Re: Selespeed 156 Gear lock Problem
It seems that you cant easily drain the SS fluid, but you can use a turkey baster to suck out the fluid from the tank, as much as possible, and refill with D4, then run the pump and you might have to repeat the "draining" each time refilling with D4, should be very diluted or even gone by two or three fills?
As far as actual hydraulics are concerned (the SS bit of the gearbox) any liquid is non-compressible and will in theory drive a valve. In your case, a pump creates pressurised fluid, and when you click the gearchange lever, the pressurised fluid is used to push or pull other levers to change gear and work the clutch for you etc. The wrong fluid can sometimes damage seals and cause a leak, or stick valves and stop operation. You might have to try repeatedly selecting a gear after flushing the system until the actuators (valves) start to move and work the gearbox parts again.
If theres no leaks of pressure from damaged seals or pipework, then the valves must be stuck and may need removing or replacing (dont know if they are sealed)
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