What the previous owner should have done if the right choke is U/S is.
Disconnect the 12v wire (not that leaving it connected wouldn't make any real difference)
Slacken off the 3 screws holding the choke to the carb.
Rotate the choke until the choke flap is vertical
Tighten up the 3 screws
That would disable the choke completely. In reality you should be able to start a T25 with no chokes at all, unless it is really cold, just by pumping the throttle.
When you say the van starts fine does it fire up and idle without you using the throttle?
When I start my van I push the pedal to the floor and let it up. Turn the key without my foot on the pedal and the engine fires and runs at +1000 RPM. After a few seconds as the revs start to rise, I tap the pedal to disengage the chokes and the idle drops to about 800 RPM. If I don't tap the pedal the revs start to climb as the engine warms up.
Having a faulty choke isn't a big issue if its disabled properly, after all its only supposed to work for a minute or two when the engine is cold. The bigger issue is if the carb setting have been messed with when the previous owner tried working around the choke problem. Getting the carbs set and balanced isn't difficult if you do it systematically. Have a read of this link it'll make everything a lot clearer.
http://www.ratwell.com/technical/DualCarbs.html" onclick="window.open(this.href);return false;
I'd still be surprised if the only problem is the carbs. Losing 20 mph off the top end is a serious lack of power or the brakes are dragging. Someone hasn't stuck a 1.6 engine in it have they?
2ltr Aircooled CU with twin Solex's & originally a 009 dizzie, but now back to standard.
