Trans input shaft seal leaking

[Dirty Fingernails]

Hi all. My first post here. I am the proud owner of a '90 Festiva with 310,000 miles, original engine, second transmission. Although it's not my main ride any more, I still like to try and keep it going. It's been an amazingly reliable car. I'm a pretty good shadetree/home mechanic, and have rebuilt three or four car engines in my time, and a manual transmission.

I've now discovered the input shaft seal on my 5 speed manual tranny leaking and causing the clutch to slip. I have new clutch parts, flywheel, and rear main engine seal ready to install, but didn't realize it was the tranny leaking until I got it all apart. Other than the leak, it's working fine, no noise, input shaft not wobbly, etc., and I really don't want to overhaul it right now.

Looking at the trans, it doesn't appear that the seal is replaceable from the outside, or is it? I only have the Haynes book, which doesn't cover transmission dismantling. I just want to know how much is involved in replacing the seal. My guess would be that you can unbolt the bell housing section and lift it straight up and off, and then get to the seal. But, I don't want any nasty surprises like parts falling out, etc. that I'm not ready for.

Anyone out there able to help or point me in the right direction? Thanks so much.

[Damkid]

I'm not too sure if the seal can be replaced without dismantling the case (someone will chime in that knows for sure) but if you add your location to your profile there may be a member near by thats willing to help you out

[Dirty Fingernails]

Thanks! Just updated my profile.

[jglutz]

Welcome to the sight.

310K....any major work to the engine?

MTX input seal is changed from the inside of the housing...the tranny must be dismantled. The MTX is not that bad of a job if you have the time and space.

[Dirty Fingernails]

No, the engine is amazing. Only externals have ever been messed with - alternator, water pump as maintenance every 120k, timing belt every 60k, dist. cap & rotor & plugs & wires as needed. I did change the valve cover gasket once when it started leaking. I'm the second owner, so I'm sure of its history. Bought it from my buddy when it had only 104K miles, he bought it new. Religious oil and filter changes every 3K, no exceptions. Even now, only minor, quick smoke on startup, and that's it.

Can the tranny just be opened up, seal replaced, and then bolted back together, or is there more to it? If there is, I'll just go ahead and get a factory manual.

[SIBladerunner]

I thought the trans had parts that had to be pressed apart in order to get to that seal?

[ejp2fast]

for the money, you're best bet is to put another 5 speed tranny in there... that'd be my advice.. you aren't leaking fluid are you?

[roycehof]

To replace that seal you will need to split the case. Best to get the manual on it because there are detent balls and springs as well and roller ball switches which need to be removed first. If you work carefully you may not need to do anymore than to pull the input shaft and replace the seal, however to remove the inout shaft you will also need to drift out the roll pins for the selector forks. Pretty tricky stuff if you never worked on tranny before. Again I strongly suggest getting the maual for the transmission. I think Mazda calls these type of transmissions "M5". The parts (including a complete rebuild kit)were still available at Auto Zone (at least they were 2 years ago).
Good Luck!

[Dirty Fingernails]

Thanks. That's exactly the info I was looking for. I have done a manual trans before, just not the Festiva. With that other unit, an AH Sprite, it was the same way - shift rod detent balls having to be removed first, and without the manual you would be pretty much screwed .

[ejp2fast]

good luck! glad you found your answer.

[Dirty Fingernails]

Success!

Just a little follow up. Got the factory manual, and the disassembly instructions and pictures are great. I don't know if I'd recommend it to someone who hasn't been into a transmission before, but really the only part that might be majorly confusing for a first timer is the bit about the interlock pins between the shift rails. I tore it down this evening and got the new seal put in the case, and will re-assemble Friday night.

Maybe I'll take a picture and upload to show the carnage on my dining room table. Yes, my wife was mortified, but it's been cold here lately, and I took great precautions not to damage the table .

[Dirty Fingernails]

Pics

Here are a couple:

[Dirty Fingernails]

More

And a couple more:

[ejp2fast]

carnage on my dining room table. Yes, my wife was mortified, but it's been cold here lately, and I took great precautions not to damage the table .

Sweet!! Transmission on the dining room table!!!! your wife is much more forgiving than mine... there is ABSOLUETLY NO WAY that'd fly at our house.. .. i haven't tore into a transmission yet... thanks for the pics!

[88FestivaLX]

I've noticed that my 5 speed is leaking. Not bad, I can just see drips on the bottom of the case....I'll bet mine is that stupid internal seal, ha