Tailsaft/gearbox Issue? R32 With A 25 Box

[sean133]

So I just finished putting a rb25 gearbox in my r32

Got the custom tailshaft to suite

But basically, I can put the car into all gears, while the car is on, and my revs don't change, it doesn't stall, it doesn't move at all. But I need to use the clutch to put it into gear

It moves ever so slightly then just nothing

My mate said my tail shaft is too short, but it splines onto the gearbox which I can easily tell, and I ran the car on jack stands with no tailshaft in, and the spline on the back of the gearbox spins

Does any one have any ideas

[89CAL]

Have to use the clutch to put it in gear, thats not unusual?

cant you put the back of the car on standsso the wheels are in the air and then (carefully) put it in gear and have a look. Obviously if the tailshaft doesnt spin at all then it isn't engaging the shaft out of the gearbox. If you want to confirm this, you could use some spacers and longer bolts on the diff flange for the tailshaft so that the front will go further in the gearbox. Again be careful doing this, while on stands, and be gentle putting it into gear.

It's just something to check it, dont go driving around like that because its not good at all

[sean133]

I wrote that out just for reference sake, in case someone asked can I slide it into gear while running without using the clutch

[sean133]

And yeah haha I actually wrote in my first post I did that,

Thinking it may now be the slave cylinder, the pin is seized and isn't fully de compressing, leaving the thrust bearing pushing on the clutch still when the clutch pedal is disengaged

Being like that the clutch slips, so it grabs slightly but very weakly, which is my problem

[sean133]

So basically tailshaft spins but very weakly, not enough to move the car

So it's clearly a clutch engagement issue I would say

Isn't a diff issue as there's no noises and the wheels spin fine

[89CAL]

If its a 25 box and the slave is stuffed, it means you wont get as much clutch disengagement rather then engagement. So you should have the opposite problem, hard to get into gears, but has full clutch contact when the clutch pedal is released. To confirm this you could just remove the slave and leave it hang. Then start the car in first with the wheels in the air and they should spin happily. Otherwise if its an issue with how much clutch slip it has (more then normal) then you could try the same thing but then try and start the car in first with it on the ground. make sure you have plenty of room obviously, because if it does start and the clutch is engaged it will move forward until you hit the brakes or turn it off.

what was the condition of the clutch that went in it? Was the gearbox known to be working before it went in the car? From memory the output shaft will spin a little bit with the car in neutral with no load on it

The clutch might have an issue

[sean133]

Clutch was good I've been driving with it for a year

Box came out a car I wrecked

If the slave pin isn't releasing all the way then it'll give me the issue what I'm having

That's a good idea about taking the slave of and driving it in first (or reverse for me as its in the shed..)

[sean133]

100% not a clutch issue (as in pressure plate clutch plate flywheel etc)

Definitely not a diff issue

One thing I noticed, when my rb20 was out, I could attach the box then the slave after,

With the rb25 gearbox on, I can't attach the slave cylinder after as its too stiff, which makes me believe it hasn't retracted all the way

So I believe th slave is stuffed

If that makes sense

[sean133]

But I lik your suggestions and help, it all makes it easier for me to figure it out!

[sean133]

Also box and slave have been sitting doing nothing for about 2 years, could be a contributing factor to a seized slave

[89CAL]

Yeah might have a siezed or damaged slave. I got mine honed and re-sealed from a brake shop for $50. Looked and felt like a brand new one. They can re-sleeve it if the bore is to wrecked. Give that a go, sounds like it needs a rebuild anyway

[sean133]

Cheers for your help man I appreciate it

Took the slave out and wheels spun in gear as they should, fiddled with the slave and got it to retract properly and threw it back in, and car drove right for a minute before the slave got stuck again

Ordering a new slave today

May aswell just get a new one I suppose

[sean133]

$50 ain't badly priced either

[89CAL]

I couldnt' source one locally and after having my car off the road for 3 months, and not wanting to wait over the weekend for parts, I thought it was better to just get it re-kitted. Only took them about an hour as well.

[sean133]

yeah not bad

nissan want around 180 brand new oem

got a mate hooking me up with a brand new oem one for 75 through sprints so cheering

comes in tomorrow