SLROC Forum

Any ideas drives in 1 and 2 and reverse but when placed in 3 or 4 just does nothing as if not in gear no noise no crunch etc just goes in gear lift up clutch and nada?

Unless you're good mechanically, swap the gearbox.

Relatively cheap to do..... a day's work.... and definitely worth it.

Could be that your selector fork bits are missing (or that the selector is not moving witht he gearstick) and that it will not change the sycro forward or back.

The selector fork for 3rd,4th is separate from the 1st,2nd and reverse ones. They are all selected by a rod and pin arrangement. the pin does the pushing and pulling of the top end of the fork. as you move the gearstick left or right the pin selects different forks.

You will possibly have to take off the gear housing and inspect the forks for wear.
Could also be that the selector ring has exploded and is in bits at the bottom of the gearbox.

check the oil and plug, if the oil is full of glittery brass coulourd bits then if would be fork wear, if the plug magnet is full of iron filings then some ring or spline or grear teeth are getting worn.

hope this helps.
 

Change the gearbox and keep the series going...........

Well I haven't got the time so I took it to strathearn engineering today, very slow drive in 2nd gear and the drivers door open
So we will see how they get on with it hopefully its a cheap ish fix and will pass a mot if not its time for the scrap heap 
Shame cos I was growing to enjoy driven it ,

Ok so got it back from strathearn today
And after driven her I really don't want to scrap it

So I took the gearbox selector apart and can see the synchromesh for 3 and 4 gears 12 and reverse work great selector fork is ok and the detent springs apper to be intack when in 3 or 4 you can see the synchromesh turn but no drive can anyone help to what might be the problem to save it from scrap?

I had this problem once.  I opened the top of the box, inside the 3rd/4th synchro hub there are 3 flat "W" shaped springs, one of the three had split in the middle and the two ends had dropped into the gears preventing 3/4th gear selection.  I took the broken parts of the spring out and the gearbox ran fine for years with 2 instead of 3 springs.  Got to be worth a look before you start pulling gearboxes out.

ZD

I've opened it up and the springs seem to be intact, and the synchromesh moves when selected rod is moved into gear but spin with moving the car when in gear? Arrrrrrrr