OK, i’ve been driving manual 16 speed DAFs for a while now. I’ll be honest and say that beforehand I was very much accustomed to having an auto. Anyway, been getting on no problems but every so often when I try and pull off, the thing just will not go into gear. Turning the engine off and restarting always solves the problem, but I was wondering what the cause is and if there is any better way of rectifying it. Is it normal?
It usually happens when starting off, but has occasionally happened to me at a set of lights.
rob22888:
OK, i’ve been driving manual 16 speed DAFs for a while now. I’ll be honest and say that beforehand I was very much accustomed to having an auto. Anyway, been getting on no problems but every so often when I try and pull off, the thing just will not go into gear. Turning the engine off and restarting always solves the problem, but I was wondering what the cause is and if there is any better way of rectifying it. Is it normal?
It usually happens when starting off, but has occasionally happened to me at a set of lights.
Flick the range change selector (not splitter) into the other box and then back again, then retry. That usually clears it.
Agree with above. I’ve driven Daf 8, 12 (the Eaton one fitted to Foden Alphas) and 16 speeds and have experienced “air lock” with all of them. I reckon the 12 and 16 speed 'boxes were better than the 8s though.
rob22888:
OK, i’ve been driving manual 16 speed DAFs for a while now. I’ll be honest and say that beforehand I was very much accustomed to having an auto. Anyway, been getting on no problems but every so often when I try and pull off, the thing just will not go into gear. Turning the engine off and restarting always solves the problem, but I was wondering what the cause is and if there is any better way of rectifying it. Is it normal?
It usually happens when starting off, but has occasionally happened to me at a set of lights.
I presume you try pressing the clutch a few times and aren’t just keeping it down once?
As said previously just flick the range back in to high then low…Generally happens when you drop in to low box ,the range just hasn’t went al the way in to low ,and it then blocks any gear selection
norb:
As said previously just flick the range back in to high then low…Generally happens when you drop in to low box ,the range just hasn’t went al the way in to low ,and it then blocks any gear selection
I’m guessing that’s what he’s referring to by his description of the problem, but I’m not entirely sure. I seem to recall having a CF ZF-16 many years ago which was just a pain to get into some gears and it wasn’t anything to do with the range change. Think it was something in or attached to the gearbox that had worn or come out of line and needed replacing - it was absolutely fine after that and wasn’t too expensive either from what I recall. You work on them so probably know what I’m referring to.
rob22888:
OK, i’ve been driving manual 16 speed DAFs for a while now. I’ll be honest and say that beforehand I was very much accustomed to having an auto. Anyway, been getting on no problems but every so often when I try and pull off, the thing just will not go into gear. Turning the engine off and restarting always solves the problem, but I was wondering what the cause is and if there is any better way of rectifying it. Is it normal?
It usually happens when starting off, but has occasionally happened to me at a set of lights.
Flick the range change selector (not splitter) into the other box and then back again, then retry. That usually clears it.
this ^^^^^^ mine does the same thing and this clears it for me low/high range and back again
norb:
As said previously just flick the range back in to high then low…Generally happens when you drop in to low box ,the range just hasn’t went al the way in to low ,and it then blocks any gear selection
I’m guessing that’s what he’s referring to by his description of the problem, but I’m not entirely sure. I seem to recall having a CF ZF-16 many years ago which was just a pain to get into some gears and it wasn’t anything to do with the range change. Think it was something in or attached to the gearbox that had worn or come out of line and needed replacing - it was absolutely fine after that and wasn’t too expensive either from what I recall. You work on them so probably know what I’m referring to.
At a guess what you are referring to was probably the plunger in the Neutral valve failing …It was a small cylinder in the valve with a ball bearing that would fail or the cylinder would seize,which would cause excessive effort to get a gear
norb:
As said previously just flick the range back in to high then low…Generally happens when you drop in to low box ,the range just hasn’t went al the way in to low ,and it then blocks any gear selection
I’m guessing that’s what he’s referring to by his description of the problem, but I’m not entirely sure. I seem to recall having a CF ZF-16 many years ago which was just a pain to get into some gears and it wasn’t anything to do with the range change. Think it was something in or attached to the gearbox that had worn or come out of line and needed replacing - it was absolutely fine after that and wasn’t too expensive either from what I recall. You work on them so probably know what I’m referring to.
At a guess what you are referring to was probably the plunger in the Neutral valve failing …It was a small cylinder in the valve with a ball bearing that would fail or the cylinder would seize,which would cause excessive effort to get a gear
Don’t think it was that. Thought it was something called a gear selector thingy on the box where if it was worn or out of alignment it made it nigh on impossible to get it into any gear. Might be thinking of a different marque, was a long time ago now.
Depending how old it was ,if it had servo shift which is attached to the base of the turret,that can cause issues with the slector shaft ,another good one was the bearing on the bottom of the gearlever on 85s…Generally with a turret fault you had the neutral valve ,a couple of detents ,and worn bushes that supported the shaft in the turret…Difficulty getting 1st/2nd was generally down to the gate protection valve hydraulicing ,or the pin below the switch on the range sticking…There is also a small support on the selectors that wear ,(been modified now though) that wears and and causes difficulty generally again with 1st and 2nd,you would generally have grinding when selecting 2nd ,often blamed on syncros…I fact the wear on the selector forks actually meant it was trying to select 2nd and reverse at the same time ,the grinding being reverse…Phew that’s m out of ideas
Norb, I had the bearing go on a 12 speed Eaton on the Alpha I drove. it was a very interesting experience trying to change on Birdlip Hill, considering two of the gearbox mounts sheared shortly after…
norb:
Depending how old it was ,if it had servo shift which is attached to the base of the turret,that can cause issues with the slector shaft ,another good one was the bearing on the bottom of the gearlever on 85s…Generally with a turret fault you had the neutral valve ,a couple of detents ,and worn bushes that supported the shaft in the turret…Difficulty getting 1st/2nd was generally down to the gate protection valve hydraulicing ,or the pin below the switch on the range sticking…There is also a small support on the selectors that wear ,(been modified now though) that wears and and causes difficulty generally again with 1st and 2nd,you would generally have grinding when selecting 2nd ,often blamed on syncros…I fact the wear on the selector forks actually meant it was trying to select 2nd and reverse at the same time ,the grinding being reverse…Phew that’s m out of ideas
I reckon it was one of those! It was apparently “an easy fix” when it went on mine and it was like driving a new truck afterwards.
Hiya…right at the bottom of the cluck travel is a clutch brake that stops the gears spinning so you
can select a gear easy (there,s a lot going on inside a 16 speed gearbox) sometimes the gear dosn’t
stop where the teeth line up and two faces meet. just trying the clutch again or changing the high
low will let one gear move a little so the teeth line up and go into mesh easier…i had the same 16
speed for 13 years…wounder how many gear changes i did in the time
John
3300John:
Hiya…right at the bottom of the cluck travel is a clutch brake that stops the gears spinning so you
can select a gear easy (there,s a lot going on inside a 16 speed gearbox) sometimes the gear dosn’t
stop where the teeth line up and two faces meet. just trying the clutch again or changing the high
low will let one gear move a little so the teeth line up and go into mesh easier…i had the same 16
speed for 13 years…wounder how many gear changes i did in the time
John
Hi John ,the clutch brake would be on an eaton box ,the zf 16 speed has nothing like that …the autos have a brake in the box
Cotswoldcrunch:
Norb, I had the bearing go on a 12 speed Eaton on the Alpha I drove. it was a very interesting experience trying to change on Birdlip Hill, considering two of the gearbox mounts sheared shortly after…
I’m a jock and what where you doing up Birdip Hill Doesn’t that place have a reputation
Problem with failed bearings is the shaft then is basically floating up and down and back and forth
Thought it was something called a gear selector thingy on the box where if it was worn or out of alignment it made it nigh on impossible to get it into any gear. Might be thinking of a different marque, was a long time ago now. 
