8 replies to this topic

[bikenutmart]

Hi, Been doing my front ball joints this afternoon, pretty sure ive got the top ones shimmed ok, the bottom ones are giving me a problem, if I correctly shim them( without the spring) then fit the spring as per the Haynes manual, the pin goes almost solid! to get the correct amount of movement with the spring fitted I have to overshim them(too loose) and then when the spring is fitted they feel right. There is obviously a reason why there only a spring fitted on the bottom, does it compress when the weight of the car is on it? I bought the kits from minispares so the quality is decent. Ive done the top pins so they move with a thumb push, and don't bind, as I was warned against doing them too tight, any help much appreciated. Cheers Mart.

[Cooperman]

I always just put the lower one in with the spring, then nip it up and see how it feels. I add or remove shims until it is just possible to move it with thumb and a finger. In over 50 years of doing it this way I've never had a problem.

[nicklouse]

 There is obviously a reason why there only a spring fitted on the bottom, does it compress when the weight of the car is on it?.

nope.

look at the swivel hub. the cup sits in a cut out and that is what you shim to. then when you put the spring in the cup is then also seated in the cut out correctly.

 

As to that actual job that the spring does that is an interesting one as it really does nothing when the wheels are on the ground. but if you do lift a wheel off the ground it applies force on the cup if there is any wear and maybe reduces noise.

 

it is interesting as there is the same machining both top and bottom which makes me thing that originally there were springs on both ball joints but it was found that one did nothing so was done away with. this is pure speculation but is something I have often wondered.

[Alpenflitzer]

It depends what ball joints you have. Do they have 1) a groove cut in for the grease and 2) did you grind them?

 

If you search in Youtube for  Classic Mini ball joints you should find a video where a guy demonstrates how he grinds the ball joints.

Important is a small groove so that the grease has a way to go.

 

have a look here:        https://www.youtube....mini ball joint

Edited by Alpenflitzer, 19 January 2016 - 05:01 PM.

[bikenutmart]

Thanks for the quick replies everyone! Yes there is a groove, do you mean to grind them in like you do with valves?

[GraemeC]

The spring keeps everything snuggly together, pin against the seat and pin against the outer cup.  Don't need one at the top as the weight of the car does the job.

 

It is normal for the spring to add enough pressure for you to be no longer able to move the pin.

[Fast Ivan]

shim them so that there's between no nip and .003" end float, when the spring is fitted it will tighten the whole assembly up - this is normal

[bikenutmart]

That's great!, thanks for all the replies. Mart.

[jaydee]

Do not grind the ball joint, just gently lap them with fine paste and oil/grease, preferibly by hand.

You dont want to cut through the hardening, really.

When lapping your aim is to to fix some small high spots-flaws so the joints move smoothly in the cup/seat.

Edited by jaydee, 20 January 2016 - 11:24 AM.