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benracin
03-21-2004, 09:30 PM
Has anyone tried rebuilding one of these transmissions? I have a transmission I want to use that broke a 3rd gear synchro I think. As far as I can tell and going by the book, I've got to take everything off starting from the drive shaft side taking apart the entire thing in order to get to it. Right now I'm stuck with a large lock nut on the main shaft that you need a 1 1/2 foot deep socket to get out. I looked on mazdamotorsports.com and couldn't find it. If anyone has delt with these things, how did you get that thing off? Unless there's a way to get at the sychros from the other side, but as far as I can tell you'd have to take out both shafts at the same time, and that's not happening unless this lock nut comes off.

The lock nut I believe is holding in 5th gear and is in the 5th gear casing of the transmission. Has my do it yourself strategy hit a road block?

Thanks

Ben
#33 IT7

C. Ludwig
03-21-2004, 11:24 PM
You'll need that socket and real long gear puller. Seems there was a thread on this not too long ago. Buy a socket that fits, cut the ceter out of it so that it slides over the shaft. Weld a length of tube to it and fab a 1/2" square hole to mount it to your favorite impact. For the gear puller just use some thick flat stock to make the jaws.

------------------
Chris Ludwig
08 ITS RX7 CenDiv

planet6racing
03-22-2004, 01:28 AM
Ben:

Just double clutch. You won't need the synchro then!! http://Forum.ImprovedTouring.com/it/wink.gif Plus, it'll make it that much easier for me to get around you!!

Seriously, though, if there's anything I can do to help, give me a call. I have access to things others dream about at work...

------------------
Bill
Planet 6 Racing
bill (at) planet6racing (dot) com

eprodrx7
03-22-2004, 08:46 AM
Well in the book it says that you are suppose to put new nuts on when you put it back together, so you could use a chisel to get it off (hack way) I did close to what Chris did. I made the tool ten years ago and have used it many times.

ddewhurst
03-22-2004, 09:30 AM
Economics question to those that have dealt with the 1st gen transmission. If a person has an extra transmission ($150) presumed good available is the economics in repairing the trans or replacing the trans ?

Question two: When the 4th (IIRC 4th & not 3rd in my case) gear synchro goes I found the synchro teeth worn ragged, the syncro cracked in two pieces (still in place) & the actual gear worn ragged.

What is the order of failure ?

The synchro wear ?

The synchro crack ?

The gear wear ?

Thanks http://Forum.ImprovedTouring.com/it/wink.gif
David

benracin
03-22-2004, 06:36 PM
Can a hacksaw cut through a socket? Pretty tough material.

And Mister Bill, when I had a stick shift to drive everyday I practiced both kinds of shifting heel toe style like a good practicing race car driver should. Have you got that heel toe stuff down yet? Otherwise I'll just pass you when you lock up the breaks letting out the clutch.

BOOYA!!!

planet6racing
03-22-2004, 07:10 PM
P-shaw! That's the beauty of front wheel drive! It's just like hitting the brakes really hard!

Actually, I've worked most of the winter on heel-toe. Problem is, it's been mostly with winter-style shoes on. I need to go practice with my driving shoes now that it is warming up...

------------------
Bill
Planet 6 Racing
bill (at) planet6racing (dot) com

benracin
03-24-2004, 10:26 AM
Any idea what size this socket is? I measure the nut as being about 1 5/8 inch across although I'm guessing it's metric.

Thanks.

ddewhurst
03-24-2004, 02:39 PM
Ben, 1mm = .03937"inch therefore 1.625 /.03937 = 41mm Remember the 1 5/8 (across flats) inch is your number.

Have Fun http://Forum.ImprovedTouring.com/it/wink.gif
David

benracin
03-24-2004, 03:24 PM
Man, I hope that's right. I'd hate to buy a socket, chop it and have it not fit. Anyone else know what size this puppy is?

ddewhurst
03-24-2004, 03:41 PM
***Man, I hope that's right.***

Thanks Ben

C. Ludwig
03-24-2004, 07:17 PM
Just use an 1 5/8". Sometimes Sears doesn't stock the big metrics so it may be easier to find and has worked just fine for me. I normally hate using english "equivalents" because of my line of work and seeing that they really aren't the same. But for anything over 1" in size the english sockets seem to work just fine.

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Chris Ludwig
08 ITS RX7 CenDiv

benracin
03-25-2004, 01:08 AM
Sorry David. I was doubting my measuring skills more than your incredible knowledge. http://Forum.ImprovedTouring.com/it/smile.gif

-- 1 hour later --

For the fun of it I tried a chisel on that nut out of pure frustration. Now I have a dented chisel. Nothing a beer won't cure!

-- 5 minutes later --

um... the beer didn't work either. I feel better though! Maybe it takes two!

http://Forum.ImprovedTouring.com/it/smile.gif

Ben.

Silkworm
04-07-2004, 02:01 PM
Those of you who have done rebuilds

What tools did you end up having to buy from Mazda, and what tools did you end up making/fabricating or simply finding something off the shelf?

PaulC

Eagle7
04-07-2004, 08:47 PM
And what is your parts list for a minimal rebuild?

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Marty Doane
ITS RX7 #13
CenDiv WMR

benracin
04-08-2004, 01:29 PM
I guess mine is just a little different since I'm taking a junk transmission and putting some of the parts into a new one. So far the tools I've bought are a drift set for hammering out those little pins, a pair of snap ring pliers and one other set of pliers that I can't remember the actual name for. They're used for taking out those washer looking rings. Those are darn handy. Also a dead blow hammer.

Tools that I need to make are that giant socket we've been talking about. I think that's it for tools!

Oh, you need a bearing puller, and a LONG one at that. I bought a normal bearing puller then got some metal stock from menards and created longer arms for the puller so now it's like 2 feet long. Works pretty crazy, but it does work.

I haven't started putting it together yet, but I know one thing that will need replacing, and that's this nut that I'm dealing with. It has a tab that gets hammered down into a slot so it doesn't spin. It's garbage once taken off.

Other than that maybe some snap rings, anything else you break in frustration, and the beer bottles that got emptied.

How's that! As far as what needs replacing in a "real" rebuild I would like to hear as well.

Ben.

bcarter
04-08-2004, 02:47 PM
I solved my tranny rebuild the easy way. I went to one of the local Mazda dealers, whose decals I run on the car, small decals, and had them rebuild it. About $800.00 CDN.

It was just easier, and I know it's right.

Probably more expensive than doing it myself, but the thought of doing the tranny is just too hellish to contemplate.

------------------
G. Brooke Carter
Wheat Buckley Racing
# 10 Challenge Car
2003 Class Champion
Calgary, Alberta
http://www.guyons.com/pictures/photos_cars/06_30_rx7_brook2_150.jpg

Silkworm
04-08-2004, 08:30 PM
I would do that except I'm already on my first rebuilt tranny, and it's dying after 2 seasons, and I've already lost one race because I couldn't get it into gear. So I want a fresh rebuild, and a spare rebuilt ready to go. I know what you mean though, I had no qualms about digging into the car, basically building the whole car myself, but when it comes to rebuilding engines or trans, I've always farmed it out.

PaulC

ITSRX7
04-08-2004, 08:39 PM
When you buy the parts, then add up the labor, we have found that the overall value of a tranny outright from Mike is a great value. $500 for a 1st gen. with no core and all his experience.

http://www.iscracing.net/clutch.htm

AB

------------------
Andy Bettencourt
06 ITS RX-7
FlatOut Motorsports
New England Region
www.flatout-motorsports.com (http://www.flatout-motorsports.com)

Silkworm
04-08-2004, 08:43 PM
Oh, the socket is 0000-09-0215

If you search their catalog, search on special tools, with no other criteria, and it's the very last tool in the list.

PaulC

Silkworm
04-08-2004, 08:51 PM
700+shipping for a 2G tranny? Is it really worth that much, in your experience?

PaulC

ITSRX7
04-08-2004, 08:58 PM
It's almost $500 in parts if you do it right - and you don't have to ship a core. The 1st gen one seems like a steal.

Order all the parts from Mazda, then buy the tools you need to actually do it with some semblance of efficiency, then tell me what you spent.

Its a value for me.

AB

------------------
Andy Bettencourt
06 ITS RX-7
FlatOut Motorsports
New England Region
www.flatout-motorsports.com (http://www.flatout-motorsports.com)

252phil
04-08-2004, 09:48 PM
Does anyone have an idea as to what shipping a tranny would cost to California? I am in the market myself and a wrecking yard wants $250.

Thanks,
Phil

C. Ludwig
04-09-2004, 12:31 AM
As long as the gears are OK you're looking at about $200 for a couple synchros (assuming that's the only problem), all the bearings and new snap rings, nuts, etc. from Mazdacomp. That is hardly ever the case.

And as for the dealers doing a rebuild, here is my story and I'll post pics tomorrow to back it up. I've torn down six non-rib transmissions. Five were from 2nd gen cars and one was from an early Ford Courier pickup. All of them exibit a very bad misalingment of the gear set. Literally half of the main transfer gear does not mesh. I noticed this on the first trans to fail on my car. I tore it down and immediately said the guy that built this was an idiot. Turns out that's the way they come from the factory. The best part is that the correct shims are not available from Mazda to correctly align the gears. The gears aren't the only problem. The two bearings that support the rear of the output shaft and the rear of the counter shaft do not sit fully in the case. One of the bearings rides nearly half way out of the case the other half way in the case. The allows the shafts to flex and aggrevate the poor alignment problem. Sending the trans to a dealer or generic rebuilder who will use the shims that are available from the factory is not the answer. Custom shims, alot of time, and an experienced Mazda rebuilder is the answer, IMO.

------------------
Chris Ludwig
08 ITS RX7 CenDiv

jrx13
04-09-2004, 03:00 AM
I think that $700 2nd gen. tranny is with the GTUs 5th gear. Probably why the price is a little higher because you have to buy the 5th gear assembly.

Silkworm
04-09-2004, 02:43 PM
ooof, well, reluctantly I'm convinced that you're right.. I'll make a final decision after I tear this tranny down and see what I really need, but you're right, if the parts cost 200, plus new gears (3-4th were grinding so I"m sure those need replacement) plus a GTUs 5th gear, and $$ for tools. Then to only to have it wear out in just over a season because of poor alignment, I'm sold.

It's only money right? <whimper>

PaulC

ddewhurst
04-09-2004, 05:29 PM
This question was asked in a past post. Anyone know the facts ? If we knew the facts maybe we could eliminate the failure.

What is the order of failure ?

The synchro wear ?

The synchro crack ?

The gear wear ?

Have Fun http://Forum.ImprovedTouring.com/it/wink.gif
David

SPiN Racing
04-21-2004, 03:46 AM
Footnote on the ISC Racing Trannies from Mike..
Have to say.. he knows his stuff. I watched him rebuild one one day while doing some work with him.. and it was really nice to see.. He prolly could have done it blindfold he knew what he was doing soo well.
Ever see a gunsmith take apart a automatic and re-assemble it? That is how he did it.. He did a excellent job... from what I could see.
I myself will be buying one from him soon as this one gets to the point I need to change it.

noresull
05-10-2004, 09:47 AM
Here's my take on Rear wheel drive, manual transmissions...

Wear generally takes place in the easier to wear parts first, like the brass syncro rings. Generally, physical gear replacement isn't neccesary due to a bad syncro unless the syncronizing teeth on that gear are worn or missing. Also, most trans', I say most becaue I haven't seen all of them, do not require shimming of bearings to allow proper bearing pre-load or gear alignment. Manual tranny's do not have hardly any shaft endplay and do not require a certain amount and gears are pretty much set where they can go on the shafts due to the position of lock rings and splines.

What I would do for a trans rebuild....
Tear it down, replace all the brass parts and bearings no matter what. Inspect each gear individually for wear and replace as neccesary taking mileage into account. If it is a racing application, I would replace gears with hardened ones only if there becomes a problem with wearing out gears pre-maturely.

Again, this is just my take, I only have 5 years experience as a Ford mechanic, and am no longer doing that, but I do feel very confident in my abilities, the only question is, do You feel confident in my abilities? http://Forum.ImprovedTouring.com/it/biggrin.gif

ddewhurst
05-10-2004, 02:10 PM
***the only question is, do You feel confident in my abilities?***

John my man, that would depend on how many tall COOL ones you had consumed. Do the two of you have THE TRANS rebuilt ?

Have Fun http://Forum.ImprovedTouring.com/it/wink.gif
David

noresull
05-13-2004, 05:12 PM
Originally posted by ddewhurst:
***the only question is, do You feel confident in my abilities?***

John my man, that would depend on how many tall COOL ones you had consumed. Do the two of you have THE TRANS rebuilt ?

Have Fun http://Forum.ImprovedTouring.com/it/wink.gif
David
Hmm Beer!!

No, the trans ain't done yet. We're prolly just gonna run the crappy one for awhile longer.

[This message has been edited by noresull (edited May 13, 2004).]

benracin
05-14-2004, 11:14 AM
Yeah, the on in the car ain't really crappy, I was just told by the dude I bought the car from that this other broken trans was better. I think it's a 12 speed from a mac truck. That's ok with the rules right? I just want to use it because I like shifting.

ddewhurst
05-14-2004, 12:46 PM
Ben & John, not trying to throw a scare at ya & not knowing what issue you guys have with the trans & depending on what the trans is doing you might not want to wait untill it craps out. As mine was on it's way south (over 2 or 3 races) the first issue was not shifting smoothly from 3rd to 4th, (the following all happened at Road America) next it'got to be a bitch to get into 4th, then at above 5,000 RPM it would kick it back out of 4th & finally it got to the point that I couldn't hold it in 4th at Road America.

Ben, did ya buy the 1 5/8 inch socket & was that the correct fit on the trans nut ?

Have Fun http://Forum.ImprovedTouring.com/it/wink.gif
David

benracin
05-18-2004, 03:15 PM
My trans used to grind going from 3rd to 4th just a little. Things may be getting a little worn in there, but I think a lot of it was due to me rushing the shift back when I didn't know the gear box well. You'll have to correct me if I'm wrong, but it seems like these transmissions like to be shifted at a slower pace. Since I started shifting a little slower, and also since I put in new trans fluid the grind has pretty much gone away. So as far as I can tell, it's still good to go. I just wanted to make this other trans work since the prev. owner told me it was "better". Plus it would be swell to have a back up.

Since I started messing with it though I've had lots of other distractions like re-doing the rear end of the cars suspension stuff. I've got a lot to do if I'm going to make the 5th. Right now I'd have to say I'm dreaming if I think I can make it, but you never know. I won't be able to afford new tires by then but that way if you beat me I have something I can blame it on. http://Forum.ImprovedTouring.com/it/smile.gif

lateapex911
05-18-2004, 08:25 PM
You know.....funny you should mention the speed of shifts and the ginding getting better...

Speed DOES make a difference.

And I know this is nuts, but I swear i have had Mazda transmisssions that were bad when I bought them seem to get better with a few months TLS (tender, loving shifting)...but how can a car heal itself???

------------------
Jake Gulick
CarriageHouse Motorsports
ITA 57 RX-7
New England Region
[email protected]

ddewhurst
05-19-2004, 08:44 AM
***I won't be able to afford new tires by then but that way if you beat me I have something I can blame it on.***

Ben, my reason for racing a Spec-7 was ECONOMICS. As the deal is converted to ITA/7 the same tires will be used. We will NOT talk about how many heat cycles are on the tires. Most people talk about heat cycles, some people talk about races & I talk about years. http://Forum.ImprovedTouring.com/it/wink.gif I got the car down to 1788 pounds but but that could be because there are pieces all over the garage floor.

***...but how can a car heal itself???***

Jake, I'm religious but I ain't touching that with a ten foot pole. http://Forum.ImprovedTouring.com/it/biggrin.gif Maybe Ben should say a few words over my car. Shucks if his words made my car faster than his I would be willing to cough up some tire money to him.

Have Fun http://Forum.ImprovedTouring.com/it/wink.gif
David

ps: I'm going to the Farm for the National this weekend & that should get the hart pumping.

DAharon
05-20-2004, 10:09 PM
Oh, the socket is 0000-09-0215
If you search their catalog, search on special tools, with no other criteria, and it's the very last tool in the list.

Whose catalog? I couldn't find that part # at Sears' website.

CaptainWho
05-20-2004, 10:51 PM
That looks like a Mazda part number.

------------------
Doug "Lefty" Franklin
NutDriver Racing (http://www.nutdriver.org)

Silkworm
05-21-2004, 07:38 PM
It's a Mazda part #.

PaulC

DAharon
05-21-2004, 09:08 PM
So where is the Mazda parts catalog available? I searched on google and looked at Mazda's website and a couple other places including Mazdacomp and Mazdatrix, but couldn't find it.

CaptainWho
05-22-2004, 12:59 AM
You can search the Mazda catalog at the Mazdaspeed web site at:

http://www.mazdamotorsports.com

You may have to be a member to order, but it looks like non-members can search the catalog. That particular socket came up as costing $80.10 a minute ago when I did a search.

------------------
Doug "Lefty" Franklin
NutDriver Racing (http://www.nutdriver.org)

Skid
05-31-2004, 01:45 PM
I have a tranny that is stuck in 4th having been run dry during a race due to a rear seal leak. Haven't opened it up but I imagine only bent splines would cause this. Is it worth a rebuild?

ddewhurst
05-31-2004, 05:26 PM
Skid, if ya take it apart please post the sitaution you find. I'm curious......

Have Fun http://Forum.ImprovedTouring.com/it/wink.gif
David

noresull
06-03-2004, 09:56 AM
Skid, I would tear it apart and find out what is binding. It could be just the Synchronizer is frozen and needs to be replaced. Or it could be a gear frozen to a bearing or the shaft. Tear it apart! http://Forum.ImprovedTouring.com/it/smile.gif