Drop Arm Ball Joint

[AnalogKid]

Not a request for help, just some observations from tackling this job at the weekend, along with an accumulation of useful links I found before starting.

I got knocked back on my warrant of fitness check last week on 2 items, split power steering belt and excessive play in the drop arm ball joint. Now I did the ball joint previously, but didn't manage to get the upper ball cup out, so put it back together with the old one still in because I needed the truck the next day. This time around I was determined to do it right, and equipped myself with lots of info after searching this forum. Here are a couple of useful links with good, clear photos of the bits involved:

The parts involved

Replacing the joint with the drop arm still attached

Replacing the joint with the drop arm removed from the vehicle

Other useful facts:

If you have to take the drop arm off, you'll need a 34mm socket and a big breaker bar. Getting the arm off is a mission in itself. I knew this before starting , and sure enough I sheared the bolts in my 3" two-armed gear puller. In the end a friend came round with a 10 ton hydraulic puller which was loaded up and left for a while. After a cuppa we came back out, but a bit more load on the puller and then applied a 2lb Birmingham spanner to the side of the drop arm. Bang! off it came. A good tip here is to leave the nut on loosened as far as it will go, it stops things from flying off.

The other widely mentioned method of loosening the arm is to loosen the nut slightly (I've seen 2 flats (120 degrees) being mentioned) and then go for a drive. I presume the idea is also to re-bend the tab washer at this point to prevent a nasty accident. I didn't feel too happy about this one. It'd be OK I guess if you had a long, straightish but bumpy private driveway.

If the upper cup doesn't get changed (like when I did mine the previous time, and probably the time or two before that by the previous owner) then the new joint will wear out prematurely. This is one good reason why the job should be done right. Another is because of the problem I had, and why I didn't do it right last time. The more the upper cup wears, the less there will be exposed through the top hole in the drop arm, lessening your chances of getting it out. The instructions in the links above suggest pressing it out with a bolt through a suitable socket. 14mm is the suggested size, but this fell straight through, as did a 15mm socket. I tried a 16mm but the bolt just started extruding the socket through the hole. I thought I would have to take the arm to a machine shop, and this is why I had to remove the arm. Once off, the upper cup was persuaded with an extension bar used as a drift and that 2lb Birmingham spanner again.

One final tip. The job of holding the assembly together while the bottom circlip is fitted seems to cause a lot of bother. With the arm fitted, you can use a jack under the arm and a short extension bar to press it together. I've also tried the caulking gun method as shown on the REEDX site, but this wasn't working too well for me. My friend John who had brought the hydraulic puller just used my old two-legged puller round the end of the drop arm and had the plate depressed and held really firmly in a couple of seconds. That left me with plenty of time to mess with the circlip, but even that is easy if the plate is pressed up and held as securely as it was with the gear puller.

[mmgemini]

I think the REEDX site methods are quite good. I do wish somebody would make a pulller for that top cup......

As for rebuilding. I use an old screw type valve lifter....With a small 3/8" drive socket between the screw and the plate.

Oh yes. Re bend the tab washer.....

There is a better idea...A drop arm from a late 300Tdi discovery with the drag link. That system has a TRE at the drop arm. You do have to make something to hold the steering damper to the drag link though.

[SimonHobson]

I think the REEDX site methods are quite good. I do wish somebody would make a pulller for that top cup......

I made my own, now I've done one, I think more could be made for perhaps an hour of lathe work. I'd post pics, but I left it at my mates workshop . Since I made it I've done one of my own, and two for a friend !
Doddle to do. Plug in top, bolt down, washer and nut on bottom then BUZZZT with the windy gun and 19mm socket. Assemble new cup with bottom plug, bolt, up through arm, washer and nut then BUZZT with windy gun and it's in.

Actually, I have a question about the parts ...
In this article, go to the 15th picture, there are all the new bits. There is one I've never seen before, and it's the one in the bottom row between the seal retainer spring on the left, and what I assume is the smaller (upper) seal retainer spring on the right. It seems the right size to sit on top of the arm under the seal.
Any idea what it's for and where it goes ?

[AnalogKid]

Nope, my kit didn't have one of those.

I wonder if it presses on around the lip on top of the arm to provide a little more positive location for the boot retaining spring?

[SimonHobson]

Nope, my kit didn't have one of those.

I wonder if it presses on around the lip on top of the arm to provide a little more positive location for the boot retaining spring?

Can't see how, the kit I used at the weekend had one, it seems to just sit on top of the seal seating boss.

[mmgemini]

Would you like to make another one please Simon...I don't have a meatwork lathe you see......
There's some cheeky ******es about isn't there....

[wozza35]

I think you should put a piccie up of your tool and then prepare for the rush of people wanting one ,if it makes it as easy as it sounds then i will have one as well

[Stumpy Doofleer]

I wouldn't mind the tool as well, as I tried a few years ago, and I couldn't get the top cup out of the drop arm, and it failed the MOT a few months after I replaced it because of the drop arm ball joint.

[Les Henson]

The ring you mention is top-hat shaped and is supposed to fit in the top to help retain the rubber boot. However, they are very delicate and bend as soon as you put any force on them. They are good for keeping in practice lobbing things from one end of the workshop to the bin.


Les.

[SimonHobson]

The ring you mention is top-hat shaped and is supposed to fit in the top to help retain the rubber boot. However, they are very delicate and bend as soon as you put any force on them. They are good for keeping in practice lobbing things from one end of the workshop to the bin.

Ahh, so it's a tiny frisbee then

[SimonHobson]

I think you should put a piccie up of your tool and then prepare for the rush of people wanting one ,if it makes it as easy as it sounds then i will have one as well

OK, retrieved the tool, here's some pics.

First pic is all the bits.

Second pic shows the order they go in to remove the cup - the smaller plug goes in through the top of the arm, and the big washer goes underneath. 2 seconds with the windy gun and the cup is out. Note that I machined a slight step in the washer to centre it in the hole.

Third pic is the arrangement for fitting a new cup. The cup sits on the step in the plug, the washer goes on top of the arm (smaller step on the washer to suit the smaller hole). Again, 2 seconds with the windy gun and it's in.

The process really isn't any different to those already covered - except you don't have to find a socket that's an exact fit, and chew a step into the outside of it


When I've time, I'll see if I can find a local engineering firm that can turn some out.

[biosbill]

I kno quite a lot of the "hard bit" is getting the new one back together straight and true... but as for getting the drop arm off the steering box/idler, why go to all the trouble of using a puller etc etc.... On looking at the price of a new arm (£4.98 in my case) id just hack it off with the grinder then use a new one... surely thats better than trying to find a big enough puller etc etc. I kno its probably not the "proper" answer, and probably not the best, but surely a solution if you dont have acess to these expensive tools...

biosbill

[gahooduk]

I kno quite a lot of the "hard bit" is getting the new one back together straight and true... but as for getting the drop arm off the steering box/idler, why go to all the trouble of using a puller etc etc.... On looking at the price of a new arm (£4.98 in my case) id just hack it off with the grinder then use a new one... surely thats better than trying to find a big enough puller etc etc. I kno its probably not the "proper" answer, and probably not the best, but surely a solution if you dont have acess to these expensive tools...

biosbill

I thought the were thirty quid each on a defender/Disco

[SimonHobson]

I kno quite a lot of the "hard bit" is getting the new one back together straight and true... but as for getting the drop arm off the steering box/idler, why go to all the trouble of using a puller etc etc.... On looking at the price of a new arm (£4.98 in my case) id just hack it off with the grinder then use a new one... surely thats better than trying to find a big enough puller etc etc

I think you'll find that a fiver will only buy you a replacement ball joint for the end of it - and not even that if you avoid the crappy stuff on blue and white packaging. Yup, check on Craddocks site and drop arms are £32 plus VAT - and that probably doesn't include a ball joint fitted.

You can remove the drop arm very easily with a hammer - one good blow in the right place and it drops off. Trouble is, you can't swing a hammer where required in-situ - a long drift might work if you fit it up past the radiator.

[biosbill]

Hi,

Series steering box drop arm is £4.98 I think, but we're talking about different things.... Anyway thanks for putting me straight as I wondered why nobody had said tht!

Thanks again,

biosbill