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View Full Version : HELP..... Tranny Woes!!


DareBee
08-19-2003, 11:26 AM
I am hoping someone can shed some light on my Tranny situation in my 2nd gen RX7.
My manual trans is currently making a ticking noise. I use the analogy of it sounds like the baseball card taped to the front forks of your bicycle with the card running on the spokes (come on we've all done it).
I had better start the story at the beginning.
A couple of months ago I was running my usual autocross series (This is about all the car (90 RX7 N/A) is used for). When I had a horrible 2 - 1 downshift; It just crunched in real nasty. That is when this tranny (A rebuilt 86 model) started to make the "card in the spokes" noise.
I figured I bent something a bit but wasnt going to quit.
2 runs later on one of my massive launches (about 7000 out of the hole with 15 feet of wheel spin to keep from bogging) just starting to hook up real nice and the tranny GRENADED!
Toss a grenade under your car and see how it feels!

I have now rebuilt my original tranny (new bearings, synchros, shift forks). Did Imention I am very fussy and I also have a lot of industrial mechanic experience (in my defense).
It has worked great! I put on about 80miles around the country side and then to my closest event. I was staging and noticed a very faint ticking from below and went out on my first run and immediatly upon starting the ticking got extremely loud.
EXACTLY LIKE LAST TIME (FOR F*$% SAKES)
I didnt race any more but I did drive the car home 60miles without incident.

Let me try to explain the ticking better
When the clutch is engaged and the tranny in neutral all i hear is the usual gear whine (at any RPM or duration).
When I speed up or slow down (reverse included) the ticking changes frequency relatively.
In first gear the ticking is very loud.
In the other gears it is very faint. I cant usually hear it over my very loud exhaust untill I am decellerating.
Again I will say that the ticking doest not exist when in nuetral bu tranny rotating.
The noise is also very distinctly coming from in front of me (sitting in seat).
Fresh rebuild and I didnt even crash the gears (yet). Does anybody have any idea what may be wrong.
I know I have to take it apart.

Very, very, very frusterated!

Thanks.


__________________
Cheers!
Derek

MiG-29 Foxbat
08-19-2003, 07:26 PM
Derek, did you call Dave at Mazdee's yet? I can call him for you to see if he has a tranny lying around...or I can forward your message to him.

Is yours a ribbed case one or not? I might be willing to pick it up and bring it to the next event and we could install it between rounds:o

DareBee
08-20-2003, 07:25 AM
Any chance you would be willing to let me know who you are Mig?
So far my quickest time for dropping the tranny is 2.5hours then there is reinstall yet!
Also after $800 this rebuild my family will not allow another $400 for a tranny (from A-Spec). I was hoping to split this unit and repair/rectify the problem.
Having an idea what may be the problem will possibly save me days or the alternative of taking the split tranny to Dave (at least a 140K drive for me)

MiG-29 Foxbat
08-20-2003, 08:54 AM
Well, I was trying to remain cloaked, much like a Romulan Warbird, but I test drove your car on Sunday.

I suggest you call Dave then, he'll tell you straight up what's wrong. He's not that far from me if you want me to ferry the repaired one back to you.

My brother's-in-law uncle also has worked on tonnes of RX-7's, he's a mechanic, so he could give a second opinion.

Cheers!
08-20-2003, 02:33 PM
Derek,
Posted your question at nopistons.com

http://www.nopistons.com/forums/index.php?showtopic=24541&st=0&

see the thread.

DareBee
08-20-2003, 06:38 PM
Hey thanks Cheers!

I also have it posted team FC3S forum.

Cheers!
08-20-2003, 06:53 PM
The nopistons.com forum has the most knowledgable people out of rx7club.com, teamfc3s.org. Two highly regarded engine builders, and many ex mazda mechanics visit it frequently.

DareBee
08-20-2003, 06:55 PM
I have joined and posted between these last 2 here

Cheers!
08-21-2003, 03:25 PM
check your PM.

btw did you check the diff/drive shaft

MiG-29 Foxbat
08-21-2003, 05:39 PM
Derek, I found that in neutral, with the clutch pedal released, the noise and vibration would appear when the engine was revved.

It was OK when the clutch was in.

This rules out the diff and driveshaft. I think it might be a bad bearing on the input shaft.

DareBee
09-03-2003, 08:43 AM
I have gritted my teeth and slapped in an unproven used tranny.
Seems to work well.
First test will be Saturday (6).
I figure I will see most of you there.
The diagnosis on the Tac Tac noise just got real easy as there was a piece of gear tooth on the oil plug. I will assume from first but only time will tell.

Thanks

Cheers!
09-03-2003, 10:02 AM
woah... good thing that gear tooth didn't make its way into another gear. Else it would have been bye bye tranny again