Reply to post:

"What should we do if the printer is smoking?"

We[1] have a Morris Minor car - converted to negative earth and with an alternator fitted. At one point, the petrol pump failed (they last, on average, about 10 years).

So, being a good husband, I located, ordered and was delivered, a new one. That weekend, I took off the old one and fitted the new one - not a difficult job since the pump is easily accessible on the back bulkhead of the large-and-fairly-empty[2] engine compartment - although you do have to make sure that you don't let the petrol pipes drop to the floor since all the petrol in the tank then syphons itself out under the car..

New petrol pump duly fitted, petrol pipes reconnected (the right way round) and all the wires mostly done up firmly, I asked my wife to fire up the car to check the new pump was working. After a few seconds, I heard the pump ticking away, thus proving it was working. Then my wife stuck her head out of the side windows and asked me whether smoke should be coming out from under the dashboard..

One hurried turn-off later, I discover that Morris Minors are *very* sensitive to how well the earthing is done and that not doing up the earth connection tightly enough will draw enough current to make the old rubber-and-fabric-covered wiring get hot enough to smoke..

We cleaned the wiring up, applied liberal amounts of insulating tape and duct tape where appropriate and that petrol pump is still resident, ticking away and delivering go-juice to the mighty 1098cc A-series engine[2].

[1] Nominally "we". In practice, "my wife has".. I drive a car with modern luxuries like power steering and proper braking. And a working heater..

[2] Which has now done well over 115K miles. And has an in-line fuel catalyst module that uses tin as an anti-knock agent. It's entirely appropriate for someone who had an ancestor that was the captain of a Cornish tin mine now drives a car partly powered by tin..