Where did you source the bearing/gasket kit for the trans? I'm about to start my first attempt at a trans rebuild for my FB style 12A trans.
Where did you source the bearing/gasket kit for the trans? I'm about to start my first attempt at a trans rebuild for my FB style 12A trans.
sevenracer said:Where did you source the bearing/gasket kit for the trans? I'm about to start my first attempt at a trans rebuild for my FB style 12A trans.
https://www.ebay.com/itm/Mazda-5-Speed-Transmission-Bearing-Kit-1981-92-15mm/220657263919
Company name is Transparts Warehouse. I did not buy synchros because it shifted fine.
Drivetrain.com was where I was originally going to buy from.
It appears that the main difference between FB and FC is that some FC transmissions have synchronized reverse. Not sure what the difference is between 15mm and 20.5mm front countershaft bearing, as far as what models got what.
SA transmissions had 30 tooth synchros, not 36. IIRC the SA type trans internals extended into the 1981 or 1982 model year.
Cool, thanks. That's definitely better pricing than Mazda motorsports. I ordered a bunch of parts from them including synchro's but missed a couple of the bearings I need.
That looked like a fun course
Alignment was quite a bit wonky for the drive home, and there was a marked increase in horrible vibrations. I figured that I'd probably knocked the rrarend out of square. Fortunately, there was no shortage of trucks driving 55-60mph on the Turnpike for me to follow. Also noted that the bearing noises got quieter if I applied the handbrake. Failing axle bearings?
Today, on the alignment rack.
That's not horrid. I've no idea what happened. But, clearly, that positive camber on the left front has got to go. I was really feeling it on the "bumpy concrete" inner course at the track.
Also noted this.
Berking exhaust systems....
Chugging right along... Five new M8x20 bolts. There is no torque spec I could find, so I used serrated washers, Loctite, and 45 ft-lb.
Oh, this is where all the metal was coming from. When the mainshaft was walking, it was grinding 1st gear into the bearing plate. Note that there is room for the retainer plate bolts to be 30mm or more long. Stock is like 16mm!
it was at this point that I regretted not disassembling the shift rods. I have an idea for how to assemble the next one.
When you install roll pins, always put the seam in line with the direction of force.
I left the roll pin out of the 5-R fork until torquing the nut, so I could have it locked in two gears.
And here we are. Not have to dig back to the disassembly pics so I can put this Jenga mess together in the correct order.
Ok, Reverse and spacer go on countershaft, then 5th driven goes on mainshaft, then 5th drive, bearing, and nut go on countershaft. Then on the mainshaft, locator ball goes in hole while hardened spacer waits in the wings.
Then spacer goes on.
Then thickness adjusting shims and their retainer collar. These had a definite wear pattern, I turned them around backwards to tighten the spacing back to OE.
Then bearing gets tapped on. No press needed.
Adjustment shims on this side too, again rotated to wear on a different part of the shim on each side.
Then another hardened spacer, and a beefy circlip. Not the flimsy ones that retain the speedo drive gear.
Endplay clearance is ideally .004", or .1mm. I'm at .011", which is a lot better than the .035"+ that I have seen.
Do a couple more things and then you have this:
Most important part!
Now no wondering WTF transmission is what.
One down, five or six to go.
In reply to Pete. (l33t FS) :
Hey that looks like the really clean version of what I just loaded into the back of a Subaru. No refunds once it's loaded.
Snowmageddon happened (we got like 12-14 inches overnight) and I still had my ECSs on.
Bad idea. Do not recommend.
for instance, going up the just-plowed driveway at work involved a 100' long, 2nd gear redline AWD burnout to go walking speed. Stopping was even more fun.
What tirespin on cold tires looks like.
Now we are in winter mode. It feels just so UNFAIR.
Of course, day 2 of Snowmageddon did not happen, so shoveling the driveway meant the leftovers melted the next day. Cleveland has not salted the roads, and everything re-froze last night, including the rivers of snowmelt.
SOOOOO CLOSE
Pulled apart the black "rebuilt" trans. More like "needs rebuilt".
very rusty inside...
#2 synchro splines are pretty worn
And the center bearings are wiped out. There is no longer a cage in the countershaft bearing, it's just loose balls. Very loose.
5th gear is held on with a circlip, not a nut. 5th driven gear has 15 teeth. The 5-R slider is also phenomenally worn.
Interestingly, the gearset does NOT have the lash damper thingy on the countershaft driven gear.
Stampie (FS) said:In reply to Pete. (l33t FS) :
Hey that looks like the really clean version of what I just loaded into the back of a Subaru. No refunds once it's loaded.
As it turns out, with careful packaging, one can fit four mounted 235/45R17s and one Mazda transmission in the back of an S60R.
Still can't go to Patrick's without driving right past it and going "Oh, crap, THAT's where it is"
That transmission is, oddly rusty. I've had three apart and never seen that. It's interesting that they all seem to be just a little different. More/less circlips, straight/helical reverse, sealed/unsealed bearings, washers/no washers under spring caps, harmonic balancers/no balancers, etc. Do you rebuild your own? I've done it twice. The first time was little more than pull apart, inspect and reassembly but the second time I made sure all the clearances were in spec and replaced every bearing. Still kicking myself for not replacing the synchros though. Getting new shims, spacers, roll pins, etc. was a major pain though.
In reply to infernosg :
That kind of rusty in a gearbox happens in storage, either from condensation, or someone kept it tail shaft up where a roof leak got it. Less commonly it came from a flood car.
In reply to Pete. (l33t FS) :
That transmission is the 2nd of the two free ones Seth offered a few years ago. You know the ones I beat you to then had no use for them. You got one of them two Challenges ago.
In reply to infernosg :
It was one of the transmissions that came with the car from Alabama, and HE had got it from someone else. I assume humidity played a large role.
Also, if it got hot enough to melt the plastic bearing cage, who knows what its history was.
The trans upthread was my first rebuild. I used to chuck 'em when they developed a lot of endplay (or just plain broke, or got noisy) because it was easy to find replacements for $200 within a hundred mile junkyard radius. Now it's mail ordering a trans from halfway across the country for $500 plus shipping.
Going to play closer attention to fluid quality, and clutch disengagement from now on! Am thinking of rigging a fluid pump/filter arrangement for the black car. Red car runs in a very limited prep class so that is not an option.
In reply to Pete. (l33t FS) :
Yeah, $400-500 seems to be the going rate now. I guess supply is drying up now that Mazda hasn't used these in a production model in what, 15 years? Who knows how long spare parts will last. The last time I rebuilt mine I stocked up on one of every size spacer just so I would have them for the future. Fortunately rebuilding them isn't too hard. One of these years I need to make my own super-deep socket for the 5/R clutch hub but instead of borrowing/renting one. That's the worst part of the process for me.
I've thought about rigging up a transmission cooler as well. I'm still not exactly sure what causes these to break. I've seen teeth sheared off gears and twisted output shafts due to too much power but I've also seen cracked cases behind Spec Miatas and IT RX7s. Not sure if that's a temperature thing or what. Historically, I've always run Redline MT90. Just this last year I switched to Ford XT-M5-QS to see what all the Miata guys were raving about. Can't say I've noticed a big difference. It's maybe a little smoother at colder temperatures.
In reply to infernosg :
I've blown 2nd gear, 3rd gear, and the input gear. Most of the time, I would change them out when they would start racking excessively or shuddering in 5th gear beyond what I will tolerate. I now am pretty confident that the racking is those bolts loosening up, and the shudder is excessive endplay. Thus my use of longer bolts torqued to "all of the torque", with Loctite and lock washers. I will be using serrated head bolts from now on, too.
Technically they have not made this transmission since 1983. According to https://web.archive.org/web/20051101225021/http://members.ij.net/mrmazda/tranchrt.txt the 15 tooth 5th was last used in '83.
I should probably look into B2200 transmissions since they also had the 3.6/2.2 1st/2nd that I like. They MAY have an extended pinion like the Miatas, which would require machining about 5/8" off the end. Which requires complete disassembly of the trans.
Making O-rings by heaterlight.
Did you tear apart your bicycle or is that a different one?
The wheels and saddle have to be removed to fit in the trunk. Barely fits, have to fold the rear derailleur back to get it past the trunk opening.
Bike may be getting a garage mate. Another one of those "omg can't believe this is for sale" details.
Moment of clarity. I should not spend $3500 on a brand new '95 Litespeed mountain bike, when that would buy an MS3-Pro unit, and a Gripper differential, and a lightweight flywheel, and a set of ID injectors, for the Quantum.
Speaking of future expenditures.
Assembly of the 12A for the '81 ground to a halt because I realized that I did not buy oil control O-rings.
While I am here, I may as well document all the other things that I forgot to buy.
For the engine, I still need.
Intake gasket set. Ordered, Atkins
Front cover and water pump housing gaskets. Ordered, Atkins
Water pump.
Carburetor rebuild kit (yes, I am definitely keeping the Nikki, that's the whole point!)
Genuine Mazda oil control O-rings. Ordered, Atkins
MAYBE new Mazda rings. Need to go into my stash of useds and see how many good ones I can dig up. No need
For the car:
Dig into the turn signal flasher unit and try to repair it.
WIndshield trim clips.
Try to find a windshield trim top center piece.
A modern yet 2-post stereo would be nice.
Replacing the heater core would be nice, but that can wait until summer and I can work with both doors open.
Properly repair the fuel pump system: this entails locating a fuel pump mounting plate, instead of screwing the pump directly to the floor. This makes an enormous difference in NVH.
Locate turn signal housings in the great piles o' stuff acquired with the car and install
Trailer hitch and wiring
TRY to locate black '79-83 seats
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