Gearbox Gurus: How bad did I fark things up?
#1
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Gearbox Gurus: How bad did I fark things up?
So, first things first: I’m an idiot and didn’t recognize the obvious warning signs of a slowly failing clutch master cylinder and dragging clutch. And then I doubled down on the idiocy by not fixing the problems right away when I recognized them. I have replaced the offending parts and the underlying issue should be fixed.
My car is an S1 but the gearbox is an S2 so... here we are.
The gearbox grinds and simply wont go into 2nd at >5k rpm. I sourced a $400 S1 gearbox to keep the car on the road while I embark on a project to learn how manual transmissions work while repairing this one. I’m not doing this to save money since that’s usually a fools errand for bumblefarks like me.
Notice how the dog teeth to the left of the 2nd gear synchro are different shape from the rest of the gears? I’m thinking this is a problem. So, it’s 2nd gear as well as it’s synchro that need replacing, yes? Any recommendations regarding the rest?
1st gear
2nd gear
5th gear
6th
My car is an S1 but the gearbox is an S2 so... here we are.
The gearbox grinds and simply wont go into 2nd at >5k rpm. I sourced a $400 S1 gearbox to keep the car on the road while I embark on a project to learn how manual transmissions work while repairing this one. I’m not doing this to save money since that’s usually a fools errand for bumblefarks like me.
Notice how the dog teeth to the left of the 2nd gear synchro are different shape from the rest of the gears? I’m thinking this is a problem. So, it’s 2nd gear as well as it’s synchro that need replacing, yes? Any recommendations regarding the rest?
1st gear
2nd gear
5th gear
6th
#2
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Update:
Internet randos on Reddit say that the differently shaped dog teeth for 2nd gear are normal. This is done because the 1-2 shift has the highest different in angular velocity and this shape sacrifices ease of release for ease of insertion.
So, unless I find anything really scary when I take everything apart this weekend, it'll just be a set of synchros.
Internet randos on Reddit say that the differently shaped dog teeth for 2nd gear are normal. This is done because the 1-2 shift has the highest different in angular velocity and this shape sacrifices ease of release for ease of insertion.
So, unless I find anything really scary when I take everything apart this weekend, it'll just be a set of synchros.
The following 2 users liked this post by Steve Dallas:
blu3dragon (03-22-2019),
Mr. Pockets (09-17-2018)
#5
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Just in case anyone was wondering what a mostly disassembled S2 gearbox looks like...
Going to do some measurements and get started with a parts list in the next couple of days.
Going to do some measurements and get started with a parts list in the next couple of days.
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blu3dragon (03-22-2019)
#6
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Looks like you got some work ahead of you. I have no clue how it works haha
#7
Smoking turbo yay
I still have some parts of the broken 5th gear sitting in a box. Messed up a shift and destroyed the synchro.
I can take some pictures later.
I can take some pictures later.
#9
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Thanks.
It's effectively broken for my needs so I can't really break it worse than it already is. Besides, if it ain't broke, you're not trying hard enough! (alternately, if it ain't broke, fix it 'til it is)
The disassembly so far has actually been relatively easy. Easier than R&R'ing my engine. The hard part is finding ways around not having a few SST's. One was replaced by a Hazard Fraught 24" adjustable wrench (to remove a 55mm nut on the main shaft). Since I have to torque that nut back down, I'm going to cut the handle off and weld a 17mm nut onto the head so I can use a torque wrench.
It's effectively broken for my needs so I can't really break it worse than it already is. Besides, if it ain't broke, you're not trying hard enough! (alternately, if it ain't broke, fix it 'til it is)
The disassembly so far has actually been relatively easy. Easier than R&R'ing my engine. The hard part is finding ways around not having a few SST's. One was replaced by a Hazard Fraught 24" adjustable wrench (to remove a 55mm nut on the main shaft). Since I have to torque that nut back down, I'm going to cut the handle off and weld a 17mm nut onto the head so I can use a torque wrench.
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boricua13 (09-07-2018)
#11
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Bah, much more fun to do it the wrong way.
Also, this resolves the issue of socket depth since the main shaft protrudes a fair amount from the nut.
Alsoalso, the SST is a "universal wrench" that looks like a bearing puller but has hex sides for grabbing a nut. This more closely matches the SST than a socket.
Also, this resolves the issue of socket depth since the main shaft protrudes a fair amount from the nut.
Alsoalso, the SST is a "universal wrench" that looks like a bearing puller but has hex sides for grabbing a nut. This more closely matches the SST than a socket.
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boricua13 (09-07-2018)
#12
Smoking turbo yay
So is anything actually wrong with your second gear?
I am asking because just yesterday, I ground it another time. That was the third time I ground my second, and without a hard acceleration at all(only coming out of 1st at 4~5k RPM). Pretty sure my clutch is all the way in as well. Never happened with any other gear, either. I ground my 6th once this year, but I knew that time I didn't push the clutch in all the way. The fluid is only a year old.
I am asking because just yesterday, I ground it another time. That was the third time I ground my second, and without a hard acceleration at all(only coming out of 1st at 4~5k RPM). Pretty sure my clutch is all the way in as well. Never happened with any other gear, either. I ground my 6th once this year, but I knew that time I didn't push the clutch in all the way. The fluid is only a year old.
#13
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2nd gear itself? I don't think so. I haven't made all the measurements yet but it looks fine.
2nd gear synchro? Probably completely shot inside. The synchro rings for all the other gears have a clutch-like friction material on the inside face. I haven't gotten 2nd separated yet to look at the ring.
2nd gear synchro? Probably completely shot inside. The synchro rings for all the other gears have a clutch-like friction material on the inside face. I haven't gotten 2nd separated yet to look at the ring.
#14
Sorry to revive an old thread, but I couldn’t find anything while searching and I’m unable to start a new thread right now, but I’ve got an 09 with some transmission issues. The other night while driving home i shifted into to neutral and it was like 5th or 6th gear was still engaged, even though the shifter would still move from side to side as normal when in neutral, so I pulled over and shut it off and restarted it. Car was back in neutral but with a rattling noise coming from around the transmission area. Reverse and 1st-4th work fine but 5th and 6th won’t engage. The shifter will go into both positions but it’s like it is in neutral, am I going to need a new transmission?
#15
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2nd gear itself? I don't think so. I haven't made all the measurements yet but it looks fine.
2nd gear synchro? Probably completely shot inside. The synchro rings for all the other gears have a clutch-like friction material on the inside face. I haven't gotten 2nd separated yet to look at the ring.
2nd gear synchro? Probably completely shot inside. The synchro rings for all the other gears have a clutch-like friction material on the inside face. I haven't gotten 2nd separated yet to look at the ring.
S2 is definitely easier to attempt with the main case access cover, which the S1 trans doesn’t have.
#16
What am I doing here?
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Sorry to revive an old thread, but I couldn’t find anything while searching and I’m unable to start a new thread right now, but I’ve got an 09 with some transmission issues. The other night while driving home i shifted into to neutral and it was like 5th or 6th gear was still engaged, even though the shifter would still move from side to side as normal when in neutral, so I pulled over and shut it off and restarted it. Car was back in neutral but with a rattling noise coming from around the transmission area. Reverse and 1st-4th work fine but 5th and 6th won’t engage. The shifter will go into both positions but it’s like it is in neutral, am I going to need a new transmission?
https://www.rx8club.com/new-member-forum-197/
Post your issue there.
Shortly after that happened, I sold the car.
I haven't gotten around to getting rid of the box of rusty transmission parts.
#17
[QUOTE=NotAPreppie;4910401]Until you have 10 posts and 30 days on the site, you can only start new threads here:
https://www.rx8club.com/new-member-forum-197/
Post your issue there.
Awesome, thank you
https://www.rx8club.com/new-member-forum-197/
Post your issue there.
Awesome, thank you
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