Back axle issue
#1
Senior Member
Thread Starter
Back axle issue
When I tighten up the lugs on the back wheels the hubs lockup. It appears that the rims of the drums are making contact with the backing plates. Any ideas?
Herb
Herb
#3
ancient wizard...
Lug bolts right? Are they original, original wheel(s)? Are brake drum/backing plate original? Are backing plates bent? Brake shoes replaced,compare with old,same width? Do you have retainer screws for drum installed & can you turn drums both sides with out wheels installed? I know,20 questions...
#4
Senior Member
Thread Starter
Lug bolts right? Are they original, original wheel(s)? Are brake drum/backing plate original? Are backing plates bent? Brake shoes replaced,compare with old,same width? Do you have retainer screws for drum installed & can you turn drums both sides with out wheels installed? I know,20 questions...
Herb
#5
ancient wizard...
Putting just drums on with retainer screws should be able to duplicate the problem without wheels being in the way-installing wheels won't change drum installed depth. Is there any rust in the machined area of the drums that seat on axle to prevent drum from seating squarely on axle ? Has rear differential been out of car sitting on ground with weight on backing plates possibly bending/distorting them ? Have axles been out of housing(to replace bearings?) and maybe got distorted somehow when bearings pressed off/on?
#6
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Original wheels, drums, and lug bolts. When the brakes and wheels are removed the hubs spin fine. I installed just the drums (no shoes or other brake parts) and bolted on the wheels and the drums seem to be dragging on the backing plates. Could the hubs be in too far?
Herb
Herb
as you recall, its axle, backing plate, bearing spacer, bearing and then retaining collar.
axles are the same on both sides, so it can't be that.
there are a couple of different drums, did those get replaced?
#7
ancient wizard...
Try putting just drums on with retainer screws to duplicate problem. With wheels out of the
way may be easier to see what is going on. Wheels installed will not change installed brake drum axle
relationship. Has differential been out of car,on ground,with weight on backing plates possibly bending them? Have axles been out of housing(to replace bearings?). Possible backing plates got distorted during pressing off/on axle bearings. Pretty certain there's a spacer that goes under bearing when put on axle with a collar on the other side of bearing,was that reinstalled if bearings were replaced?
Other than distorted backing plates,a missing spacer is only thing i can think of that would
change axle depth dimension causing a serious interference fit with drum & backing plate.
way may be easier to see what is going on. Wheels installed will not change installed brake drum axle
relationship. Has differential been out of car,on ground,with weight on backing plates possibly bending them? Have axles been out of housing(to replace bearings?). Possible backing plates got distorted during pressing off/on axle bearings. Pretty certain there's a spacer that goes under bearing when put on axle with a collar on the other side of bearing,was that reinstalled if bearings were replaced?
Other than distorted backing plates,a missing spacer is only thing i can think of that would
change axle depth dimension causing a serious interference fit with drum & backing plate.
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#9
Waffles - hmmm good
iTrader: (1)
Make sure you have the right drums. The SA drums have a slot machined around the edges that fits over the
backing plates to kind of seal up the assembly. If you got new drums they may be FB ones which don't
have this slot and so they will not fit on the SA backing plate.
Take a look at rockauto, 81-85 have a different part number from 79-80.
backing plates to kind of seal up the assembly. If you got new drums they may be FB ones which don't
have this slot and so they will not fit on the SA backing plate.
Take a look at rockauto, 81-85 have a different part number from 79-80.
Last edited by t_g_farrell; 06-19-17 at 08:55 AM.
#10
1st-Class Engine Janitor
iTrader: (15)
Make sure you have the right drums. The SA drums have a slot machined around the edges that fits over the
backing plates to kind of seal up the assembly. If you got new drums they may be FB ones which don't
have this slot and so they will not fit on the SA backing plate.
Take a look at rockauto, 81-85 have a different part number from 79-80.
backing plates to kind of seal up the assembly. If you got new drums they may be FB ones which don't
have this slot and so they will not fit on the SA backing plate.
Take a look at rockauto, 81-85 have a different part number from 79-80.
Pretty sure I posted pictures about this oh, 7 years or so ago... heh.
UPDATE: Searched - -yep:
https://www.rx7club.com/1st-generati...brakes-787270/
Last edited by DivinDriver; 06-23-17 at 02:02 PM.
#11
Senior Member
Thread Starter
The problem was missing spacers. Got a new set from Mazda, new bearings from autozone and paid the same machine shop 40 bucks to remove and install correctly this time. Thanks for the help. Herb