Gearbox about to die?!?!

[AJ]

i don't need any \"practice\" double clutching mick, been doing it for years..........

[Mick93]

My advice was offered to the author not you AJ. If it is so useless why do you bother? Because cars have had syncromesh gearboxes for at least 25 years I don't know why you even learnt unless your a truck driver????? You were the one claiming how useless it was so why do you do it????

[JBT]

This should be good

[Sheck]

How about addressing the original topic of discussion here?

Hows that gearbox goin mate?!!!!
Checked the oil or anything?

Dave

[Craig]

How about addressing the original topic of discussion here?

I was thinking the same thing!

Change the oil to a Castrol 75/90 Synthetic, and whilst your at it replace the selector bush (white bit of plastic on the bottom of your gearstick) and replace the 2 rubber boots as well as chances are they'll be perished.

After step 8 you'll see the selector bush http://www.miata.net/garage/shiftboot.html

Craig

[JBT]

I'd be starting with the clutch hydraulics as the most likely cause.

[Mick93]

You guys are right. The problem sounds like syncro rings and in our car probably not worth replacing due to cost you can pick up a good second hand gearbox probably more cost affective. Theres one in the for sales it might be go.

[JBT]

Still think it's hydraulics.

[Mick93]

Dose it crunch in every gear. The test for a clutch not engaging propley is would be to try changing through the gearbox at low revs this is so your not changing gear when the gearbox is in sync. The reason it is intermitted is that sometimes you will change gear your timing will be spot on it which case there would be no crunch. Is your gear shift slow to engage?

[AJ]

My advice was offered to the author not you AJ. If it is so useless why do you bother? Because cars have had syncromesh gearboxes for at least 25 years I don't know why you even learnt unless your a truck driver????? You were the one claiming how useless it was so why do you do it????

gee, where to start???


i love the way ppl ASSUME they know everything about someone, when really they know phk all

do i double clutch a modern car that only gets road use????.....well, the answer to that is no, there is no point, which i believe was my original advice to the author mick, & you're absolutely correct, it is about 25 years since a car came out without synchromesh on low gear.

& yes i AM a truck driver/owner, in fact, so was my father & he started teaching me to drive crashboxes when i was about 12, not a skill i need with the truck i drive today, mainly because most every modern truck has a synchromesh gearbox, where the manufacturers advise quite strongly NOT to double declutch as you will cause UNDUE WEAR & TEAR on sensitive clutch components.


i was claiming it was useless yes, because i happen to know what i'm talking about, unlike others who flap their gums no matter what they do or don't know.


IMHO it is the clutch hydraulics, simply because synchro rings will outlive even the roughest drivers this day & age.

[JBT]

The test for a clutch not engaging propley is would be to try changing through the gearbox at low revs this is so your not changing gear when the gearbox is in sync.

Whaaaaaat The problem is dis-engagement.....or lack of. The test is to check for leaks at the slave and master cylinders first, then check free play etc. and see how much travel you're getting at the clutch release lever.

The reason it is intermitted is that sometimes you will change gear your timing will be spot on it which case there would be no crunch.

It is only happening on downshifts according to the first post and this is fairly typical symptoms of incomplete clutch disengagement caused by stuffed hydraulics. Half the time you don't even need the clutch on an upshift so any declutch action will do the job then.

I doubt that it's synchros or gearset problems unless the transmission has been absolutely hammered by a gorilla with no mechanical empathy.

[Mick93]

Sometime you can't see a leek in a slave cylinder (and your right it is dis engagement sorry misslexia). Syncro rings can be abbused in all manner of ways flat shifting will trash rings quiker than you think. I don't think it worth going with your pissing comp (that you started) AJ as I have only ever used crash race boxes and no truck ones. I mearly pointed if this was a skill he (not you) wanted to attain (he may want to do trackdays) that if done correctly won't damage his car he would more likely trash his clutch slipping it off the start.I thought as a truck driver you would know that the reason they don't want you to double de-clutch anymore is that they are making truck gearboxes lighter but the torque a truck engine makes is better than ever and they don't want to stress the clutch. This is not as big an issue in a 4 cylinder 90hp car. You might not see the point but your obviously a truck driver and not a car driver. Just let the wind blow through your hair on your sunday drives.

[AJ]

beg your pardon mick, but i do believe you fired the first shot in the little war of words & just for the record i am both....a car driver & truck driver.........i reckon i was up to my elbows in engine parts & tracking, hill climbing etc while you were still a stain in your old mans undies.

[JBT]

I mearly pointed if this was a skill he (not you) wanted to attain (he may want to do trackdays)....

Not required for track days with a synchromesh gearbox. One declutch with heel/toe techniquewill do the job.

[Mick93]

Deez this skill you will read heaps on and trust me you can go to different performance driving schools and each one is different, infact most gearboxes are different. But getting back to your gearbox check you clutch as that will be the easiest thing to check then if it is your gearbox you might have to bite the bullet and fix it. Don't listen to people who want to PooPoo on you wanting to learn new skills better, to screw up a $400 gearbox learning to do something that to try on something expensive. The real advantage of an MX5 is that you can learn things inexspensively. I figgured out who AJ is everybody it must be Allan Jones (former F1 Champ) I was there in the pits the day he told Mark Skaife he was nothing too. Its easy to poor crap on people like Deez for trying too improve his skills or me. You just live in your glory days being a back marker in a EH Holden. If this made you feal like a big man without popping a little blue pill good luck to you (see put you down without mentioning you dad or your mum!!!)