FE-FC Holden Discussion Forum

i have an m20 4 speed that gets stuck in reverse ,
usually when i gear down from 3rd to second  and then stop like at the lights or in my driveway,
cant comprehend this at all.how could it jump in reverse when ya in second (my shifter is rebuilt?)
my old man reckons that the selector fork is bent.
i had it stored at a rent a space and a removal truck backed into it pushing it forward a foot or so when i went to work on it one day and couldn't work out why the tarp was stuck under the wheels.
when i pulled off the tarp first thing i saw was a squashed passenger door then went to move it it was stuck in reverse
went screaming at the guy that runs the place he says they take no responsibility.he ended up sorta finding camera footage. i got the guy who hit me's phone number but lost it recently,couldn't care less about the guy.i thought i'd fixed it so didn't bother getting money off him,
somehow it has been fine while engineering it etc,
 thank god
 but now it has got stuck again a few times and getting worse.i would work it out myself normally but it's doing my head in driving to nowra from sydney every saturday hoping this or that might fix it.
i've had the box out 4 times already and i think i am seriously over it
PLEASE HELP IF ANYONE HAS ANY REASONS OR IDEAS
THANKYOU

a bloke was telling me something the other day about i think something to do with the reverse light switch being missing in boxes allowing gears to slide forward during downshifting/under braking
sorry this sounds vague but somebody else may be able to elaborate on it

thanks so much ratbox,
it has the terminal for the reverse light switch there,so i guess its there,but that gives me something else to think about.
you may have hit the nail on the head.

Haven't got much time to answer this as off to work in a minute however have you checked the shift linkage bushes.Had an LJ Torana oz 4 speed years ago with gearjam probs and found the shift linkage buses to be non existant.

Fitted new nylon ones and problem fixed.

If linkage bushes are stuffed the box can sometimes not completely change out of gear via shift gate in shifter and then into the next gear selection.Reverse was one of the gears I had probs with at the time.

may not be your problem but something else to look at in addition to Rats idea.

I believe some lube on the linkages also works wonders

thanks to all you guys,
the linkages and everything is tight as .
i have rebuilt everything that moves,or swivels.
the (bad word) i mean thing still gets stuck.i have tried everything, i think.
my mate who loves autos keeps laughing at me.
i will always be a manual man.so i need to fix it to shut him up.
maybe its time to get a three speed,better for drag racing anyways hey.
can anyone help?
PLEASE

Waynos,

I had exacly the same problem, replaced every thing like you did and still had the same problem, but eventually came up with a solution that fixed it for good.........swapped it out for a toyota 5 speed....no problems now and very happy ;D ;D

regards
Weddo

thanks weddo,
i thought that was the solution.
i just didn't want to believe it because i am a tight arse

I had a similar problem a couple of years ago with a M20 4 speed.  I also had a reco shifter but in the finish found the gap in the gate shifter allowed the stick to move out enough to select reverse and second at the same time and lock the box.  You need to adjust the gate alignment 100% and possibly biuld up the keeper that stops the stick from clipping the gate beside it on changing gears.

                                Hope this helps
                                         Frank

fx1975,
appreciate your reply,that is also another thing i have been thinking this week,was gonna adjust reverse on the weekend but didn't go to my parents cause nostalgias was on,i really hope this is the problem,weddos idea is going to be used,
also does anyone know how much a reco 3 speed box is ?

make sure detent spring and ball is fitted to reverse lever very easy to  misplace  if this is fitted reverse cant engage without force on linkage

Had the same problem as Frank with an m20 in an EK(186, holley, extractors), finally got the shits enough to do something about it when my missus got it stuck in reverse and second gear half way accross the main st. of town, you can't even push the car to move it when it happens so the car was stuck there till i drove to town and crawled under with a knockometer to remedy the situation, fitted a trimatic and couldn't beleive how much quicker off the line it was, used to love seeing the look on peoples faces when the old girl left them for dead at the lights.
                                                        Pedro

Waynos,

I had a similiar problem quite a few years ago with a one tonner. I solved by putting an aftermarket shifter in. I will be putting an M20 into my FC and will be using a Speco twin stick shift. These have a seperate stick for reverse and the forward gear selector needs to be in neutral before it can engage reverse.

With this type of shifter I have never known anyone to have a problem with "snagging" reverse when down shifting.

Just food for thought.

Keith

I put one of these in my LC Torrie many moons ago, it transformed the gearbox and was a great conversation piece to boot!