We have to straighten out the words here first to be sure we don't have a misunderstanding. Words are all we have to analyze. We can not see or touch the problem.
Here in the USA we call the "minus" side of a circuit, negative. Also referred to in the USA as ground. We call the other side "Positive".
Also please use the term "wire" for a wire..... and "cable" for a very large wire like the battery cables.
Please ALWAYS use a modifier in your explanations..... don't say "the minus cable slipped out of the connection"...say the
ground wire of the
fuel pump slipped out of it's
crimped on terminal that was
attached to the chassis with a sheet metal screw.
We don't want to misconstrue what you did or found or corrected. Otherwise we will go off in the wrong direction (which may happen anyway).
So.....QUESTIONS:
1. "As far as I know, one should'nt see sparks coming out of a minus cable - right?" Was the spark coming from the ground terminal end of the fuel pump wire which is attached to chassis metal with a screw?
2. "So I disconnected the minus cable from the battery, and measured between the minus pole and the loose cable." So you took the negative battery cable off it's battery post and measured between that post and the battery ground cable that you just took off or..... did you measure from the post to the fuel pump loose screw end?
3. Do you have a relay in the fuel pump circuit?
Can you check to see, that when key/ignition is off, if there is 12V coming to the fuel pump positive supply wire/terminal?
*I can better help you after these are answered.
Obviously the 41 has had a 12V conversion. Was this done by you? and when was it done? Have you done any wiring anywhere recently?....or replaced any components?
Phil is heading where I am thinking of heading, once I get clarification and the test.
* You should not see voltage between the post and ground. Something is "on" that should not be "on". There is resistance somewhere, creating a load. The battery is trying to service that "load"/resistance. You are doing something similar to a voltage drop test. Parasitic draw test. Do the same test but set meter to amps.
I seems like a stuck relay/VR, bad fuel pump or bad ignition switch....or you recently miswired something....Carl's backfeed.
Does it all work Now? Starts? Runs? Fuel pump not clicking or humming?
\What motor is in the 41? Is the 41 a Chevy? Alternator or generator?
