bliffle

I hit a steel access cover that was up on the road (about 12" diameter and 6" high, with Water Co. markings) while going about 10mph in a residential area, but now the right-rear caliper is dragging on the rotor. Took off wheel and found rotor scored all the way around on the outside, zero clearancebetween rotor and caliper at the top, Fresh metal shavings laying on top of caliper. About 3/32" clearance at the bottom. Rotor is scored all the way around. Can't rotate wheel or rotor because it's obviously jammed.

Looks like caliper must be bent or knocked out of adjustment. It seems to be cocked because the 3/32" clearance at the bottom of the caliper seems to be normal..

Is there an adjustment? Could it just have been knocked out of adjustment? Then all I need is a new rotor.

Is the axle bent? Wouldn't the scoring vary around the rotor? Wouldn't it change as the wheel rotates?

I'm thinking that I have to loosen that caliper and see if the rotor wobbles as I rotate it. But how do I do that? FSM time.

Kentetsu

Yeah, it sounds like you're going to have to pull the caliper and see what got bent. Maybe just a slide pin or something simple Good luck...

steve84GS TII

Sounds like the housing might have bent.

If the axle shaft or axle flange had bent,then yes the rotor would wobble as it spun and the rubbing would vary.
But if the housing got bent,then the calipers position relative to the rotor would change.The axle/bearing/rotor/wheel assembely can move and shift around a little bit in there,its common for racers to bend a little camber into the housings and not have any wheel bearing/axle problems.
But the caliper is bolted directly to the axle housing,so it will move a fair bit with any housing distortion.Look for where its rubbing and see if you can shim the caliper out a little,or as a last ditch effort,you might be able to bend the caliper mounting ears on the housing in/out a little, with a few hammer blows.

bliffle

It's jammed tight so I can't rotate the rotor, but as I drove slowly the 1 block home (luckily) it scraped consistently, so there was no evident wobble.
That caliper is a big stout looking piece, so I can't imagine that it bent, but perhaps what it attaches to has bent. Is that just the axle housing?

Or maybe the caliper got shifted in it's mount to the axle housing.

I'll try banging with my big hammer as a last resort.

The Haynes FSM doesn't say anything about the rear disc brake cars.

Does anyone have a proper SE manual?

Sgt Fox

iTrader: (3)

I have heard that I may have manuals on my site: http://rx7.foxed.ca

bliffle

Thanks, Sgt Fox. Got the brake and axle pages but the scan is a little spotty. I'll take a closer look tomorrow morning.

Siraniko

iTrader: (13)

you better find a new optometrist.

Sgt Fox

iTrader: (3)

If you need any clarification, I have a print copy as well.

bliffle

Manana.

I just sold my REPU to a young guy from Berkeley. Hated to let it go, but I'm just not using it.

Now if I can just sell that pretty 85GSL I have...

I'm worried about the SE because I suspect that the part that's bent is the axle housing flange, which is usually a sheet metal stamping and pressed onto the axle housing, so I have a bigger job than I would like.

Tell me I'm wrong.

bugman1973

you could be wrong. lets hope it doesn't come to buying a new axle shaft.

bliffle

New axle shaft is a big job, maybe, but if the axle housing is damaged, or the flange, then that's a big job too. I'm getting all tuckered out just thinking about it.

I think the caliper mount is like the FC with mounting bolts hidden behind the caliper.

I'll find out when I get back to it after morning errands.

ukcodger

This damage sounds unusual. Thinking about the UK car and assuming the rear calipers are the same, I think you may have hit the caliper on the manhole cover and that has bent the caliper mounting bracket. It is simple to get this bracket off the axle tube - remove the caliper then just two 14mm bolts. You don't have to pull the half shaft to do it.
I doubt the axle tube or half shaft would bend, most likely in my mind they would simply break.
Good Luck

bliffle

Bingo! Problem fixed! Took about 1 hour: no cash expenditure.

Thanks to all you guys, especially Sgt Foxs manual and ukcodgers 14mm bolts.

Loosened up the caliper from the flange (after uselessly pounding on the 3/16" flange forging with a 3lb mall attempting to warp it back) then I pivoted the caliper on the lower mounting bolt and stuck a couple of flat washers in between the caliper and flange at the top fastener, snugged it all down and it works!

I might improve that shim with an additional 1/32", but it's good enough the way it is. However, I'll re-visit this fix when I get a new rotor and pads.

This proves, once again, that guile, research and laziness ( I don't know which is most important) beats brute mechanics every time!

ukcodger

Good news. Sounds like the caliper mounting bracket is bent. I would get a replacement bracket from the wreckers (dismantlers do you guys say?), in order to ensure that everything stays in line and the pads don't wear unevenly.

orion84gsl

iTrader: (5)

We say wreckers, pick-a-part, pick-n-pull, junk yard. Good work bliffle.

bliffle

I'll try to get a bracket, maybe at the PnP, maybe a WTB in the classifieds. I wonder if it's the same on a 12A as an SE, since SEs never show up at the local PnPs? I suppose I could look at one of my 12As to find out.

I'm still not sure exactly where the mount is bent. I'm concerned that the strength of the bracket caused the axle housing to bend, which would mean I'd have to replace that housing as well as the bracket. On the other hand, if the half-shaft and it's flange are not bent then the shim I inserted simply restored the original brake geometry and there's no apparent need to replace the caliper bracket. An alignment shop could tell me for certain, or I can construct an alignment test rig myself using a little laser and some straightedges and maybe a fabbed fitting. That would tell if the bend is in the half-shaft or the housing/bracket. But I suspect that someone in a follow-car could tell me the same thing simply by looking for wheel wobble.

mazdaverx713b

iTrader: (91)

glad to hear you got it fixed!!!! didnt you paint your SE recently? i remember a thread a year or two back with pics of the newly painted car and maybe the car before it was painted.....

bliffle

Yes, I painted it in 2006. Since then I've upgraded some trim items, and generally done some deferred maintenance. If I decide to keep the SE I'll paint it again and have some subtler dings cleaned up. The old paint was so bad I couldn't even see how much I'd have to do, but now I'd like to put a good finish on it.

This SE seems to be very tough and reliable, since I've had it now for 30k miles.

bliffle

Lucky me! An SE showed up at the PnP (San Jose Commercial st. PnP, for you NorCal junkyard hounds) and I got a new wheel with straight rim, rotor, etc, for less than $40.

Cleaned it up and it looks like it'll be just what I need.

If I were younger and had more work space I'd take the whole car, but the ants and termites are already starting to eat away at some parts.

j9fd3s

iTrader: (3)

before you call it fixed, you might wanna put the rear of the car in the air, and let it idle in 1st to see if the axle is bent. the axles are big peices of steel, but ive seen more bent ones than you'd expect (more than i'd expect sometimes too)

if it does need an axle, ive got new and used ones socked away

bliffle

Indeed, I'll do that, but probably next week after I return home.

Seems to me that a guy can take off the wheel and attach a laser beam to the rotor and then rotate it to see if it's square or not.

bliffle

I'll be doing that. I had new tires mounted today and my mechanic pointed out that I'm leaking oil at that wheel, so it needs bearings and seals, at least. So I'll figure to replace those (both sides), at least, hopefully next week.

I think I can check the axle trueness just by hoisting the right rear wheel on a jackstand and rotating the wheel by hand, using a feeler on a stand (or clamped to the fender lip) and eyeballing it.

If I need an axle I'll try the PnP first, then I may call on you for one of your collection. They're quite expensive from Mazdatrix, as one would expect.

I'm also concerned that the axle housing and/or the caliper mounting flange that's fixed to it is warped and may need to be replaced or straightened lest the new bearings/seals start leaking immediately.

I should have grabbed the axle and housing from that PnP car while I had a chance.

What are the chances that I'll have to replace the axle housing? I wonder if I can straighten the caliper mounting flange just by applying a large C-clamp properly with the axle perhaps shimmed out a little. That flange is about 2-3 mm offline.

justint5387

iTrader: (1)

I can sell you my GSL-SE axle housing for $30 if you need one. I live in Fremont, so not that far.

bliffle

Thanks. I'm going to check that axle tonight. I'll be over in Fremont tomorrow, so If I need the housing I can pick it up then.

justint5387

iTrader: (1)

Make sure you come at night, I will be in the SCCA Divisional for Auto-x