need help: gearbox/clutch problems

[disturbed1]

havent had much luck asking on other forums so will copy and post details here.

bit of an introduction - i bought IJ tremec box/conversion for my 7m and have had some issues with crunching syncros. the following post is how ive tried to overcome it.

sorry for the long read.



i recently put my car back together after getting some1 else to rebuild the box due to crunching 3rd gear issuse... i replaced the whole 3rd gear and had all the syncro mating surfaces shot blasted with 120 grit garnet to remove any glazing, so they brass syncros were grippy as fuck and locked up easy as... also took the chance to upgrade from a 10 spline ford to a 26 splin input shaft. now the gearbox was assembled and now ive got the whole car bolted together i have encounted a major problem..........

while the gearbox was being rebuilt, i also had the clutch looked at and was shown signs of wear... the clutch is a osgiken twin plate)

we had to machine 1.5mm off the flywheel cage to preload the pressure plate properly so the fingers went flat when bolted up. other then that no other changed besides resplining the clutch plates to 26 spline since i upgraded my input shaft on the box at the same time it got rebuilt

so what problems am i having

with the car jacked up on axlestand, i start the car = all sweet.
press the clutch in and the clutch rattles like a typical twin plate = nothign unusual, feels nice and normal
now slowly try select a gear by slowly and softly moving stick into a gear and allthough it will not go into gear - even with considerable force, the rear wheels start driving

if i turn car off and try put into gear - it is also near on impossible, even if u try force it.
however if u rock car back and forth, they will go into gear easy as (if u rock car back, slips into gear - let it rock forward back where it was and u cant take it back out)

if u put the car into gear with motor off and start the car - the car is truying to drive itself nstantly while cranking. if the car is runnign in gear on axle stands and u press the clutch in - the wheels wont stop spinning and its impossible to stop them by spinning (even with handbrake it just stalls motor..

now i know its runnign a sintered bronze spigot bearing which was a tight fit, slipped onto input shaft easy enough, but was failry sticky to spin. the gearbox and all slipped on easy enough when assembling, but i know this wont be helping matters at all.

so basically not sure what could be the problem

either 2 grippy syncro surfaces
input shgaft been preloaded to much
spigot bearing to tight
clutch not releasing (havent touched the slave/master setup at all)

anyone else had similar situation??

i know i had problems with syncros coming loose in a r154 jamming the input and output shaft but this made the wheels want to drive even when in neutral. so dont think its the same as what im sufferign now.

 

[disturbed1]

took the motor and box out yesterday.

pulled the gearbox off and the clutch off and didnt notice anything strange

went to take the spigot bearing out and it basically fell out, pulled it out with finger with ease so the tight fit on the input shaft must have become an interference fit by time the spigot was hammered into the crank and the spigot has been wizzign around in the crank and worn it down considerable. so i guess that was the high pitch squeel i was experienceing

anyway. made up another 1

smached it in crank, double checked the ID and it was spot on

put the clucth and bellhousing and fork etc all on minus the gearbox. sat it in thew engine bay - hooked up the slave and made sure the clutch plates were releasign fine, which they appeared to be. could stick my fingers up through the relese bearign and wobble both plates up and down freely.

so pulled the motor back out, bolted the gearbox on good and proper then while sitting on a hoist/tire out of the engine bay, while the gearbox was in gear, i stuck a metal pole on the clutch fork and yanked it back (effectively pressign the clutch and disengaging it) while dad spun the crank over, yet the output shaft on the box still spun with the engine. with the yoke in - no matter how hard i tried to restrain it i couldnt.

im thinking this isnt normal so holdign back from putting the motor in yet again

anyone got any new thoughs?

 

[jdub]

And this has to do with 7M-GTE tech in what way?

Thread moved...please pay attention where you post.

 

[IJ.]

It's on a 7Mgte from memory John.

Did you degree the adaptor on the Bell Housing Chris?

 

[disturbed1]

yeah ian - done everything to the book

just thought of somethign that was touch and go and for some reason forgot to check up on it

the splines on the 26 spline input shaft arnt as deep as the ones on the 10 spline. only mm in it but perhpas im running out of spline on the shaft for the clutch plates and they getting jammed up against the flywheel

 

[IJ.]

I'm lost here Chris what exactly have you done?

 

[disturbed1]

swapped to a 26 spline input shaft

this is a bit exaggerated as they not perfectly in the same plane when takign the pic

 

[disturbed1]

problem solved.

hub splines on the disc closest to gearbox are bottoming out on the input shaft splines

1.5mm made all the difference