AndyStobbs
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As title really, more info if I get a hit!
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Lawnmowerboy
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Grandad worked for them and Anglo Swedish in the 70S and 80s
AndyStobbs
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Ok then, maybe you can shed some light on this. I was asked to look at one earlier today, an A25 I think, 6x6. Basically it wouldn't move, gearbox worked ok and selected gears but the drop box wouldn't transmit drive. Some other mechanics had already had a look and concluded it was an electrical issue, hence my involvement.
What I found was a pneumatic cylinder sat on the rhs of the drop box had become jammed against a lever projecting from the drop box casing. The actuator was mounted on a clevis pin, and would've been free to pivot in an earlier life before it all got rusted solid. The actuator rod looked like it was at one time connected to this lever. By means of a rose bush I assume.
Anyway most of the linkage was long gone with just a stub of thread left on the actuator and a hole in the end of the lever. Once I had separated the two, the lever could be moved by hand between two deffinite positions, I'm guessing its a form of dog clutch or some other means of meshing two parts together as it helped to rotate the input shaft to engage/disengage the drive.
With this lever now in the upward position drive through the drop box was restored. I spent a while trying to discover which lever/button in the cab controlled the actuator in question but after half an hour had to admit defeat, I lost one of the air pipes somewhere under the front bulkhead, but did trace the other to a small push button knob on the floor on the left of the brake pedal, however depressing said button had no effect on the actuator.
Clearly its some form of clutch, but what originally would have been used to control it?
Also the arm coming out from the drop box had a tang on it, which again in a former life looked like it would've activated a microswitch (i assume), anyone know anything about the switch, or indeed the clutch?
What I found was a pneumatic cylinder sat on the rhs of the drop box had become jammed against a lever projecting from the drop box casing. The actuator was mounted on a clevis pin, and would've been free to pivot in an earlier life before it all got rusted solid. The actuator rod looked like it was at one time connected to this lever. By means of a rose bush I assume.
Anyway most of the linkage was long gone with just a stub of thread left on the actuator and a hole in the end of the lever. Once I had separated the two, the lever could be moved by hand between two deffinite positions, I'm guessing its a form of dog clutch or some other means of meshing two parts together as it helped to rotate the input shaft to engage/disengage the drive.
With this lever now in the upward position drive through the drop box was restored. I spent a while trying to discover which lever/button in the cab controlled the actuator in question but after half an hour had to admit defeat, I lost one of the air pipes somewhere under the front bulkhead, but did trace the other to a small push button knob on the floor on the left of the brake pedal, however depressing said button had no effect on the actuator.
Clearly its some form of clutch, but what originally would have been used to control it?
Also the arm coming out from the drop box had a tang on it, which again in a former life looked like it would've activated a microswitch (i assume), anyone know anything about the switch, or indeed the clutch?
the snooper
getting older by the day
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AndyStobbs
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Will have to wait until I'm on the pc in work to view it, but thanks for the link.
seriesonewelder
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"but did trace the other to a small push button knob on the floor on the left of the brake pedal, however depressing said button"
The button on the floor activates all the diff locks, the exhaust retarder is operated by the left pedal (we have an ancient A25C at work).
"Clearly its some form of clutch, but what originally would have been used to control it?
Also the arm coming out from the drop box had a tang on it, which again in a former life looked like it would've activated a microswitch (i assume), anyone know anything about the switch, or indeed the clutch?"
Sorry I cant answer that, but if I remember I'll look tomorrow, I've bled dumpers and helped change alternators but not learnt much else.
The button on the floor activates all the diff locks, the exhaust retarder is operated by the left pedal (we have an ancient A25C at work).
"Clearly its some form of clutch, but what originally would have been used to control it?
Also the arm coming out from the drop box had a tang on it, which again in a former life looked like it would've activated a microswitch (i assume), anyone know anything about the switch, or indeed the clutch?"
Sorry I cant answer that, but if I remember I'll look tomorrow, I've bled dumpers and helped change alternators but not learnt much else.
