New Torsen diff re-assembly timing question

[gokart_guy]

I have the newer version Torsen diff (000012 model) with an old version aluminum housing, with the 3 holes connecting the housing to the diff. I had to disassemble the diff gears to drill the the holes in the 000012 cast iron unit, I did mark the element gears relative to each other prior to disassembly, but I did not mark the side (center) gears relative to the element gears. The manual only says that the center gears have to be "coaxial" prior to re-assembly, so I'm assuming the element gears are the only ones that are timed? That it doesn't matter how the center gears are oriented relative to the element gears as long as the element gears are oriented the same way as before relative to each other / the other windows. Is this correct? Would there be a substancial difference in the difficulty to turn the diff shafts if the gear timing were incorrect? I want to be sure before using it after it has been put back together.

Thanks

[gokart_guy]

I have the newer version Torsen diff (000012 model) with an old version aluminum housing, with the 3 holes connecting the housing to the diff. I had to disassemble the diff gears to drill the the holes in the 000012 cast iron unit, I did mark the element gears relative to each other prior to disassembly, but I did not mark the side (center) gears relative to the element gears. The manual only says that the center gears have to be "coaxial" prior to re-assembly, so I'm assuming the element gears are the only ones that are timed? That it doesn't matter how the center gears are oriented relative to the element gears as long as the element gears are oriented the same way as before relative to each other / the other windows. Is this correct? Would there be a substancial difference in the difficulty to turn the diff shafts if the gear timing were incorrect? I want to be sure before using it after it has been put back together.

Thanks

[SNasello]

if i remember correctly, if you dont put the gears back in they way they came out, the diff wont work at all. we have an older torsen diff that this happened too and we cant get it back together properly, its completely locked.

[Boston]

only the element gears matter

[gokart_guy]

That's what I thought, thanks. It seems to spin pretty freely, so I think it is timed right.

[Paul Achard]

Does anyone have a copy of the "M021-DHU University Special information" document? It seems to be the only place containing differential timing instructions, but the link on the torsen site is broken...

Thanks!

[OspreysGoSWOOP]

I'll trade you for the script your school uses to compile the cost report.

I stumbled upon it, bookmarked it for future reference because I thought it was awesome. A few weeks later your team apparently locked down that part of the website to team members only


http://dl.dropbox.com/u/187312...al%20Information.pdf

[Paul Achard]

According to the Torsen FSAE info page, it's the OLD spec sheet that contains the gear timing instructions. When you follow the link "Download a M021DHU General Fact PDF file", unfortunately, you end up on a broken page...

Aren't you a little late for the cost report?

Thanks.

[OspreysGoSWOOP]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Plooba:
According to the Torsen FSAE info page, it's the OLD spec sheet that contains the gear timing instructions. When you follow the link "Download a M021DHU General Fact PDF file", unfortunately, you end up on a broken page...

Aren't you a little late for the cost report?

Thanks. </div></BLOCKQUOTE>

Oh, our cost report went out on time...and it was beautiful. A team member wrote excel VBA code to audit the eBOM and verify we weren't missing any files nor had any extra files. Our eBOM also populates the totals for each item automatically. It was quite enjoyable.


http://dl.dropbox.com/u/187312...Special%20012000.pdf

[Drew Price]

The WayBackMachine (internet archive project) is your friend.


Pull the URL for the old M021-DHU PDF and put it in here: http://wayback.archive.org/web...pecial%20M021DHU.pdf

Then you get this: http://web.archive.org/web/200...pecial%20M021DHU.pdf



<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">"Torsen Traction":

14. What does “timing the differential” mean?

The timing refers to the orientation of the spur gear teeth on the ends of the element gears in relation to the helical teeth. The differential must be timed properly - that is, the gears must be orientated together properly to operate correctly.

15. How do I time the differential?

The timing information is given in the Timing Chart in the lower left-hand corner of the M021-DHU print. Windows 1, 2, and 3 refer to the element gear windows, viewed form the top, in the counterclockwise direction. Install the bottom gears first, around the side gears. Start with each gear’s timing mark straight upward, on the left side of the gear. Rotate the timing mark toward the outside of the differential the number of teeth given in the Timing Chart for each gear. Repeat for the top element gears. When completed successfully, the differential should roll (differentiate) freely.

16. What will happen if the differential is not timed properly?

Proper timing is required for equal load sharing among all the gearing. It is possible to build the differential incorrectly, and have it still roll (with some difficulty). However, the internal loads will not be evenly balanced among the gears, and some will be severely overloaded. This will lead to eventual failure, often catastrophic. </div></BLOCKQUOTE>



The timing marks are tiny tick marks in the root of the spur teeth of the element gears. You will probably have to spend a bit of time cleaning out the spur teeth really carefully to find them in all 6 gears. Then you sit the housing down in front of you, and look at it from the top. Put the lower needle thrust bearing stack into the housing, then the first side gear, then the first round if element gears. As you index each one, slide it's pin into place. Then the 2nd side gear, and upper element gears.

Don't let the assembly turn until you have all 8 of the gears installed, and all the element gears pinned in place, or you have to start over.

Expect it to take a trial or two before you get it.

The two side gears should spin freely in opposite directions when everything is put together correctly.