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MG Midget and Sprite Technical - Suspension and Kingpin Bushs removal

After 44 years service my coil spings are being replaced as one is 24.5cm the other 25.5cm. As part of that I'm also replacing the drivers side wishbone and kingpin. I've taken the kingpin out the stub assembly but i cant get it off the wishbone as I cant turn the fulfrum pin at all.

The Kingpin bushes are still stuck inside the stub assembly and I cant get these out, any tips? Can I just stick an old screwdriver in and knock it out?
It looks like on the top bush had some wear. There is still grease in there but also other bits, again is this normal?

Thanks


Bruce Burrowes

Attached is a picture if the KingPin, is what I'm looking at normal in terms of wear?

Appreciate its hard to tell but this is the first time I'm doing this so I'm not sure what it should look like.

Bruce Burrowes

I wouldn't try and drive them out as they're a heavy fit normally, better to get some 1/2" or 12mm threaded rod and washers and find some sockets slightly smaller than the bushes to put against the bushes to push them inwards into the tube sleave area or pull them outwards into another socket larger than the bush OD.
David Billington

Bruce
As David sugests is the better way, but if you want to remove it by collapsing it, if you have a look at your pic. the bush isn't full circle ,it has a join through, shown on the left side in your pic. -If you are going to collapse it,do it just down one side of the joint and it will fold in easily--
Bit hard to tell on kingpin wear from a pic. but if it polishes up without any evident wear 'steps' in it it should be ok
The new bushes will probably need reaming to size anyway,so you can allow for a little wear
willy
William Revit

You may find that new bushes are not required. Try the new kingpin in the a stub axle and see it there is any movement.

if you do need to replace the bushes then they will need to be reamed out afterwards. There is a special stepped reamer for this but it can be done with adjustable ones. if you don't have access to these then perhaps buy an exchange unit from one of the usual suspects.
Bob Beaumont

Hi Bruce,
You say you cannot turn the fulcrum pin at all. They can be very tight or impossible to remove. I was home you have found and knocked out the cotter pin?
You say you are replacing the wishbone. I expect this is because the threaded bushes are badly worn and the fulcrum pin in rattling around in them. In this case then the easiest thing for a stubborn fulcrum pin is to cut through it with a mini grinder slotting disc or a hacksaw ( it's fairly soft to cut) cut either side of the kingpin and it won't matter if you damage the wishbone as you are replacing that anyway.

Be careful over buying a replacement wishbone. There are very poor quality ones being sold at present. There is a detailed arrival in last month's MASC magazine by Alan Anstead about what to check for.
GuyW

As for the kingpin itself, although it is hard to tell it doesn't look badly worn at all, and neither does that bush. Are you sure this is where the movement was when you checked it all before disassembly? Was there just lateral movement between the stub axle carrier and kingpin or was there vertical slack as well?

If there was vertical movement I would clean out the old grease etc and reassemble with fresh grease and adjust the small shims at the top of the kingpin. This very often simultaneously takes out some of the lateral movement. But be careful not to get the vertical adjustment too tight or the steering will become heavy.

And remember, the vertical adjustment is controlled by the shims NOT by adjusting the kingpin nut. This must be tightened down fully and either secured with a split pin or use a coconut depending on the age.
GuyW

Coconut? Is this a bit of kit I'm unaware of or perhaps fat fingers?

I feel the need to know Guy.

GN Rowles

LOL. Sorry about that. Blame it on my Not Very Attractive Assistant. AKA Kindle that thinks it knows better.
Although Nylocks are sort of coconut shaped!
GuyW

Drain the milk out first, Bruce.
Nick and Cherry Scoop

Just to add, thanks for all your help.

The refereance to the article was invaluable. I had bought the wishbone from a supplier based in south west london and mine had more weld holes than the one in the article. Complete pants of a part.
I had originally decided to replace the one on there, but due to the poor quality of the replacement I didnt, just chnaged the bushes and put the new springs on.

All put back together. I was feeling quite pleased about it and all I had to do was bleed the brakes. But I ended up ripping a thread so now Ive had deal with that. Arrrrggghhhh.

New thread now made on putting c clips back on...



Bruce Burrowes

Still the complaints about wishbones come in. The complaints are on a par with those about shock absorbers. Lawrence Slater supplied me with some good pictures of the poor wishbones that he had obtained that were then used, together with those from other sources, for one of the Mascot articles on the subject. I believe there is still an article on the subject on the Editor's desk.

I have struck lucky in that I have acquired some original trunnion bushes with which to restore two worn kingpins to 'go on my shelf'.

If visiting motor factors it is often worth asking after old stock as in recent weeks I have picked up some NOS front wheel bearings and some NOS Austin A40 Farina front brake cylinders for my Frogeye which has a period 8" drum conversion.
Alan Anstead

This thread was discussed between 15/08/2018 and 01/09/2018

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