Now Be honest..., Rebuilding the transmission.... |
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Now Be honest..., Rebuilding the transmission.... |
aveale |
Oct 19 2005, 08:19 AM
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#1
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Fun Times Group: Members Posts: 194 Joined: 18-August 04 From: Ottawa, Canada Member No.: 2,563 |
Now I don't want the "15 minute Oil Cooler Seal" Replacement Hoax (IMG:http://www.914world.com/bbs2/html/emoticons/wink.gif)
I have a grindy going into second gear and that is it. The gates are tight everywhere, linkage is great, bushings seem fine. How difficult is it to go into the tranny and update some worn bits? As a frame of reference, I have taken the engine out, did some fuel line and injector stuff, oil cooler seals, valve adjustments, exhaust and heating stuff...minor yet somewhat brave for a newbie. I have no problems spending cash, but I would love to give this a go if it is do-able. Please help me decide --> is it something I should do or farm out??? Cheers T |
jr91472 |
Oct 19 2005, 08:29 AM
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#2
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"I'm pacing myself sergeant..." Group: Members Posts: 1,205 Joined: 2-August 04 From: McKinney, TX Member No.: 2,437 |
Very doable as long as you do the research and prepare. I used the bondo's thread in the Classics section and Red-Beard's article (see his website) as a guide.
Get a gear puller or similar press for getting the pinion and drive shafts out of the intermediate plate (I didn't like the (IMG:http://www.914world.com/bbs2/html/emoticons/smash.gif) technique....but to each his own). That is not to say, however, that you won't find other problems once you get in there. For example, one of my intermediate plate bearing fell apart once the pinion shaft was removed. I wasn't exactly expecting that.......but then again it was a 30 year old gear box. The whole process was really cool (IMG:http://www.914world.com/bbs2/html/emoticons/aktion035.gif) good luck and enjoy! |
Dave_Darling |
Oct 19 2005, 08:33 AM
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#3
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914 Idiot Group: Members Posts: 14,991 Joined: 9-January 03 From: Silicon Valley / Kailua-Kona Member No.: 121 Region Association: Northern California |
Read red-beard's transmission rebuild article. Seems reasonably straight-forward, but the "while you're in there" parts add up in a huge hurry!
http://home.san.rr.com/pb914/rebuild/ --DD |
Demick |
Oct 19 2005, 08:44 AM
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#4
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Ernie made me do it! Group: Benefactors Posts: 2,312 Joined: 6-February 03 From: Pleasanton, CA Member No.: 257 |
I agree that Red-Beard's article is excellent. Haynes is also pretty good with the exception of being very vague on setting the shift fork alignments.
One exception to Red-Beard's article though - I would never attempt to do this with the transmission in the car. Remove the transmission first. There are too many potential pitfalls if you don't. Besides, you probably wanted to replace the mainshaft seal anyway. Demick |
Matt Monson |
Oct 19 2005, 08:45 AM
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#5
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Member Group: Members Posts: 156 Joined: 9-August 05 From: Boulder, CO Member No.: 4,562 Region Association: Rocky Mountains |
Parts do add up in a hurry if they are bad. All 6 bearings will cost close to a grand to replace, but it is rare that more than 3 or 4 of them will need it. But there really isn't much risk in going in there and trying it yourself. If your tranny is totally bagged out, our shop always has rebuilt 914 boxes on the shelf at $1850 w/exchange. If you get in there and there is way too much wrong, you can still send us your core in pieces for exchange. Or, good used boxes are always around on E-bay, here in the classifieds, and places like Parts Heaven for substantially less $$$. So, go for it...
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Joe Ricard |
Oct 19 2005, 08:46 AM
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#6
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CUMONIWANNARACEU Group: Members Posts: 6,811 Joined: 5-January 03 From: Gautier, MS Member No.: 92 |
Out of the 3 transmissins I pulled apart one one had both intermediate bearings in useable shape.
2nd gear requires whole gear stack to come out. remember the number of paper shims/gaskets between the intermidiate plate and case. DON'T TAKE OUT RING GEAR. you only have a 50/50 shot at getting it back in the right direction. (IMG:http://www.914world.com/bbs2/html/emoticons/rolleyes.gif) |
Demick |
Oct 19 2005, 08:51 AM
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#7
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Ernie made me do it! Group: Benefactors Posts: 2,312 Joined: 6-February 03 From: Pleasanton, CA Member No.: 257 |
BTW. If you grind going into second, then you have worn the dog teeth. If you just replace the synchro band, your grinding will go away, but you will probably end up with much difficulty getting into second instead. So you probably need to replace the dog teeth and slider for 2nd gear as well. Best thing to do is replace your 2nd/3rd slider with a good 4th/5th slider from a donor transmission as the sliders are big $$. And since your 2nd/3rd gearstack is already apart - definitely replace the 3rd gear synchro as well. I assume you are already doing the 1st gear stuff as that wears the most.
Demick |
jimkelly |
Oct 19 2005, 09:11 AM
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#8
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Delaware USA Group: Members Posts: 4,969 Joined: 5-August 04 From: Delaware, USA Member No.: 2,460 Region Association: MidAtlantic Region |
According to Red Beards article - "All Dogteeth are the same for all gears. All Synchro bands are the same for all gears. So, why do 1st gear dogteeth cost less in the catalog? The dogteeth come with brake bands, the little guys that sit under the circlip. 2nd-5th gears need to be synchronized in both directions (Spinning the gear faster and spinning the gear slower – i.e. up-shifting and downshifting)."
I this accurate - are all dog teeth and syncros are the same ? Also 5th would not need to be syncronized for up shift - just like 1st not need to sync for downshift - so neither would need two brake bands? Jim |
bondo |
Oct 19 2005, 09:19 AM
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#9
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Practicing my perpendicular parking Group: Members Posts: 4,277 Joined: 19-April 03 From: Los Osos, CA Member No.: 587 Region Association: Central California |
No, the notches in the first gear dog teeth are different, to accomodate the different bits that go inside. You can use 2nd-5th gear dog teeth, but you have to use the 2nd-5th gear bits that go inside, so you lose the engineered "eaiser to engage 1st from a stop" which isn't all that bad considering the money you can save. The syncro bands themselves are the same though. (shameless plug: I have good used dog teeth for sale) (IMG:http://www.914world.com/bbs2/html/emoticons/biggrin.gif) |
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olav |
Oct 19 2005, 09:20 AM
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#10
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Senior Member Group: Retired Members Posts: 1,107 Joined: 28-December 02 From: Los Gatos, CA. USA Member No.: 34 Region Association: None |
I just did it two weeks ago. Replace my 1st and 2nd gear synchros. My dogs teeth etc. were still in great shape as I caught it early. I have useless pics on my blog.
Took the tranny out Friday night put it back in Saturday all fixed up. |
Joe Ricard |
Oct 19 2005, 09:25 AM
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#11
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CUMONIWANNARACEU Group: Members Posts: 6,811 Joined: 5-January 03 From: Gautier, MS Member No.: 92 |
Not exactly. 1st gear slider and dog teeth is different. and only has 1 brake band. all other gears are the same dog teeth sliders wise. all synchro bands are the same. Reverse is only one not synchronized. I was playing around this morning driving to work. rolling to stop and selecting 1st while car is still rolling. went in every time. Once stopped and clutch is let out and then pushed in when light turns green I just give it half a second and slide in gear easy. goes in most everytime. sometimes drags or feels like it is binding. But just do the 2nd to 1st thing and all is good. (sorry just rambling). |
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aveale |
Oct 19 2005, 09:59 AM
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#12
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Fun Times Group: Members Posts: 194 Joined: 18-August 04 From: Ottawa, Canada Member No.: 2,563 |
Sounds good family,
I guess if I screw up, I can always throw money at it! Please stay tuned for any questions/queries/nightmares! T |
jimkelly |
Oct 19 2005, 10:10 AM
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#13
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Delaware USA Group: Members Posts: 4,969 Joined: 5-August 04 From: Delaware, USA Member No.: 2,460 Region Association: MidAtlantic Region |
sorry for semi hijack.
when it is said "engineered "eaiser to engage 1st from a stop" with proper 1st gear bits - what does this mean? Is it harder to locate 1st or what - and would using 2/3 or 4/5 dogteeth etc cause premature wear? Jim |
bondo |
Oct 19 2005, 10:37 AM
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#14
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Practicing my perpendicular parking Group: Members Posts: 4,277 Joined: 19-April 03 From: Los Osos, CA Member No.: 587 Region Association: Central California |
In the factory manual it describes how it works.. but basically, first gear is the only one that needs to engage when everything in the trans is stopped. Instead of having the bits on one side of the dog teeth that help upshifting, (since you can't upshift into 1st) it has different bits that help engagement when stopped. I think it's a pretty minimal effect, considering how many times I've tried to start in third, which doesn't have the special bits but is just as easy to shift into when stopped. It won't affect "locating" first, it just makes it engage easier. Basically what happens is the teeth of the dog teeth need to engage into the teeth of the slider. If the teeth line up point to point, exactly, it won't go in. I wouldn't suggest using 2nd-5th dog teeth in first unless the dog teeth and slider points are sharp, as the more dull they are, the wider the point becomes and the greater the chance of first not engaging. I don't see how it could cause extra wear, except maybe a little from occasionally having to shift into another gear before going into first if it doesn't want to go into first. That probably wouldn't happen very often though. |
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Mark Henry |
Oct 19 2005, 11:00 AM
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#15
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that's what I do! Group: Members Posts: 20,065 Joined: 27-December 02 From: Port Hope, Ontario Member No.: 26 Region Association: Canada |
I have a guy in Toronto who rebuilds them for me, he's been doing Porsche tranny's for 20+years.
I had one (built out of 2 cores, a few new parts and seals) done this year for a customer ..cost me $1800 Canadian. |
John |
Oct 19 2005, 11:11 AM
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#16
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member? what's a member? Group: Members Posts: 3,393 Joined: 30-January 04 From: Evansville, IN (SIRPCA) Member No.: 1,615 Region Association: None |
That's what I thought until one windy day in Michigan at Grattan Race Track about 14 years ago. An instructor wanted to drive the car and my dad let him. (last time someone other than my father or I have driven the car) Anyway, he missed a shift and went from 5th to 2ond instead of 5th to 4th. He was used to his old worn out 914-6 sloppy tailshift trans and not our tight bushed sideshifter. Needlesss to say, the shift forks moved during his violent flailing. I had to re-adjust the shift forks. I was loading up the car when a local 914 (expert) Bob Shedd came along and asked what was up. I explained what happened and he suggested pulling the tail off the trans right there in the paddock. Unsure of how this was going to turn out without my nice clean shop, I hesitantly did what he was telling me to do. (I had rebuilt a gearbox befor this, but only in my nice clean shop) Everything went fairly well and everything went well. The hardest part was getting the splines on the input shaft to line up with the clutch disc. Another nerve wracking item was the washer for the 1st/reverse bearings in the tail piece. It went well and I COULD do it again, but would rather not. So I know it CAN be done at the track in the dirt. The tranny is not that difficult to work on. Just be clean, organized and take your time. Good luck |
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davep |
Oct 19 2005, 11:31 AM
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#17
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914 Historian Group: Benefactors Posts: 5,152 Joined: 13-October 03 From: Burford, ON, N0E 1A0 Member No.: 1,244 Region Association: Canada |
I would seriously consider getting a good used tranny and rebuilding that while keeping yours in reserve.
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jimkelly |
Oct 19 2005, 12:09 PM
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#18
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Delaware USA Group: Members Posts: 4,969 Joined: 5-August 04 From: Delaware, USA Member No.: 2,460 Region Association: MidAtlantic Region |
I don't know what - Dr. Evil's (Mike) - schedule is like but he is located in PA (east cost) and rebuilds 914 trannys for about $500 labor + plus parts. My uinderstanding is he'll even help locate used parts but this would take longer. Jim
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aveale |
Oct 19 2005, 12:41 PM
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#19
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Fun Times Group: Members Posts: 194 Joined: 18-August 04 From: Ottawa, Canada Member No.: 2,563 |
Did you mean getting a used one and keeping mine in "REVERSE"? Ha Ha Ha Thanx all for the food for thought! T |
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