Ken - there's lots of ways of doing this. You pay your money and take your choice. For a concours car I was going to keep for a very long time, having it done in an engineering shop would be my choice. For a daily driver then I'd probably run the MIG over it as you do.

I do think the Citroen design, relying as it does on an interference fit, is a very poor one in terms of longevity and servicability. The 1932 Ford axle on my 1921 Model T hot rod was dug out of the floor of a barn where it had sat for decades after a second life as part of a homemade tractor. A new Ford licenced kingpin set (much cheaper that the Citroen one) was fitted with no trouble whatsoever and it is ready to do another 79 years of service. The original Model T axle was in similiarly excellent condition and could have been used but 300BHP and no front brakes is not a good idea. The Citroen design means that components from the late 1980's are unservicable. Backyard mechanics working on those 1930's Ford kingpins are just as heavy handed as those working on 1980's Citroens. It was supposed to be capable of being maintained by farmers and one of the key tools is a 5lb lump hammer. My in-laws are all farmers and if you give them a hammer and some delicate machinery the outcome is inevitable . So it comes back to design - how many perfectly good A Series have been scrapped because of kingpins?

I'm certainly not criticising the system you have developed - it's keeping cars on the road that would otherwise be scrapped by owners who can't afford the machine work to fit o/s kingpins or don't want to take it off the road for the time it takes.

The recesses for the threaded plug and the welch plug would be bored out on a Bridgeport - not using a handheld grinder. So they are very unlikely to end up tapered. The line boring - sorry I wasn't clear on that. What I meant was the arm would be set up with the top surface parallel to the table of the Bridgeport and then reamed to size on the machine - so that there's no chance of the reamer going in cockeyed.

Sorry for the rubbish mobile phone quality picture - but you can see here the crucial difference between the Ford and the Citroen kingpins. The Ford has a hole for a cotter pin. This tapered pin holds the kingpin tight without the need for an interference fit and means there's no need to attack the kingpin with a lump hammer when time comes to replace it. The only special tool needed is a reamer. The bushes are fitted top and bottom with a drift and then they are reamed with a Ford reamer that has a pilot to ensure they are in line.

I don't see any problems grinding away as long as the top bush and pin is not removed. This is not in anyway cutting in to the hub
Only the 4 folded over locking chips are removed. When the plug is flatten it seals the top.

Very neat work. I think the kingpins on my car have been replaced at least 3 times (i.e. 12 "tabs") so the amount of material available for locking is now minimal.

I will have it milled out and turn up a stainless plug to include an O ring.

Every time you grind the metal away there's less of it left for next time, after a few kingpins the hubs bollocksed because there's not much metal left. I reckon that's a cause of leaking welch plugs.

My take on this 'problem'.
The metal of which the hub carrier is made is malleable, so those tabs can be knocked back with a drift, rather than be ground away.
Also, a centre punch is adequate for staking the edges after a new Welch plug has been fitted, especially as the staking is supplementary to the principal method by which a Welch plug achieves its seal.

http://www.engineproblem.com.au/welch.htm

ken

ha ha ha.... my take.

a lump hammer is a cheaper tool than a reamer and has more uses and easier to use, welding trick was from the Austin7s club, avoid removing metal as there will be none left soon. and in the next 20 yrs a neat bead of weld on the arm isnt going to affect the price one iota! (however having a worn pin that's impossible to remove cause some Johnny has plug welded it in will) just look at the poorly tack welded and "bondo" filled poor repairs by so called "professional" repairers and they aren't shy in asking top price for their work.

dont think Citroen originally envisioned their cars keeping going 30 odd years, the original bushes lasted ages therefore fit for purpose id say. The steel ones now just wear the pins

Ill carry on welding with a clear conscience

Half a house brick is even cheaper and can be used to build a house when you've finished using it to maintain your car. Seriously - why wouldn't you want to buy nice tools. He who dies with the most tools wins.



Probably not for daily drivers but when you're spending big bucks on classic cars everything affects the price - and the top class 2CVs will be very expensive in 20 years. Daily driver 2CVs will be few and far between in 20 years.

unless the bubble bursts
stupid prices attract speculators and in that rarified atmosphere things get even more stupid

there's more to worry about with a 2cv than whether the kingpin is a virgin one ...in fact my orange one is on originals , all be it worn to the point of needing replaced- for a new set that will have the same amount of play "out the box" (in fact may even try the first oversize in the standard bushings to see how they go )

[quote="blackjack the Citroen 2CV kingpin system is just not very good. I don't understand why the the pin fits in the eye with an interference fit. The Ford system uses a cotter pin to hold the kingpin in place in the eye and the bushes come over-sized for pressing into the hub carrier and they are then reamed to size. [/quote]

There is nothing wring with the Citroen system, the problem comes with people who don't understand it replacing the king pins annually. Indeed they're far easier than most king pins precisely because they don't need reaming; the bushes are pre sized.

I found myself arguing with someone a while back. Their early 60s van they'd just bought was still on its factory king pins. They wanted them replaced "because 2CV king pins are never any good". As it happens they were still perfectly serviceable after 50 years.