1jz/r154 clutch problem

[japlish]

hey all,

i recently bought a mx83 that's had a jzx90 ijzgte and r154 installed in it. it runs a npc clutch kit with brand new clutch master and slave units.

the problem: when engine is running and the box in neutral you cant select ANY gear even when the clutch pedal is fully depressed, if you turn the engine off, put it in say 1st and start the car with the clutch pedal depressed it'll start moving straight away but thats all you can do.

i took the stop out of the clutch pedal and re-adjusted the clutch master rod to suit too.
i even had a mechanic friend help me bleed it so its done correctly as far as i know??
we even put a longer rod in the clutch slave to see if that worked, nada.

any idea's??
p.s. the car was never driven before putting the new clutch setup in.

[allencr]

start the car with the clutch pedal depressed it'll start moving

Doesn't it disengage & slip a bit?
Bad clutch or fork.

[JP]

clutch plate installed with the outside-face against the flywheel bolts? You only need about 10mm of fork movement at the slave end of the fork for it to disengage. The last jzx90 I did had 14mm of travel at the slave with the clutch pedal fully depressed.

Clutch plate is fairly easy to check, just unbolt the slave, remove the fork and unbolt the pressure plate bolts through the inspection holes. Then you should be able to slide the pressure plate far enough back to see uf the plates in wrong.

[lexsmaz]

Does the pedal feel good, as in no slop at the top of the travel ?

When you bolted up the pressure plate how much crush did there seem to be as you were doing up the bolts, basically what i'm trying to say is that what i do is push the pressure plate on to the assembled flywheel & clutch plate firmly by hand & say just give the bolts a turn or two & then look at how much distance there is from the flywheel mounting surface to the opposing pressure plate surface if there is more than around a 5 mm gap that you have to close up you will most likely find the clutch will drag or not disengage, as the pressure plate assembly cannot physically move the pressure plate clamping ring that much distance to disengage it from the clutch plate once its all bolted down ..

So if the pedal feels good i would suspect you have too much crush happening ( wrong clutch plate etc ) or as JP said you might have the clutch plate in back to front & its hitting on the flywheel bolts ...

[PeteH]

Hi,

It is highly likely that the clutch pedal bracket hasn't been modified properly and you aren't getting full stroke at the master cylinder.

takai discovered, and posted, how much extra work is required to get an A70 clutch to work properly - http://www.toymods.net/forums/showthread.php?t=39733

When I did mine, MX83 + 1J + R154, I used the 2nd hand clutch that came with the gearbox. This worked great until I installed a new clutch which needed more throw to fully release the clutch.......I ended up in the same boat as you.......car off all gears, car on no gears and a clutch that wouldn't fully disengage.... To gain the extra throw, read: the correct full travel, I had to remove the clutch bracket and space it out from the firewall.......oh and also lengthen the maso rod and redo the third location tab for the bracket.

Btw increasing the length of the rod in the slave does not gain you any extra travel, you have just moved the position of the slave pistion in the bore...........the master is still pushing the same amount of fluid....

Cheers,

Pete

[Dropbear]

hey,
1st of all i suggest you check the slave cylinder pushrod travel with full pedal depression, 10-15mm or so should be sufficient. If there isn't this could indicate a number of things.

- The master cyl pushrod is't adjusted correctly
- There isn't enough master cyl pushrod travel.
- The master and slave cyls aren't matched ie slave daimeter too large/ master cyl too small etc.
- There is still have air in the system.
- The flex hose is shagged and expanding.

If there is sufficient slave cyl travel it would most likely indicate a problem with the fork or clutch assembly it's self, as suggested above friction plate may be fitted backwards and hitting on flywheel bolts.

I've seen fork pivot points worn/stretched to a point that they no longer have enough leverage to operate the clutch.

Incorrectly machined flywheel not allowing the pressure plate to move enough to release.

Faulty pressure plate or something jammed in between pressure plate and friction plate.

Hope this helps

cheers

Tim

[japlish]

hmm, well i got too talk to npc clutch who made the clutch and apparently if the throwout bearing carrier setup...thing is installed incorrectly(which is possible) it can cause this problem?

i checked the travel on the slave cylinder and it would move around 10mm even more actually.

and there's no way the bore size in the master is incorrect as 99% of toyota's have the same master cyl bore size.

i didnt install the clutch so it may be possible that the plate is in backwards or that carrier was installed wrong.

and its not a ma70 clutch pedal/bracket, i think its a jzx90 version? (i have a genuine jzx81 setup in my other car and it doesn't look like that either)

i'm pulling it apart as we speak.....i'll check your idea JP

[japlish]

well i just checked and the clutch disc isn't in backwards so scratch that.

[Dropbear]

oh i just thought of something else to check, i'm not sure what setup you have but if it's a bearing make sure the spigot bearing isn't seized or bush isn't damaged/too small preventing the input shaft from spinning freely

[japlish]

na its not that as i can spin the clutch disc by hand when its on the input shaft

[Dropbear]

hmm may have out wires crossed there by spigot bearing I mean the one highlighted in the following pic, if it's seized the input shaft will be "fixed" to the flywheel.

[japlish]

na i understood what you were saying but that would mean the input shaft still wouldn't turn, and it does

[japlish]

well i got it all back together yesterday after getting both the gearbox and clutch back from the shop (nothing was wrong with either of them!!)

i also put my GENUINE gx81 clutch pedal setup with master cylinder in and its STILL NOT WORKING

[allencr]

clutch back from the shop (nothing was wrong

Tough to check a clutch if you aren't a manufacturer or re-builder, were they? If they don't have the equipment, it is pretty much a 'put it on the floor & use your heel on it while scratching your ass' kind of test. Hope they didn't also charge to 'check' the trans.

The clutch won't disengage if the fork flexes & hasn't pushed it far enough, the disk is extremely bent, the disk is way too thick, the pressure plate isn't adjusted right or is broken.
Good luck.

[allencr]

na i understood what you were saying but that would mean the input shaft still wouldn't turn, and it does

I understand that the transmission must be mounted, minus the PressurePlate & disk, to see if the input shaft would turn, but I'd just stick my finger in there to feel the bearings inner race movement.