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Mark N
20-06-2011, 04:08 PM
I receintly had my wheel alignment checked and found out the nearside caster is out of tollerance.unfortunatly the caster adjustment is seized solid .I have been told the easiet way to free it up is to remove the pivot assy.:no: unfotunatly after five hours of gentle coaxing i still can not get the upper and lower ball joit to release from the pivot assy:angry: am i overlooking something or doing something wrong :unsure: any help or advice would be greatly accepted.

Mark

Nick Graves
20-06-2011, 04:16 PM
Kaz has recently done a thread on how to separate the castor cup in situ.

Lots of Plus Gas, rags in hot water & some freeze spray. I'm sure similar might loosen your balls.

I tried it on my caster cup, but it didn't work, sadly. The problem is since it's all aluminium, I'm scared to t wat it with a big hammer in my usual precussive style.

Mark N
21-06-2011, 07:28 AM
[lots of Plus Gas, rags in hot water & some freeze spray. I'm sure similar might loosen your balls.

:laugh: Thanks for the tip i will give it a go.I was going to try the freeze spray followed by industrial hair dryer for the heat. Failing that it might have to be more radical measures:beatdown:

Mark

Nick Graves
21-06-2011, 09:20 AM
Just bear in mind that the middle of the compliance pivot is rubber (plastic) and you don't want to melt it.

Ditto the dust covers on your balljoints.

Ps - my compliance pivot is now as clean as a medical instrument. But still seized.

Kaz-kzukNA1
22-06-2011, 01:07 PM
Hi, Mark.

Before trying to disassemble the compliance pivot, please note that factory alignment setup is based on the assumption that you are using the factory rideheight, OEM tyre on OEM wheel and so on.


I don’t know the latest chassis package and setup you have but if I remember correctly, you used to have quite aggressive setup (with aftermarket LSD??) so factory alignment would be just a starting point.


By the way, on top of these, static alignment is nothing when looking at the dynamic behaviour of the chassis including the weight distribution and the tyre movement so you will need to customise the setup based on your needs.

In fact, any discussion about alignment for the street driving condition is not [easy] (couldn't find suitable word.... thought about using [means nothing] but ... ) as there are so many factors changing every second.


NSX has huge caster angle from the factory and while it has the camber effect on turning and also steer recovery, quite often, you can achieve reasonable amount of caster even if it is out of the factory specified range.


The golden rule is to achieve the same/similar figure between the Right and Left if you can’t achieve the targeted (or factory) figure unless you are racing your NSX at the oval circuit.


As mentioned above, there is no point in talking about the static alignment figure without knowing your package, demands and driving conditions but just as a reference, if you can achieve more than about 5 – 6deg caster and the same figure between the right and left when you are at your targeted camber and toe, you should be able to drive your NSX without noticing the reduced caster effect.


For your reference, I use different setup and package compared to the factory ones and I’m using only about 6 – 7deg caster which is well out of the factory range.

I’m even thinking about making the pivot solid (locked) for high G braking situation.


If you can’t achieve the same caster value between the right and left then due to the way the pivot moves, in my view, it is more important to aim for the same wheelbase between the two sides than trying to adjust the caster.


If you are really struggling with the pivot OH, one thing you can try, but please note that I haven’t tried it on the pivot yet and thus, I have no idea on what effect it will have with the special rubber bush inside the pivot tube/tower.


I learnt this method from the member Graham and he successfully removed the seized camber adjuster bolt.


I also tried it on one of the 20 years old seized driveshaft spindle and manage to push it out from the hub.

It was also very effective on the rusty/corroded brake pipe fitting where it is connected to the brake hose inside the wheel arch.

You can read it in the following links;

http://www.nsxcb.co.uk/entry.php?219-Seized-bolt-and-nut-%E2%80%93-info-from-our-member-%E2%80%98Graham%E2%80%99

And also;

http://www.nsxcb.co.uk/entry.php?225-Drive-shaft-02


As the cup sits vertically and there is very little gap, not sure how effective it is but if you can carry out the risk assessment and happy with it, then you can give it a try but please be extreamely careful with the handling of this liquid.

I would love to try it if I can have access to a spare seized pivot….

Kaz

Nick Graves
22-06-2011, 04:12 PM
Acetone was the main ingredient in cellulose paint thinner & nail varnish remover.

I was very slapdash with it and remember sliding about on molten trainer soles sometimes. I used it as hand cleaner, but I'd probably not recommend it now.

I think the main problem is actually getting penetration in situ - the cup is a real precision fit and there's hardly any gap at the top.

It's such a bloody awkward shape too. I think what's needed is a kind of hub puller that can twist slightly over the bolt tabs and then apply a gentle, straight pressure on the bolt in the rubber bush. The slightest off-pull & the cup will tend to bind.