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Discussion Starter · #1 ·
Any idea where to purchase these separate from the wishbone arm? They're a piece of cake to remove/refit with a press tool and look like a fairly standard part, but I can't for the life of me find them for sale anywhere (without the wishbone attached)
 

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Any idea where to purchase these separate from the wishbone arm? They're a piece of cake to remove/refit with a press tool and look like a fairly standard part, but I can't for the life of me find them for sale anywhere (without the wishbone attached)
You can buy the rubber boots which usually spilt but not a seperate ball joint which in the past for me have been the issue. Your other options are second hand sombody here will be scrapping a pair for sure or seeing if Demon Tweeks have "universal" job for those building a kit car.

Me given the price of a new arms would go for second hand.

andy
 

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Are they really "that" easy to pop out with a press?

Have you had a go?

Would you be 100% confident that after pressing in a new one, into a hole already enlarged slightly by the pressing in and removing of the previous joint, that it wouldn't let go on some big pot holes?

I wouldn't.

Pat...
 

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Discussion Starter · #4 ·
Are they really "that" easy to pop out with a press?

Have you had a go?
Yep - done with the same c-press as used to remove the rubber bushes. Use the smallest sleeve on the upper side of the wishbone, and a flat plate/17mm socket on the lower side of the wishbone to remove. Use the smallest sleeve on the lower side and a flat plate on the upper side to pop 'em back in. Hold the press in the vice rather than the wishbone, as the wishbone weighs less! Takes ~30 seconds apiece.

http://www.cosic.org.uk/MarkoStuff/handamx5/

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=38335

Would you be 100% confident that after pressing in a new one, into a hole already enlarged slightly by the pressing in and removing of the previous joint, that it wouldn't let go on some big pot holes?
Totally - there isn't any vertical load on the upper balljoint. Vertical/bump loads go through the lower wishbone and the spring/damper. The only vertical load on the upper wishbone is from the upper wishbone bushes and the inertia of the upper wishbone itself if you think about it - and you can move that by hand so its minimal - which is why its just a pressed in part. (its actually *less* of a press fit than the rubber bushes...) Vertical force to deflect the rubber wishbone bushes is <0.5kN and I'd guess at about 5kN to press the thing out. In use the balljoint will only really ever see side-loads from braking/lateral loading on the tyre, and braking is dominant.

For comparison in braking/cornering: if you assume that all the weight of a car loaded to 1500kg is on the one wheel, and that one wheel is 0.5m in diameter, then a 1g braking move is 15kN longitudinal loading plus 3750Nm braking torque on the balljoints. Spacing between them is around 0.3m, so that torque is the equivalent of 12.5kN on each balljoint. Adding this up the bottom balljoint gets hammered with 37.5kN and the upper 12.5kN. In cornering it'll just be 12.5kN on both of them, as there's no brake torque. Note that the bottom balljoint always carries the weight/bump loads up to the spring/damper and chassis too.
 

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Yep - but that's retained in case of failure with a circlip.

Each to their own.

Pat...
 

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Discussion Starter · #7 ·
Yep - but that's retained in case of failure with a circlip.
The circlip isn't there for "failure" of that balljoint on the RX7 or 929:

When you're using the balljoint as a lower balljoint (as on the RRX7/929, pressed through from the bottom) the flange carries the "bump" loads into the spring/damper and the circlip carries the "rebound" loads into the spring/damper.

The upper balljoint doesn't see vertical loads so doesn't have the circlip.
 

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i take it you're from america then marko? harbor frieght stuff's usually a bit pricey by the time it gets across to us

i'm intrigued by your suggestions on the balljoints. looks good to me and assuming the balljoints are the same, the shoulder will make them captive in the wishbone even if they do unpress themselves, so a relatively safe failure.

let us know how you get on
tom
 

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Discussion Starter · #9 ·
i take it you're from america then marko?
Wales-Cambridge-Boston-Cambridge-Wales-San Francisco-Wales-??Sheffield?? whatever that makes me!

harbor frieght stuff's usually a bit pricey by the time it gets across to us
Tell me about it - *everything* is pricey over here...


The c-presses also seem to be something that you just don't get here. Thinking about renting mine out like that chap with the arch-roller. 50 quid deposit, 8 quid to ship it outbound with parcel2go, 10 quid rental, 8 quid to ship it back, call it a round 25. Worth it if you're doing polybushes perhaps as a one-off, else you'd be better off taking the 25 quid and putting it towards one of your own. (or taking 'em to a local machine shop to swap out)

I'm intrigued by your suggestions on the balljoints. looks good to me and assuming the balljoints are the same, the shoulder will make them captive in the wishbone even if they do unpress themselves, so a relatively safe failure.
Exactly. Dab of loctite and they'd never go anywhere. (unless you heated them first to break the bond) Will let you know. :)
 

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sheffield.....cool. you should get yourself to the next tech day at rodders', or the meet in leeds if you fancy venturing that far.

sounds like you'll fit in well. challenging the status quo but in a well reasoned fashion
tom
 

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Discussion Starter · #11 ·
sheffield.....cool. you should get yourself to the next tech day at rodders', or the meet in leeds if you fancy venturing that far.
We'll see! Need to find a 5 first (only have a bike at the minute, and doing some work on kid bro's 5) and a place to live in Sheffield.

sounds like you'll fit in well. challenging the status quo but in a well reasoned fashion
I'm always the square peg.


Stuck a Rover 220 'Tomcat' Turbo engine in the old Land-Rover in part because of insurance (insurers were perfectly happy for a 17 y/o male to put in any engine he liked so long as it was smaller than the original, even the force-feeder was set to 11...) and in large part just to annoy the boys with the diseasels and the V8s who said it'd never work


http://www.cosic.org.uk/MarkoStuff/Land-Rover%20T-Series/Series%20Land%20Rover%20T16%20Turbo%20Conversion/target53.html
http://www.cosic.org.uk/MarkoStuff/Land-Rover%20T-Series/Series%20Land%20Rover%20T16%20Turbo%20Conversion/target54.html


MK Indy I take it? Fancy a CBR1000RR motor/exhaust/wiring/ecu/dash and all the trimmings (incl the prop adapter) for it? Bought in the US to stick into an MG Midget but that got canned with the move back and lack of company workshops now.
 

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Ahhh - it's been explained to me now.

Didn't realise the top balls had a shoulder on top of the bone and will be bolted to the upright below, so even if the press fails, they won't collapse.

You go fella,

Pat...
 

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np Pat :)

Wishbone with the joint pressed out:





Balljoint:







Press-in (custom) replacements from the V8 roasters folks in the States: ($75 each)



http://www.v8roadsters.com/product-p/fuball.htm

Dimensions of the joint:





I'll be harassing some parts counter monkeys, but in the meantime you can most certainly repair/upgrade the front upper wishbone balljoints for $75/corner.

I'm banking on it being an RX7 part though, so might be available for just a tenner...

http://cgi.ebay.co.uk/LOWER-BALL-JOINT-TO-FIT-MAZDA-626-RX7_W0QQitemZ380217534124QQcmdZViewItemQQptZUK_CarsParts_Vehicles_CarParts_SM?hash=item5886bb26ac#ht_500wt_956
 

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Quality mate - all makes sense now.

Pat...
 

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Do you have any info on the length of the taper as that is critical to getting the right angle? Reading the desciption on the V8 Roadsters web site, one wonders if the ball joint they offer was commissioned rather than from a manufacturers parts bin. But still $75 is a lot less than ?168 for a new arm (or whatever outrageous cost it was).
 

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Discussion Starter · #18 ·
Tricky without destroying the boots on the ones I do have. I'll see what I can do measuring the uprights themselves. Should be a fairly std angle I'd have thought.

Azura - wasn't planning on. Just wanted to find the bits and let folks know that it can be done. You can get it done by anybody local with the most basic of presses then. If I were to do anything as a service it'd be offering a complete set of refurbed wishbones:

Take std wishbones
Sandblast/acid pickle
Hot-dip galvanise (or galv then powder coat - but powder coat on its own is shit)
Fit new balljoints
Fit polybushes (or new OEM bushes)
Supply with an all-new set of bolts for quick swapover (you can just cut the old ones off then)

Trouble is it'd cost a "small fortune" to do and I doubt many would be interested. Say the wishbones are free (you always get straight ones for exchange). Sandblast/acid pickle/galv then chase the threads out with a tap would be 150 quid odd. Balljoints 100 quid the pair. Polybushes are at least 200. Lord only knows how much a new set of bolts is from Mazda. Probably IRO 200 quid. Would anybody pay 800 quid for a set of wishbones/polybushes?

You could offer sandblast/powdercoat on its own and new balljoints for 250 exchange, but then the punter still ahs to buy the polybushes, press 'em in themselves, and wrestle with the old bolts, and watch the powdercoat crack/wishbones rust again.
 

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Trouble is it'd cost a "small fortune" to do and I doubt many would be interested. Say the wishbones are free (you always get straight ones for exchange). Sandblast/acid pickle/galv then chase the threads out with a tap would be 150 quid odd. Balljoints 100 quid the pair. Polybushes are at least 200. Lord only knows how much a new set of bolts is from Mazda. Probably IRO 200 quid. Would anybody pay 800 quid for a set of wishbones/polybushes?
if you can get the ball joints for ?100 the pair tell us where..please.
ive already polybushed alas not the top ones.
 
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