MautoK
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 posted on 22/6/09 at 11:02 PM |
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Auto box reluctant to change up - Sorted!
I'm on my second gearbox and it's showing signs of going the same way as the first one. 
It's slow to change up, sometimes needing the selector to be moved to persuade it to go into 2nd.
Consequently I'm now getting a bit disillusioned with the whole auto concept and considering going manual.
I already have a type 9 box, flywheel and clutch but no release arm, thrust bearing or cable. The car has no clutch pedal and there's precious
little space to fit one, although I could win some space by moving the footwell side inwards (towards the gearbox) - the auto is about 4 inches wider
than the T9 and the chassis was built to suit.
As I have none of the clutch operating gubbins, the options are:
a. Procure cable/arm/thrust brg and reinstate standard setup;
b. As a. but create pullrod/crank/pullrod instead of cable;
c. Go hydraulic with a concentric slave/thrust brg.
There's a few threads about option c (Saab unit) but mostly a few years old or more. Has there been any advance regarding which parts to use
since then?
The downside of this is that I want a reasonably locost solution and I don't have a machine shop.
Going manual means I'll have to move the gearbox mount about 2 inches forward and extend the engine mounting plates about 3 inches back. And it
looks as if there will be a fight for space between the gearlever and the short tunnel-top cross member. Otherwise I have to get another propshaft
made up 3 inches longer...
Any suggestions, guys & gals?
Cheers,
John.
[Edited on 23/6/09 by MautoK]
He's whittling on a piece of wood. I got a feeling that when he stops whittling, something's gonna happen. (OUATITW/Cheyenne)
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mark chandler
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| posted on 22/6/09 at 11:14 PM |
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Fluid level, run it low and the box goes slushy, overfill and it will hang on to gears. This is quite a fine line, in the car the gearbox and engine
may have been slightly down at the rear, if it sits flat in your car then level on the gearstick will be 1/2 pint to much.
Also is the kick down cable correct, not sure on ford C3 boxes but on zf's if its tight then the gearbox will not like changing up, try
disconnecting and see if it still hangs on.
Regards Mark
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MautoK
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| posted on 22/6/09 at 11:22 PM |
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Hi Mark,
It's an A4LD box and I was quite careful refilling it after my recent engine change. It sits maybe very slightly high at the rear.
The kickdown isn't connected and the k/d lever is in the default position.
I had a look earlier today at the governor in the old box and it looked fine - everything moves freely (but I don't see how it works!)
I'll re-check the level (start, cycle selector 3 times, wait 1 minute, dip) tomorrow...and make sure it's towards the low end of the valid
range.
Cheers,
John.
quote:
Originally posted by mark chandler
Fluid level, run it low and the box goes slushy, overfill and it will hang on to gears. This is quite a fine line, in the car the gearbox and engine
may have been slightly down at the rear, if it sits flat in your car then level on the gearstick will be 1/2 pint to much.
Also is the kick down cable correct, not sure on ford C3 boxes but on zf's if its tight then the gearbox will not like changing up, try
disconnecting and see if it still hangs on.
Regards Mark
He's whittling on a piece of wood. I got a feeling that when he stops whittling, something's gonna happen. (OUATITW/Cheyenne)
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Mr Whippy
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| posted on 23/6/09 at 07:10 AM |
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On many autos there's a duel throttle cable, one to the pedal and one to the gearbox, it’s this second one that is used to tell the gearbox
where the accelerator pedal is. To make the gearbox change up and down quicker and hence make the car more responsive you just reduce the length of
it, i.e. tighten the cable adjuster. If it’s too keen to change through the gears you just slacken it. This is a bit like what goes on with the
sports/snow modes etc it’s just moving the throttle position sensed by the gearbox. If your not using the kick down (don’t know why you would not want
it fitted anyway) and the throttles not set properly it would make the car very lame to drive. Fortunately it’s a 2 minute job to fix ;o)
Having a think about it, are you sure that is the kick down lever? On all my autos the kick down has been an electric switch under the pedal that
shuts a solenoid valve on the gearbox forcing it to drop a gear if the rev range of the engine is suitable to do so. I suspect the lever is infact the
throttle sensor arm and in which case it should definitely be connected. It’s best not to bypass or miss out anything on an auto box as their complex
things and designed specifically to work with everything connected as usual.
do you have a manual for the gearbox? here's one for a reasonable sum -
linky
[Edited on 23/6/09 by Mr Whippy]
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MautoK
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| posted on 23/6/09 at 01:18 PM |
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Well, well - I'd been a bit generous when I filled it. Took about 3/4 litre out and it's much better now.
Good diagnosis, Mark! 
It's not perfect - on a neutral throttle around 50-55 mph it runs in top gear, but drops to third if you so much as breathe on the throttle
pedal. Can live with that for now.
What's more, despite it being quite a warm day it didn't overheat, staying steady just over half scale and the fan didn't come on. I
only did about 12 miles, but the previous engine would have boiled 4 times!
Getting home, the bonnet was too hot to touch in places and could feel a great waft of hot air as I took the bonnet off. So definitely going to chop
some vents now.
For some reason the rev counter has gone on strike. It did this a while back then spontaneously recovered.
But I'm willing to trade a rev counter for a working autobox and no overheating. 
@Mr W:
The kickdown operates by solenoid, triggered by a switch on the throttle cable, neither currently fitted.
John.
He's whittling on a piece of wood. I got a feeling that when he stops whittling, something's gonna happen. (OUATITW/Cheyenne)
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