gearbox change help.. Please!!
 

hey guys,

not an owner but a mechanic for an owner.. done a gearbox change on a 96 WRX turbo 4x4..

got everything back together and ok, although now the car wont select any gears, the clutch cylinder piston pushes the bearing fork about 10-15mm which doesn't seem like enough to release the clutch..

when trying to engage a gear it's as if the bearing has packed up. when the box was off the bearing had an excessive amount of movement on the pressure plate, not sure if this is normal.. and i couldn't get it to release from the clutch.. so when putting it back in i left the bearing in the pressure plate and cunningly managed to get the fork to lock on with the bearing..

does anyone have any ideas of what could be wrong, or if the bearing is just dead?? First time working on a scooby so not to sure..

any help would be of benefit.. if anyone's feeling generous to offer tech advice - 07890048855 - Aaron.

can you select any gears when the engine is off?

yes can select gears with the engine off.. so suggests that the linkage is ok.. also the clutch pedal when pressed just stays on the floor and comes up really slowly about half way and doesn't feel like it's doing anything.. so i'm guessing there's air in the slave cylinder?? but still no idea why it isn't selecting gears.. any ideas?

yeah deffo clutch problem, no cutting the drive from the engine, release bearing or slave cylinder.

has the fork sliped from behind the thrust bearing ( as you prob know its a "pull" type clutch on the classic scooby and the fork sits into a holder, sometimes when fitting with all the moving about this fork slips off you should be able to slip it back on if you can get a tourch light into the hole and then locate it,
hope this is all it is and is an easy fix :thumb:

no the fork doesn't look as if it slipped off the bearing as when i pull on the fork it seems like its all in the right place..

could the problem be air in the slave cylinder?? As i said there is only around 10mm travel in the fork which to me is no where near enough..

Sounds to me as either the bearing has gone or the fork hasn't actually located itself properly on the bearing. As you said push you do know its a pull type clutch meaning if you pull the fork towards you and your standing at the front of the car you will struggle to move it. If the fork is flapping around then bearing to pressure plate is your issue.

There should be no reason for air to enter the slave as you haven't touched it. But if you want to bleed the slave make sure you unbolt the 2 bolts and turn it upside down to bleed as you cannot bleed it correctly in the mounted position.

Oh and the reason you couldn't get the bearing off the pressure plate was because theres a locking ring around the bearing which locks the mating surface of the bearing into the pressure plate. The retaining ring is on the inside of the pressure plate and until this is not removed the two are not seperable.

If your still stuck i don't mind calling you to help.

yeh i kno its a pull type clutch sorry.. the fork seems in place, even took out the shaft that goes through the fork to check. seemed fine when i pulled so don't think that's the problem. the fork isn't flapping around. the slave cylinder had a leak on the rubber so replaced that which would allow air to enter but wouldn't of thought enough to stop the clutch working.

the reason i say air in the cylinder is because the pedal stays on the floor and needs to be pulled up every time. the car will engage gear when off but when running it wont go into gear, it just starts catchin each gear and tries to pull away without the clutch.

ah i see, didn't know that. i would of been better off taking the pressure plate off then and putting the bearing on the fork for assembly so culd of been sure.

turn the slave upside down so the nipple is facing up so air rises to the top or so that its facing the back of the block?

Extract from SccobyMods>>

http://www.scoobymods.com/forums/ble...85.html?t=3685

Remove the rubber cover off of the bleeder fitting. Have a helper press the clutch pedal all the way to the floor and hold it there put one end of some clear tubing on the bleeder and the other end in the catch tank.

Crack open the bleeder (make sure the helper keeps their foot to the floor) Watch the end of the slave cylinder move in (you'll see it move at the end of the thing the bleeder is in) once it's stopped close the bleeder

Now comes the part that is different than bleeding the brakes. Have your helper take their foot off of the clutch, get out of the car move the seat back grab the clutch pedal and pull it back to its normal resting position (it will be stuck to the floor) Now watch while the pin in the slave that moved in moves back out. It may take a few seconds. When this happens fluid from the reservoir will get lower, be sure while you are doing this the reservoir never runs dry!

Repeat the procedure till you see clean fluid coming out. Three or four times should do it. Fill the reservoir to the MAX line before you put the lid back on.

The part that had me confused about the procedure was having to hold the pedal back out till the spring in the slave sucked fluid in.

GoodLuck

Yes turn the slave upside down it's always helped when i have bleed mine. So nipples facing upwards and yes so air rises to the top and is forced out with the hydraulic.

It could even be a knackered slave.