DNMakinson

iTrader: (3)

I am going to reset pinion bearing preload and put in a new pinion seal before I install new to me Diff.

1) One question I have... Can someone share what the carrier bearing pad to pad measurements is BEFORE preload is set? AFTER setting, it is supposed to be 7.300 to 7.303. I'm curious to know what that measurement is before the strain is induced. Yes, I can get that myself after backing off the preload, but I want to know what is normal / expected.

2) Is there an easy way to test the proper action of the Torsen carrier? Stick a couple of axles in and counter-rotate by hand?

Other questions may be forth-coming.

DNMakinson

iTrader: (3)

Also, I don't see anything in the FSM about sealant on the pinion splines, or loctite on the Pinion Nut. No leak issues? No loosening issue?

sonofthehill

iTrader: (1)

1. I might have the information you seek but it will be scribbled on a piece of wood in my garage somewhere.

2. Yes.

3. There is a pinion seal IIRC.

4. It is a nylok type nut.

DNMakinson

iTrader: (3)

It just concerns me that the preload on my unit was in spec as- found, and after preload was removed. In absence of info, I will simply set it at, or just over the high end.

Really wish Mazda had published the change in measures, rather than the final
measurement. That would have also worked if mics were out of calibration.

DNM

Ted75zcar

iTrader: (2)

While I am by no means an expert, I have successfully set a few of these up. IIRC, the "pre" measurement isn't really a thing. The thread pitch on the adjusters and the way the caps go on is really pretty fixed. The carrier is then positioned left-to-right (or right-to-left) in order to get the appropriate lash and wear, and then the preload is added incrementally from both sides to spec. This way you aren't changing lash when setting preload. Your ability to set the preload is somewhat limited due to the adjuster lock notches on the adjusters.

My 2c

sonofthehill

iTrader: (1)

I found my scribbling in the garage, it doesn't have exactly what you are looking for but it says "2.5 notches total preload both sides" if that is any help. My diff is quiet and seems to hold up to pretty hard launches.

DNMakinson

iTrader: (3)

Thanks. that would be correlative information. After we finish, I'll publish both change in dimension and change in notches... for posterity.

DNMakinson

iTrader: (3)

In the end, we did not count notches. We put the measured change in dimension to approximately 0.004”. This had the adjusters within 1 notch of where they were when we took the unit apart. The pinion side was reduced 1 notch to put the backlash at about 0.0038”.

DNM

toso99

Hi, sorry to bring back an old thread, but...
does this mean 1.25 notches each side from the point the bearings are "touching" (like screw the adjusters by hand + 1.25 notch)
English isn't my first language, i hope you can understand 😂

DNMakinson

iTrader: (3)

@sonofthehill See post above. I think toso99's interpretation is correct, but figured I'd get you to answer directly.

sonofthehill

iTrader: (1)

Yes I think that means approximately 1.25 each side. I wrote it a while back, and obviously you need to get the sucker in the right position. Maybe 1.5 on one side and 1 on the other, but 2.5 total. Really you should use a large micrometer and measure the pads.

You guys should know better than to bug me on a Wednesday.

LeoNA

There is some info in the mellens manual. The preload specifications are for new bearings. When I replace pinon seal's I usually mark where the nut is relative to the pinion and then tighten it back to that spot. Usually, it is a bit more preload than it was originally, but nothing like with new bearings. The carrier is the same. As recall the strain on the carrier is substantial, maybe .020" (7.2800" without) and the spec for new bearings is 7.3003-7.3031. With used bearings I go slightly more preload then it was originally. The fore and aft pattern is from the backlash and the pattern difference from the load and coast faces is from the pinion depth.

Mazda MX5 1999-2001 Service Manual (mellens.net)

toso99

@sonofthehill ​​​ Sorry👉👈😂
And thanks a lot
I needed this because my towers are out of spec, they measure more than 7.3031 without any preload and i didn't know what to do
@LeoNA so should I set the carrier preload to let's say 4-5 notches tot?
i lsd swapped my open diff and i used the bearings that came with the lsd, they seemed ok and mostly i forgot to buy new ones so I didn't bother hehe

LeoNA

I have never seen one that was sprung/yeilded. I would double check it with the carrier removed, races and threaded adjusters install with the caps torqued. Make sure you are measuring on the machined pads. If it is out of spec you might consider looking for another case. Any open diff case will work and should be inexpensive.