zx gearbox trouble

messiah150 · Post by **messiah150** » 01 Sep 2005, 20:57

Hi there, just an update on a previous post. I've since put in all 3 new gear linkages, a new bell crank pivot bolt, new gear change lever, new thrust bearing, release fork and lever, new clutch cable, and also renewed the gearbox oil with the correct oil.
But it still crunches when changing gear, if i drive it really slow it goes in ok, but under normal driving conditions it graunches and grinds. Do you think it could be the gearbox itself thats had it? if so are all zx gearboxes the same? i have a 1.8 furio petrol.
cheers!

BrianM · Post by **BrianM** » 01 Sep 2005, 22:45

Looks like its a synchromesh problem. Had the same on a Xantia with third gear. Friend had same on a Dispatch HDI TWICE in less than 50K !

messiah150 · Post by **messiah150** » 01 Sep 2005, 23:30

is the synchromesh hard to sort out or would it be easier to do a straight gearbox swap? i've had several people say the synchro could be worn and the bloke at citroen said the same when i spoke to him earlier today. Theres several citroens at my local scrappy, just need to find which boxes are compatible.
cheers!!

howiedean · Post by **howiedean** » 02 Sep 2005, 01:24

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by messiah150</i>

is the synchromesh hard to sort out or would it be easier to do a straight gearbox swap? i've had several people say the synchro could be worn and the bloke at citroen said the same when i spoke to him earlier today. Theres several citroens at my local scrappy, just need to find which boxes are compatible.
cheers!!
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
The gearbox will probably be the same be3 design as used in most of the citroen/peugeot range however different ratios are used for different applications. I have been told that the gearboxes for td's are the same, you might find that all the petrols are the same as well.
Regards

sooty · Post by **sooty** » 02 Sep 2005, 01:34

I might be wrong, but I don't think the petrol gearboxes would be strong enough to cope with the torque's of the diesel n/a or td.
But as your's is a petrol it won't matter, except that the ratios of a diesel Gbox may not suit due the low revving of a diesel.
Best pop into Halfords and have a sneak in the petrol and diesel manuals and compare the ratios.

Post by **Peter.N.** » 02 Sep 2005, 04:22

They usually have sellophane wrapped round them (the manuals not the gearboxes) I missed the original string, but I suppose the clutch not disengaging has been mentioned? It unusual for all the synchros to go at the same time.

messiah150 · Post by **messiah150** » 02 Sep 2005, 04:45

I've already got myself a manual so i'll check it out later. I was thinking the same thing about the different ratios. Our local scrap yard has a volcane diesel, so i'll check to see if its worth getting this one
cheers

jeremy · Post by **jeremy** » 02 Sep 2005, 11:59

Diesel engines rev to a max of 4500, you petrol goes considerably faster. Make sure you get the correct box as for example BX TD, 26 MPH per 1000 rpm in 5th, BX 16 valve 20 - so put the TD box in a 16 valve and you will do 180MPH - get the idea. (or 16 valve in TD and max speed is 86)
I know you've probably checked but does the clutch free well away from the floor? These gearboxes always seem to 'snick' slightly when engaging gear and I would not describe the change as being anyway near as good as others were achieving an the 1960's but having said that the boxes seem strong.
Some people have good experience of additives in these boxes - Slick or something may be worth trying - much cheaper han another box.
Jeremy

uhn113x · Post by **uhn113x** » 02 Sep 2005, 13:20

On my ZX TD at least, the gearing is much higher than on a petrol model.
Additives are OK for reducing noise, but usually make the synchromesh worse by lessening friction.
Have you tried double-declutching? Easier than changing the gearbox!
Pre 1935 cars nearly everyone had to!
We'll assume the clutch is not dragging - does it crunch in reverse when stationary? If it does, it is the clutch, not the gearbox.

messiah150 · Post by **messiah150** » 03 Sep 2005, 00:05

its definately not the clutch, everything was fine until the release lever on the clutch snapped due to being badly rusted and corroded. since putting in a new thrust bearing and lever and release fork its started playing up. Theres no slip on the clutch whatsoever and if i were to "dump it" the wheels spin. Gonna try adjusting the clutch later on today or tomorrow and see if that makes any difference.
I just cant fathom it out, seems like this cars got a mind of its own sometimes.

sooty · Post by **sooty** » 03 Sep 2005, 00:28

If this has only happened since you've repaired the release lever, then its suspect that the clutch mechanism maybe at fault. If you select reverse gear at any time hot or cold, does it engage cleanly or crunch the gears. If its cleanly then you should be OK, but if crunches then there maybe a fault somewhere. My clutch takes up drive towards the top end of its travel.

messiah150 · Post by **messiah150** » 03 Sep 2005, 22:04

sometimes it crunches sometimes it doesnt, whether its hot or cold doesnt really affect it. shifting down is the biggest problem, as it crunches and grinds quite hard, going up the gears isnt too bad as long as you take it real slow

sooty · Post by **sooty** » 03 Sep 2005, 23:45

In that case, from what you say. I think the syncros are worn as mine tends to do that if I change down at too high revs, 4th to 3rd or 5th to 3rd at 60/70mph, it don't crunch as bad as yours, you just can feel it as it engages, but otherwise at sensible driving its ok.
So it looks like a replacement box for the easiest.
good luck

fastandfurryous · Post by **fastandfurryous** » 04 Sep 2005, 14:42

From the sound of this, I recon it's a clutch not fully releasing, especially as you say it's only happened since the clutch mechanism was worked on, and it's come on suddenly. Synchro's wear very slowly, and gradually get worse and worse.
I've had BE type gearboxes with well over 300k miles on before, and the synchro's were all still good. I would try adjusting the clutch a little to ensure that the bite is in the middle of the pedal travel.
If it's an auto-adjuster cable, maybe the adjuster has worn, and it's now not giving enough travel at the gearbox end? I've seen these before not work properly, and give all manner of problems. Best bet is to ditch the (rather rubbish) auto adjuster and fit a standard cable. much more reliable, and you can adjust it to suit your own preferences.

messiah150 · Post by **messiah150** » 07 Sep 2005, 20:51

mines just a standard clutch cable anyway i think so i'll see what happens when i adjust it later. fingers crossed its gonna work!!!