(STEERING) Idler Bushing Problem Illustrated
 

I took some pictures to illustrate the common Idler Arm Bushing problem all 1st gens get over time. First is a GIF animation of the floppiness of the idler arm with even one bad bushing (there are two of them; top and bottom):

https://www.rx7club.com/forum/attach...d=158947&stc=1

The symptoms are a tendancy to wander in freeway ruts (even if the stering box is fairly tight) and particularly an odd cornering transition feeling, like the tires are rolling over. Braking can be skittish. You might also get a little clunk or groan when driving over a curb-cut at an angle, like pulling into your driveway. What's happening is that the tire toe is changing. Once you are in a corner the steering settles down, because only the outside tire is loaded.

Here is what it looks like inside:

https://www.rx7club.com/forum/attach...d=158948&stc=1

And the arm:

https://www.rx7club.com/forum/attach...d=158949&stc=1

As you can see, the bottom bushing is still intact but the top one had turned to mush. I scraped out the mess, applied some bearing grease and installed new bushings. I replaced both because it would be stupid to do only one while I'm in there. Here is the bag of replacement bushings, so you can see what they look like and note the part number.

https://www.rx7club.com/forum/attach...d=158950&stc=1

When i replaced mine i didn't get it tight enough at first, so it developed that sloppiness. I had to take it back off and tighten it down more...something to watch out for.

Rich

Almost forgot. Here is a picture showing where the idler arm is and what it does. As you can see, the idler arm mirrors the steering box arm. It is needed to keep the geometry correct. If the idler arm is flopping around, the wheels will change toe (point in slightly different directions) making the car handle inconsistently.

https://www.rx7club.com/forum/attach...d=158977&stc=1

Nice Job.

Here is the REAL Solution. One time, and for good.

HEAVY DUTY Idler Arm Replacement.

http://www.mazdatrix.com/pictures/h-susp/hdidler.JPG

Heavy Duty Replacement Idler Arm
These replacement idler arms use ball joints rather than bushings, we use these in all 1st gen race cars.

http://www.mazdatrix.com/getprice.asp?partnum=MOOK9369

:icon_tup: GREAT INFO thx

I have always wondered about that
Thanks!

When you tightened it up did you do it with the car on the ground? (thats how you are supposed to do it), at least thats the way we teached us to do it at college.

I find is curious that it uses a ball joint for the inner joint...or perhaps I misunderstand. That joint needs to rotate about a fixed axis; not pivot. Pivoting is what happens when the stock bushings fail, and that causes toe changes. Again, perhaps I'm not quite understanding the geometry of their solution. I've seen several different approaches, like bronze replacement bushings as well. One I'd like to try is to have the housing machined out for tapered roller bearings. Anyway, I'm not sure it's worth contemplating too much. If good, stock idler bushing aren't good enough, the answer is not improving the idler but replacing the recirculating-ball steering with rack-and-pinion. Why take half-measures?...unless you are racing and have rules that limit your choices.

^English major

Anybody know of where poly bushings could be easily found?

here
http://www.mazdatrix.com/hsteer1.htm

and other places as well I'm sure

Those are stock replacement, not polyurethane, though if I can't find any poly ones easily, I'll probbly order those anyway.

shit, I see. I have no idea then

I like the idea of machineing for roller bearings. The link works just like the front forks in a bike frame. So it would be cool to see something done along those lines.

I'll look into the options, but like I said, it is hard to justify. Just a quick look at some standard references didn't show anything close to dropping in, as far as tapered roller bearings go. Perhaps I'll find something in a machine tools catalog. Metal bushings look much more likely, as oil impregnated bronze is readily available and machining it would not be complicated or expensive. Not sure what the stock plastic bushings are, but it's probably not bad for the application...Mazda engineers aren't chumps, though their bean counters sure are.

uhhhh can you send me a pm how to install it, cause that now looks like a requirement for me :crying:

Thank you, some of us mechanics aren't Shakespeares. (and I didn't proof read it, I guess its pretty offious)

^^^ pretty offious ... doh! but we all need to improve somehow.. oh wait, is that a Canadian word? no.
Just kidding Shaekespeares Dan!!!:)

Very cool animation!

I just did the installation 3 weeks ago. I had a bad idler arm busing that disintegrated due to the heat of my exhaust. My car now has extremely tight and concise steering.


The new replacement from Moog is literally a replacement for the whole
idler arm setup. Not just a little bushing.

It was like 4 bolts. Nothing more. It even comes pre-greased.

When you're looking at the old one, you'll see how easy the new one
takes its place. It's a quick bolt in affair. The longest part is jacking up the car.

Link to Moog part please.

Mazdatrix Link in my original post.

How do you get the old idler arm off the drag link? In the Mazda manual it talks about a two jaw puller. I have one but can't get it to fit properly. I also tried loosening the castle nut and beating it a bit but that wasn't doing much either. I don't care about the idler arm itself because I have the replacement but I don't want to kill the drag link. Any ideas?
Btw, my idler I got from Napa (can't think of the brand but I'll let you know after the next time I go to the shop) and I believe I ordered heavy duty but it came with blue (I believe poly) bushings. Looks very strong but maybe not quite like that greaseable one.

Darren

Place a jack stand under the castle nut and pound down on the drag link. Be careful not to bend it. Penetrant and heat will help also.

A pickle fork will do it too.

Lots of great info here guys-
thanks!!!
Stu Aull
80 GS
Alaska

Thanks a bunch trochoid. I also just got back from the store and picked up a thinnder three jaw puller instead of two jaw. Needed one anyway so I'll give it a try... If not I'll approach your method.

Darren