Hello,

I'm trying to get the kingpins out of the front axle on my 1929 RK saloon and one will not budge. I loosened the cotter pin, heated it with a big blowtorch and used a kingpin extractor courtesy of A7 Components. I thought I was getting somewhere when all of a sudden the extractor sheared off leaving the threaded portion in the top of the old kingpin. I think I can get the broken bit out of the kingpin with a screw extractor but then what? It doesn't look like i can get it out with a hammer and if a specifically designed extractor wont do the job? Can I cut it out?

If you remove the axle, turn it upside down and then remove brake cam and bush you can drive the king pin down with a suitable drift and large hammer. Support the axle properly near the stub axle, generous heat is often required.

A few weeks ago I changed the kingpins on a Ruby.
One side would not come out, and I struggled for a bit. Then I remembered. A common mod is to grind a flat on the pin and use a cotter pin rather than the half moon thing. Just try and see if the cotter pin knocks out.

I have seen this as well Alan - I believe that a quantity have been made like this in Australia.

Same as R suggests,

But What I find helps, is to drop the top of the stub through the vice jaws onto any solid part of the vice.

This way none of the impact from the drift is lost.

If you use an extractor on a seized kingpin, it like useing a flywheel puller.

You can tighten until something bends or brakes.

With the flywheel puller you can impact the end of the centre bolt you are tightening. Usually it will eventually go.

With the kingpin extractor, tighten. Then turn the axle upsidedown do as R suggests. Then impact the other end. Tighten extractor and repeat.

It's easier to show someone, than it is to explain.

Tony.

Location: Huncote on the pig

Much obliged to everyone for the advice

Photos

Not much progress. I can't use the kingpin extractor, I wasn't able to get the broken bit fully out of the end of the kingpin. I have a 1/2" steel drift. I haven't removed the cotter, I have tapped it a couple of times and it seems to be tight in the hole so I'm assuming it's the half moon variety. I have heated the stub axle so hot it smokes. I noticed the hole in the bottom is smaller than the hole in the top and that you can see the bushes in the top but not the bottom. I have been trying to drift the king pin out upwards, i.e. from the end with the brake cam bush (removed) and it hasn't budged more than about 1/4" I tried pressing with a 2 ton press and all that did was bend the drift. The end of the drift has peened into a mushroom shape. I'm worried I'm doing something wrong. Is it tapered? is upwards the right direction? How brutal should I be with the cotter? Should I just persevere with the lump hammer?

Has it really moved, even 1/4 inch?

Because if it has moved, it will come out.

You need belief, and patience.

Hit it back the other way, turn over, hit it back.

Repeat, with heat, and lubrication.

For an hour or two, as required.


If it moves, the cotter isn't doing anything. But I would drill most of it out, working from both sides, anyway, so I could get a bit more lubrication into the middle.

Good luck.

Simon

Location: On a hill in Wiltshire

Hello Alan, generally speaking the half moon cotter will show slight movement as you tap it from one side and then the other ( unless it is rusted solid). This slight movement is possible because most half moon cotters have stretched a little.
You say it has moved a quarter of an inch and then stopped, so it could have been modified wit a flat ground into the king pin and a normal bicycle taper cotter fitted. Heat the cotter and have another go at hitting it right out.
Had this problem on a 23 axle a few weeks ago, they were normal cotters but the pins were solid, on the plus side once you get them out the axle eyes will probably be in perfect condition as mine were. An axle with good eyes is hens teeth so persevere. Cheers Ian M

Location: Bristol

Victory!!!!!!!!!

https://goo.gl/photos/SDifYaQr7jSVZwdZ7

I must say my language wasn't all that ....gentlemanly....when the king pin finally came out.

Many thanks to everyone who contributed advice

Now on to the next problem

Alan,
What a relief,was there an obvious reason why it played so hard to get?
J

Location: As far east in Kent as you can get

They were the wedge-shaped cotters not the half moon ones. Once I had removed the cotters the king pins were still and absolute fiend to get out, mind you.