 Trans gear flip. Can I do it? |
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| Han Solo |
 Dec 27 2015, 01:45 PM
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Member  Group: Members Posts: 291 Joined: 30-September 13 From: Middle Tennessee Member No.: 16,456 Region Association: South East States  |
I'll probably get more eyes on the thread in the Garage.
I've got a spare 901 trans purchased about 2 years ago. No idea how many miles are on it or what year car it came off of. What I do know is I need a different gear set for my Prepared '73 914 autocross car. I've read through the gear set charts and I believe the flipped 3rd and 5th will get me where I need to go. So today I got that trans on the bench, drained the fluid and removed the rear cover. Those of you who know what they're looking at, please let me know how 1st gear slider and dog teeth look in the photos. My initial observations are that those look pretty good. I noted that someone had installed a magnetic drain plug. That had done it's job and there was about 1/2" of metallic goo stuck around the inside of the plug. The gear oil came out pretty clean with only very slight traces of micro particles. I just read Bondo's thread on trans disassembly and it's pretty intense. There's also no mention of the 3rd and 5th gear flip so I've got no clue exactly what that procedure is. 914 transmission disassembly (IMG:http://www.914world.com/bbs2/uploads_offsite/i1336.photobucket.com-16456-1451245548.1.jpg) (IMG:http://www.914world.com/bbs2/uploads_offsite/i1336.photobucket.com-16456-1451245548.2.jpg) (IMG:http://www.914world.com/bbs2/uploads_offsite/i1336.photobucket.com-16456-1451245548.3.jpg) (IMG:http://www.914world.com/bbs2/uploads_offsite/i1336.photobucket.com-16456-1451245548.4.jpg) (IMG:http://www.914world.com/bbs2/uploads_offsite/i1336.photobucket.com-16456-1451245549.5.jpg) (IMG:http://www.914world.com/bbs2/uploads_offsite/i1336.photobucket.com-16456-1451245549.6.jpg) (IMG:http://www.914world.com/bbs2/uploads_offsite/i1336.photobucket.com-16456-1451245549.7.jpg) |
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| Han Solo |
Jan 1 2016, 07:55 PM
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Member Group: Members Posts: 291 Joined: 30-September 13 From: Middle Tennessee Member No.: 16,456 Region Association: South East States |
Okay. I went in deep today and here's what I found...
Instead of digging deeper into the spare trans that I pulled the cover and 1st gear, I went into another off a '76 parts car, figuring if I monkeyed that up, it wouldn't rally matter. Well surprise, surprise. The dirty trans with a welded rear cover (suspension mount cracked) has what appears to be really fresh syncros, nice sliders and really good dog teeth! I guess when the mount broke, the PO had the trans re-built. Finding that, I'm thinking this is the stack I want to use in the race car. So I pulled the shift rod, wiggled out the intermediate plate and pulled the shift forks with rods. I found out why Red Beard recommends loosening the 30mm nut and castle nut before pulling the intermediate plate (harder to do with the plate out) but I purchased some handy tools a couple days ago from a Porsche shop going out of business - an alignment jig and a spanner with a 1st gear slider welded on it. Once I locked down the stacks, those tools enabled me to get the drive shaft out but the pinion shaft was more difficult. My gear puller wouldn't fit so I had a buddy drive the shaft end out with a large brass punch. Amazingly the bearings remained in good shape. Then to get the other end of the pinion shaft dis-assembled, I used a friction plate with a nut welded to it to hold the input shaft end while I used a large open end wrench on the retaining nut. So I've got everything loose and lined up in order on the bench and I'm taking a real close look at swopping 3rd and 5th gears when I realize that to do that, yes, you do have to flip the gears (to get the correct orientation) also AND that means reversing the dog teeth. Someone let me know if there's something I'm missing here. So, with the dog teeth, sliders and syncros looking so good on these gears, there's no way I'm going to trash the dog teeth and buy another set. At this point, I'm just going to re-assemble this stack (OEM gearing) and probably stick it in the spare case and use the spare end cap. OR... I could use this stack in the case that's in the race car right now and not even have to pull the trans out. (IMG:http://www.914world.com/bbs2/uploads_offsite/i1336.photobucket.com-16456-1451699738.1.jpg) (IMG:http://www.914world.com/bbs2/uploads_offsite/i1336.photobucket.com-16456-1451699738.2.jpg) (IMG:http://www.914world.com/bbs2/uploads_offsite/i1336.photobucket.com-16456-1451699738.3.jpg) (IMG:http://www.914world.com/bbs2/uploads_offsite/i1336.photobucket.com-16456-1451699738.4.jpg) (IMG:http://www.914world.com/bbs2/uploads_offsite/i1336.photobucket.com-16456-1451699739.5.jpg) (IMG:http://www.914world.com/bbs2/uploads_offsite/i1336.photobucket.com-16456-1451699739.6.jpg) (IMG:http://www.914world.com/bbs2/uploads_offsite/i1336.photobucket.com-16456-1451699739.7.jpg) (IMG:http://www.914world.com/bbs2/uploads_offsite/i1336.photobucket.com-16456-1451699739.8.jpg) (IMG:http://www.914world.com/bbs2/uploads_offsite/i1336.photobucket.com-16456-1451699739.9.jpg) (IMG:http://www.914world.com/bbs2/uploads_offsite/i1336.photobucket.com-16456-1451699740.10.jpg) (IMG:http://www.914world.com/bbs2/uploads_offsite/i1336.photobucket.com-16456-1451699740.11.jpg) |
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Posts in this topic
Han Solo Trans gear flip. Can I do it? Dec 27 2015, 01:45 PM
jimkelly I think slider (the side shown, anyway) is usable
... Dec 27 2015, 02:09 PM r_towle Too hard to see for a decent opinion.
For the fli... Dec 27 2015, 03:42 PM
Han Solo
So, take the fifth gears off.
Take the 4th and 3... Dec 27 2015, 08:57 PM r_towle
So, take the fifth gears off.
Take the 4th and ... Dec 27 2015, 11:09 PM 396 Dog teeth and syncro band looks like it past its l... Dec 27 2015, 06:21 PM Han Solo
Dog teeth and syncro band looks like it past its ... Dec 27 2015, 09:04 PM Bleyseng I did the flipping years ago for AX and it was bar... Dec 28 2015, 07:25 AM oldie914 You should not put the gear stack from the 2nd tra... Jan 2 2016, 05:16 AM Han Solo
You should not put the gear stack from the 2nd tr... Jan 2 2016, 06:40 AM oldie914 The gear cluster on the intermediate plate, ring/p... Jan 2 2016, 07:47 AM Han Solo
The gear cluster on the intermediate plate, ring/... Jan 3 2016, 06:31 PM J P Stein That trans is in pain.
The keys to a good shifting... Jan 2 2016, 07:52 AM sixaddict Since there seems to be some knowledgeable subscri... Jan 2 2016, 08:07 AM J P Stein
Since there seems to be some knowledgeable subscr... Jan 2 2016, 08:54 AM r_towle
Since there seems to be some knowledgeable subscr... Jan 2 2016, 08:15 PM wndsrfr
Get another fifth gear and put it back in as fif... Jan 2 2016, 08:51 PM jmill
I am running out of rpms at top end on tracks wit... Jan 2 2016, 10:51 AM Dave_Darling That's the easiest way to go.
You can make ta... Jan 2 2016, 07:43 PM Van914 With a 3.0 stock gears are the way to go. Jan 3 2016, 07:32 AM sixaddict Thanks for the gear input ....Couple of good thoug... Jan 3 2016, 09:25 AM |
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