Manual Trans. shifting problems when hot.

[ssmog]

I'm having a prob. with my MX-3 GS. 5 speed, new clutch, pressure plate, throw out bearing, slave cylinder, fluid change. When the car is cold it shift perfectly fine and smooth but as it warms up and gets hot it shifts very hard, often grinding as I place it in various gears. My guess would be that the high pressure flex line between the clutch master and block is getting hot and swelling redusing the concentrated pressure required to fully force the slave out as far as it should be. I'm thinking if I replace the flex line with some nylon tubing which is capable of taking upto 1100 psi or standard flex line with a stainless braiding it should solve the problem ( I hope).
If anybody has any suggestions or comments I would greatly appreciate them..Thanks a bunch.

<small>[ June 22, 2004, 12:24 AM: Message edited by: ssmog ]</small>

[IanL]

Check the pedal adjustment first; see this post: http://www.mx-3.com/ubb/ultimatebb.php?ubb=get_topic;f=15;t=004506#000006

[hgallegos915]

Man , Im sorry to tell you but..most likely you got bad syncros. I had the EXACT same problem..of course in another car. When it was cold, it would shift fine, when warm it would grind. We took the tranny appart and walla..bad syncros. I ended up getting a junk yard tranny since that one was useless. I tried everything else before changing transmission, new slave, clutch, plate, purge lines. But yeah it was syncros.

[ssmog]

I was checking out the slave the other day, there's quite a gap between it and the pressure plate "fork" I'll call it. Can also push the slave piston in by hand with very little effort. But still that would not make a difference with shifting when hot or cold. I had a feeling it was my syncros so I just did an oil change again only added some Lucas this time. I realize it's not going to solve the problem but it may prolong a trans. R&R a little while longer 'till I have the time to locate one and change it.

[ssmog]

As it turns out it is not my syncros that are gone, the stroke on the new slave cylinder is not long enough, it's short by approx. 1/2" ao I "red/Grenned" a shim at work, fastened it between the slave and the lever controlling the release bearing and it works like a charm.

[perhapsadingo8yerbaby]

Originally posted by ssmog:
I had a feeling it was my syncros so I just did an oil change again only added some Lucas this time. I realize it's not going to solve the problem but it may prolong a trans. R&R a little while longer...

Good that a shim worked on the slave & your tranny was ok after all. Now, you probably wanna get that Lucas additive outta there or you will be replacing that tranny sooner instead of later anyway... Check out this link about additives-Lucas in particular, and be afraid... be very afraid.

http://www.bobistheoilguy.com/images/lucas/lucas.htm

[hgallegos915]

ha once..i added an additive to a gm2.5 wngine HA that thing lasted less than a week then it started smoking bluish smoke..ha so much for additives..they only make oil thicker. Im glad it was ur slave cylinder. I replaced mine on the maxima because i tought it was bad but sadly it wasnt the problem

[ssmog]

I learned the hard way never to put additives in my motor oil, I "HAD" a Mustang I that was origionally from England, quite a rare car here that's for sure........ I had added "Slick 50" to it when that **** first came out...next thing I knew I was dropping a new motor in her. I too am very glad it was just the slave cyl. What made me think of the slave is the other day I threw her in reverse then started the car, with the clutch in the car actually started backing up, kind of made me think the clutch was not fully engaging. Sure enough when I put it on the hoist I could literally move the assembly freely. Although it does piss me off it's a new cylinder there's no reason why the stroke should be 1/2" too short.....so much for genuine parts.

<small>[ July 05, 2004, 08:48 PM: Message edited by: ssmog ]</small>