Thread: Mystery smoke in cab and bouncy speedo

There is a permanent live wire to the wiper motor on that side, though a short should blow fuses regularly. If the heater matrix has been removed, you could be getting engine fumes or dust off the road coming in through the unblanked hole(s).

The jumping speedo is usually a speedo cable on its way out, though it could also be the square drive inside the gearbox/transfer rounding out. You can pull out the inner cable and regrease it (don't overgrease it, though!!) and the damage may be obvious. I've had the plastic length-locating collar move on a new cable, thus disconnecting drive to the speedo head, but that was an absolute failure, not the jumping mentioned here.

Dan.
69 2A 88" pet4 (still in disguise), 68 2B FC pet6 (still resting quietly), plus 16 other parts/project cars (1xS2, 7xS2As, 8xS3s).

chees will have a look...the heater is still in although disconnected.

Can't help with the smoke, probably oil leaked (or leaking) onto the exhaust system, but the most common source of a bouncing speedo is not the cable, although that does happen, but the speedo drive gear loose on the output shaft of the transfer case.

This gear is only held by the clamping action of the nut on the end of the shaft, and only needs to be very slightly loose to allow it to slip. Disconnect the front of the rear prop shaft to access this nut. Not sure whether it is nyloc or split pin on S3.

John

Thanks John.

A speedo cable badly in need of lubrication will make the needle jump.

A brand new speedo cable lubricated with old fashioned wheel bearing grease will also cause the needle to jump. I managed to achieve that by using a bit of the grease that my BIL used for the wheel bearings of his T Model Ford.

Use a lighter grease.