Texas Meet Reg.

The old ones are a BIG PITA to get out... looking for suggestions...
Thanks!
Ryker

turborexron

The old ones are pressed in, just like the new ones need to be. I would say have someone do it for you, that has access to a press, that would be the best tip, good luck with it.

NewbernD

iTrader: (1)

I wouldn't even think about beginning this job without access to a press, with a variety of sizes of heads/slugs/large sockets to press with. Because the centers float in rubber, you'll have to really load up on them before they come lose.

Having the car on a lift made things a hell of a lot easier, too.

You'll beed a BFH (big effing hammer) to break the ball joints loose with.. don't waste your time (or your $500 ball joints) with a pickle fork.

Might as well press in some pillow ***** while the suspensions is coming apart. They're about $50 each (6 total) and you won't know how many you'll need until it all comes apart.

Are you installing zerk fittings? Get a drill & tap, and some good grease to install with. And be sure to lube up every surface of the pins and the interior of the bushing before you install them.. You don't want any dry spots in there..

wonder1and

Yep doing the fittings and already have done the pillow ***** in the past... just need to follow up w/ the rest... thanks guys.
Ryker

Ring Steel

I thought the factory service manual showed a set of hand tools intended to remove and install the bushings? Is a press really necessary? I don't know a competent shop locally, and I think that it would be easy for an idiot to screw up the front arms if he had 40 tons of pressure the play with.

Wargasm

I have a set of the Mazda hand tools (bushing install set) on order... but it's been weeks.... I think they are coming from Japan.

Brian

93 R1

how much did that cost?

JimmyJimboJet

check out max cooper's site. he has a writeup on bushing replacement

Wargasm

Justin, I dunno... something like 300 bucks. They should be here in a week or two according to Malloy.

NewbernD

iTrader: (1)

Yeah, I started out going that route.. got my all thread and a couple handfuls of washers... Thankfully my brother called me up, and I went over to his shop to use the lift and the press.

You should realize that these bushings are not quite the same as the pillow ***** on Max's site, though.. and while one could probably get them out with this same method, I don't think there'd be much left of your hands after ratcheting through the first couple. They require a good but more oomph to press out, and since they're not solid (rubber centers) you have to have a pretty exact-fit on the bushing sleave or you'll be pressing on rubber.

Ring Steel

Wargasm,
After you get the tools and use them to replace your bushings, I BET you can sell them real easy to the next guy who needs them. Hint. Hint. Can I be first on the list?

wonder1and

I asked $360 bucks... from mazduh... I found another tool that I though I may be able to use but you have to hammer the bushings out. Searching for page now... I didn't think they would be very useful. Or should I say very difficult.

I found this to be interesting...
http://www.humanspeakers.com/audi/bushings.htm#late

also
http://buy.snapon.com/catalog/pro_de...re&dir=catalog

Hmm...
Ryker

purplelimo

I'm having a hell of a time popping off the front lower control arm on the passenger side.

The driver's side I was able to pop off using a pitman arm puller from Harbor Freight:

http://www.harborfreight.com/cpi/cta...emnumber=36865

I tried using this puller on the passenger side, but it just breaks the puller--in fact, I broke 2 of them. I've tried using lots of liquid wrench, pounding on a nut on threads with a 4# hammer, hitting the hub carrier with a 4# hammer and heating up the carrier with a propane torch. The ball joint seems to be pretty seized in there.

Anyone have any suggestions on what else I can try? I've wasted many hours on this one arm already and I'd really like to just pop it off so I can get on with my life.

wonder1and

I'll post tomorrow...I'm doing my front bushings when I get up... if my friend will let me use his press at his work...

NewbernD

iTrader: (1)

Purple Limo.. Here's a thread with some tips..

https://www.rx7club.com/forum/showth...ht=pickle+fork

It really just takes a 5 pound hammer and a few minutes. You preload the lower arm by trying to hyper-extend the ball joint (hold the lower arm all the way down), and then whack the arm (not the threads) at the joint. Whack it again. One more time. If it's really stuck, a little heat from a propane torch will help the aluminum expand (faster than the steel ball joint).. just don't cook your ball joint.

Good luck,

purplelimo

When you say whack the arm, do you mean the actual control arm or the hub where the ball joint is pressed in? I've tried whacking things are various places and I've also tried applying heat to the hub (which is cast iron btw, not aluminum) but the ball joint will not pop loose. It is seized in its hole pretty good.

purplelimo

Any other suggestions on what I can try?

jimlab

Spray some WD-40 or another penetrating lubricant on the ball joint shaft.

Remove the castle nut (21mm) and turn it over and then thread it on until the bottom surface is flush with the balljoint shaft, or find a suitable "throw away" nut and do the same thing.

Apply heat to the cast iron steering knuckle with a propane torch a bit at a time, and with a mallet, give the joint a "whack" directly down onto the nut. The nut will protect the threads, but only if you hit it perpendicular to the shaft. If you hit it off-center, you're going to screw something up.

Don't apply too much heat, or you may gall or damage the ball joint, and that means a new lower control arm.

A little heat, a shot with the mallet. Maybe a little more WD-40. Eventually they'll loosen up and pop free. The nut over the threads also keeps the lower control arm from shooting loose when the ball joint shaft does come free of the knuckle.

Be patient. The longer the parts have been on the car, the harder it is to get them apart.

NewbernD

iTrader: (1)

Thanks for filling in, Jim. Sorry for the delay.. work's been nutz.

You're right, Purple, the hub is cast iron.. My bad. It's been a while since I was down there. We would always put pressure on the joint by rotating the control arm, and then whack the control arm at the joint. I guess if you hit the nut, it'd work too but I seem to remember there being not much room for a good, clean hit. And I'm always afraid I'll mung up threads.

jimlab

There's not that much room, but it's not necessarily the force of the blow that will break the joint loose, it's the vibration. I use a 2 lb. mallet, sideways (hitting on the side of the head, not the face) and only raise it as high as the top of the knuckle. If you come in at an angle from the side, you're almost sure to damage the threads or nut.

BTW, after my engine cradle and other fabrication work is complete, lower control arms with replaceable ball joints are one of my next projects.

NewbernD

iTrader: (1)

That's what I'm talking about...

Those going to be before or after the headlight kit, the cobra diff kit, the drop-in v8 kit, ...I'm sure there's at least 2 more kits..

By the way, the new bushings look nice.. although not very forgiving. The more I thought about it, I was almost certain you were going to use some sort of roller bearing in there.

jimlab

My engine cradle, differential cradle and headers are being built right now. Once one or two of those are finished up, I'll be talking to my fabricator about building control arms. I need to find a nice, cheap domestic ball joint that screws or bolts into place that will work with the RX-7 knuckles.

They won't be forgiving at all as far as deflection is concerned, which is precisely why I wanted them. However, they're not supposed to soak up jolts to the suspension. The springs and shocks are supposed to handle that job and the bushings are only supposed to act as pivot points.

While the stock rubber bushings may contribute to soaking up some of the jolt to the suspension caused by overly stiff springs and shocks and low profile tires, it's not a desireable thing, because they're allowing the suspension to move out of alignment while they do it. The main purpose of using rubber is to dampen road noise and vibration, not to absorb bumps in the road.

The point is to allow the shocks and springs to do the job they were designed to do. With less deflection, you can set the shock valving softer and/or run lower spring rates and still have complete control of the suspension, because it's not twisting out of alignment on every bump you hit.

The only downside is an inevitable (but hopefully low) increase in NVH (noise vibration harshness). I don't think these bushings are going to transmit significantly more noise than the Nylon bushings, but there may be some noticeable increase. Then again, I didn't notice a significant increase in noise from the Nylon bushings in the cars I've ridden and driven which had them installed.

BTW, for anyone who hasn't seen them, here's what we're talking about...



From left to right; an OEM rubber bushing, a new pillow-ball bushing, and an Unobtainium Nylon 6-6 bushing for the front lower control arm.

Note the abundance of rubber on the stock bushing allowing substantial "slop" in the suspension. The Nylon bushing has some give, but far, far less than the rubber bushing. The pillow-ball bushing uses the same design as the OEM pillow bushings in the rear lower control arms, and shouldn't have any "give" at all.

In the picture below, you can see the articulation of the pillow bushing demonstrated in comparison to the fixed-axis design of the OEM bushing on the left and the Nylon 6-6 bushing on the right. These are inner bushings for the rear upper control arms where they bolt to the rear subframe.



The net effect is the same as having a rod end (like the M2 toe links and trailing arms) race-bred suspension for perfect suspension accuracy, but the pillow ball bushings spread the load over a significantly larger area than a rod end and have dust covers to seal out grit, so they will last much longer than a traditional rod-end joint. Service life should be about 70-80k miles.

FAQ...

1. Yes, they were horribly expensive.
2. No, you can't have any. There's only one set.

NewbernD

iTrader: (1)

Not to completely hijack this thread, but...

I'm surprised to see that that you've chosen a solution with more than just one axis of movement for this. Especially when they're paired up, like on the front control arms, they're shouldn't be any other direction of monement, should there be? Not that I'd expect there to be a problem from using a bearing as a bushing like this, but it just doesn't seem like it would buy you anything as they'll never need to pivot.

Maybe I am just missing the obvious. I'm sure you've looked at this particular setup much more than any other non-mazda human.

purplelimo

How much heat is adequate vs too much? Is 45 seconds to a minute with a propane torch good enough for each "shot"? Or should I heat it up more?

jimlab

The "triangulation" of the control arms will keep them from pivoting. It would be impossible to move the lower control arm towards the front or rear with both bushings bolted in place, for example. You could pivot one bushing, but not both at the same time. Make sense?

In order to make one of the bushings pivot, the rear bushing would have to move outwards with the control arm, something it obviously can't do when bolted in place. The pivoting is not necessary for the range of motion of these components, but using a pillow bushing design does mean that the individual bushings can pivot, although they will not be required to.

The only goal was a strong metal-on-metal joint with more surface area than a rod end, which will rotate in only one axis, just like the stock bushings. The pivoting was only demonstrated to illustrate the internal construction of the bushings. Hope that clears things up.

Absolutely true. I should have clarified that the pivoting of the bushings was not a necessary feature, just a "side-effect" of the construction.