That has happened over a very low mileage.


Here is a selection box of all the bits taken off!!!


Here's the original spring. Apologies for the quality, I couldn't get a focus.......
The writing says Eibach Federn 05/05 Morgan Plus 8.


I took the opportunity to spray some rust protector down inside both cross tubes.


More to follow>>>>>>>>>>>>>>>>

I had devised several schemes to remove the bushes. Some say, use a hacksaw down the tube to cut a long slot, which weakens the bush so that it may be drifted out. Some say use a cut down washer which will fit down inside the bush, then turned and used with a nut and threaded extractor. There are probably other ways.
It occurred to me that a socket on the end of a long extension might work. I jammed the stub axle between two timbers over the pit, becasue my vice is nowhere big enough!!!!!
So the chosen socket was just small enough to slide down the inside of one bush, and then was angled against the inside end of the other. Many hard hits with a hammer, and.........
I'm prepared to sacrifice the socket extension - it's old.


The second bush is easier, because with the first bush out of the way, a larger socket can be used which has a better location on the second bush. They are still very tricky to shift.
Here's a cleaned up stub, with accessories.


I used an old tea towel (Shhhhh!) to clean out the old grease......


Then after a degrease, a blow over of primer......


Followed by a coat of satin black.


Note that the threaded shaft for the damper is available as a stainless part, but I have discovered that my new stainless shafts have the incorrect thread for these stub axles. The originals are a finer thread, so be careful. Cross threading the stub axle will be expensive.

Finally, a lick of paint on the reaction bar........


So that brings an end to my first stint, and five hours work, without rushing too much. The problem with kingpins is that once you've done one, you must repeat the whole thing. Although the second pass is usually quicker because all the right tools are out and the technique should be better!!!!
PS - All the fasteners so far have been AF. EXCEPT - the damper shaft on the stub axle is 7/16" Whitworth.

Wonderful post Dave, superb photography, clear labeling, no stone left unturned. I have no intention of dismantling my own steering but it is a joy to see yours, warts and all, laid out in technicolour.
I have never seen a King Pin before and it was worth the wait.
Was there some play at the wheels that got you changing them.

Dave

I had some play in the nearside lower bush Dave, so I intended to change to hard chrome pins, and that gave me the reason. It wasn't MOT fail play, but any excuse eh?

What's strange is that you would expect the lower grease nipple to have a channel into the lower bush. That's how the MGB and Midget is designed, and it can be tricky lining up the hole in the bush with the hole in the stub so the grease gets through. But this is designed so that the lower nipple comes through just above the bush. Now that's fine with an oiler, because the oil will run down into the bush. But with grease, the grease will sit on top of the bush and only the upward movement of the stub axle will wipe the grease into the bush. And excessive greasing will do nothing more than fill the cavity between the upper & lower bush with grease, but there are no wearing surfaces between the bushes. Therefore I may do a first shot of oil when it's back together, and I'll also be pre-greasing the bushes thoroughly. I've had the bushes sitting in an oil bath for the last six months by the way!!
In respect of the upper bush - the new kingpins have a tiny gallery which runs from the top bolt/grease nipple, which exits a narrow groove adjacent to the upper bush. This will easily get blocked, so again I'm wondering about using oil - but not Hypoy due to the additives which attack yellow metal. I'll post a picture showing this in the second phase.
The original stainless kingpin though, which had a top grease nipple, doesn't have a visible gallery and I'm wondering if its blind, and of no use.............

we are indebted to you Dave for your superb essays into Mog maintenance, surely now MMC have employed the services of a talented designer - and reaped the benefits -they could look to doing the same for the chassis and putting to bed once and for all the Legend of the King-Pins, they must have amassed enough data over the last 100 years to produce a definitive solution to the manufacture/maintenance/lubrication[freqency and medium] of this pillar of the establishment

Superb..I think the only missing information that I would find useful is the recommended lengths (and thread dia.) of the bolts used to take off the tension of the bottom rebound spring. (If you felt the ones you used were too short)

Also where did you get the Chrome Kingpins from and what is the reasoning for soaking the bushes for so long?

And...what did you use to paint the stub axle and other parts (Black).

Sorry to ask the above but just want all the details before I go into battle as well!

Keith/Easter

Thanks - glad to be of assistance.

I'll be using threaded rod to refit the stub, so I'll document the sizes when I do that. It will be M8 but I won't know what length until I start. I might attempt it without the spring compressors. We'll see!!
I've just got some threaded rod from Wickes today in three sizes - because I'm making a tool to refit the bushes. Well, I'm cobbling something together actually. I'll probably use M10, but also got some M12 just in case. I have an old Cortina bush extractor which I used on the MGB, which will be a major part of this tool.
The hard chrome pins came from Heart of England Morgans. I also got most of the bits from there, but the ball bearing swivels and shorter springs are from Mulfab.
I soaked the bushes to allow some oil to penetrate. It probably doesn't need that long, but I bought them in good time. It's just 20/50 engine oil, nothing special. The kingpins have also been immersed, but it's probably wishful thinking, although at the molecular level who knows. Chrome plating is porous after all!!
Colin M. mentioned that oiled bushes can turn in the stub when reamed, so I used some degreaser on the outsides as a precaution, and they are now in the freezer - easier to fit if cold.

The paint is just aerosol satin black - I'll post a picture when I restart. By the look of it, that will be next Saturday. If the pressing and reaming goes well, side 1 might get finished on Saturday.