Has a drama with a Recon'd 4 Speed In A HZ (help)

[Clubby 156]

This afternoon me and the old man changed out the gearbox in his HZ Panelvan, that he is doing up.
We put the same type of box (4 Speed M20 i think) in as what came out, it has been reconitioned.
It all went pretty smoothly until we went for the run test. When we selected 1,2,3,4 you can hear the gears change in the box. When we started her up for a drive, no matter what gear we selected, the car would not move, the engine would take up lots of load though.
We could not get reverse selection in as well.
Then put it into neutral and couldnt push it.
It seemed like it was stuck in reverse.
I disconnected all the connecting rods from the sides of the box and bottom of the selector. 1,2,3,4 would move freely, but I couldnt get reverse to move at all. The reverse connecting rod joins on with a bolt that goes into spring tensioned threaded hole.It aslo has a mechanical link to the reverse light switch We didnt have a torque wrench (old man had leant it out) so maybe thinking this was done up too tight???
I also read in the owners manual that each gear selection has to be matched up to the reverse selector plate but couldnt find much more info on how that was done? Guessing this plate is to stop it from been in gear and reverse??

So my question is has any body had this issue before or is there anybody that could shead some light on these questions?

Thanks

[hzholden]

I haven't played around with a M20 for years,my best advise is to post this on oldholden.com.There is a wealth of knowledge on there.
Cheers

[STATIE]

Pretty common thing in the old Aussie 4 speeds - You would have stuffed up the linkage on the reverse selector so it is in reverse full time - then when you select 1-4 the box is staying in reverse as well.

I used to use this as an anti theft measure - had the reverse linkage disconnected from the shifter & would manually put it into reverse when I parked it - anyone trying to pinch it would go nowhere.

Disconnect the rod to the reverse linkage and manually select the reverse linkage the opposite way to it is - then you will be able to drive it normally, then readjust reverse properly & recconect it.

[Smitty]

This afternoon me and the old man changed out the gearbox in his HZ Panelvan, that he is doing up.
We put the same type of box (4 Speed M20 i think) in as what came out, it has been reconitioned.
It all went pretty smoothly until we went for the run test. When we selected 1,2,3,4 you can hear the gears change in the box. When we started her up for a drive, no matter what gear we selected, the car would not move, the engine would take up lots of load though.
We could not get reverse selection in as well..........

hmmmm..... based on my experience ( I build quite a few aussie boxes for the local circuit racers) I think you have one of 2 problems.

either the shifter isnt adjusted properly. It pulls the reverse gear out when you pull the shifter into neutral and if not adjusted properly the shifterr moves
but the gear doesnt ..and then you select first gear and the box is seized as its in both reverse and first. Move the external reverse gear selector lever
(under the car) out of mesh and adjust the shifter properly

or
the reverse gear selector mechanism in the gearbox extension housing has not been installed properly (its a tricky little bugger to get in place properly)
and the sliding block isnt engaged with the reverse gear groove. When that happens you will find that the box has reverse gear selected..ALL THE TIME!
Working the shifter does nothing as the gear isnt connected. The only fix is to pull the extension housing off and refit the reverse selection mechanism..properly

hope that helps

[fx160]

one way of finding out what you probably already know by now
is put it in neutral and let the clutch out , I'm sure the car will reverse
and as said above if it's the linkage you will be able to pull it out of gear by disconnecting it from the shifter
but you will need to make sure there is no load on the gearbox or you won't move it (pt the clutch in while pulling on the linkage)
if you still can't move it then take off the rear extension housing and refit properly

kev

[Clubby 156]

Thanks for the feedback guys.
It look like the reason we couldnt get the reverse linkage to move was because we didnt take the load off the box.
Also when we were putting the other connecting linkages on we did it by putting into 1 with a spanneron the side of the box then connecting it, and putting into 3 then connecting it.
Think we should have put the gearbox gears and shifter into neatral then connected them up.
So we are going to finsh it off tomorrow. Hopefully we can get it out of reverse selection by using the clutch and adjusting it. then connect them all up in neutral.

thanks for you help!!