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C.Jackson · 02-15-2001, 11:58 PM

to further your diagnosis....with a voltmeter.... have someone crank the engine and take a voltage reading ON THE POS STUD itself, not the terminal (holding your negative probe on the neg STUD). Then take the same reading on the terminal not the stud. Voltage difference? No? do the same on the negative post (holding the pos probe on the pos STUD), then the terminal. Difference? voltage drops mean bad connections. If no voltage drop....do the same test at the starter. first on the positive terminal, then the pos stud (with the neg probe on the neg bat STUD). if nothing, hold your neg probe on the starter and try it (with the pos probe on the pos STUD). Then on the block and try it. The bottom line......Ohm's law proves amperage will increase to overcome a voltage loss, hence smoking wires and burned up parts. generally, the point of voltage drop will produce the visual signs like smoke and melting. Find that voltage drop and you'll fix the prob. Incidentally...if your voltage crashes right on the bat posts you have a weak or shorted battery. 8 or 9 volts is fairly common during cranking...lower than that you definitely have a problem. Sustained voltage during high demand depends on battery rating. An 8-D battery might fall to 11 volts but a honda battery will fall to 4 volts. It's all respective. just a sidenote.

------------------
C.Jackson
Juneau, Alaska
Dba AC-DC Electrical and Equipment Repair
'81 crew cab dually..5 ton gear, air, 10sp, 3208..if it aint a CAT it must be a dog
'87 K-5..454..9"..38.5's (the wife's)
'72 C-10..427 tall..FAST (the wife's)
'49 Dodge 5 window..413 max wedge..VERY FAST
'79 Dodge one ton..440..15"..38.5's
'84 S-10..350 auto (the wife's)

02-15-2001, 11:58 PM	#10
C.Jackson Registered User Join Date: Jan 2001 Location: Juneau, Alaska Posts: 51	to further your diagnosis....with a voltmeter.... have someone crank the engine and take a voltage reading ON THE POS STUD itself, not the terminal (holding your negative probe on the neg STUD). Then take the same reading on the terminal not the stud. Voltage difference? No? do the same on the negative post (holding the pos probe on the pos STUD), then the terminal. Difference? voltage drops mean bad connections. If no voltage drop....do the same test at the starter. first on the positive terminal, then the pos stud (with the neg probe on the neg bat STUD). if nothing, hold your neg probe on the starter and try it (with the pos probe on the pos STUD). Then on the block and try it. The bottom line......Ohm's law proves amperage will increase to overcome a voltage loss, hence smoking wires and burned up parts. generally, the point of voltage drop will produce the visual signs like smoke and melting. Find that voltage drop and you'll fix the prob. Incidentally...if your voltage crashes right on the bat posts you have a weak or shorted battery. 8 or 9 volts is fairly common during cranking...lower than that you definitely have a problem. Sustained voltage during high demand depends on battery rating. An 8-D battery might fall to 11 volts but a honda battery will fall to 4 volts. It's all respective. just a sidenote. ------------------ C.Jackson Juneau, Alaska Dba AC-DC Electrical and Equipment Repair '81 crew cab dually..5 ton gear, air, 10sp, 3208..if it aint a CAT it must be a dog '87 K-5..454..9"..38.5's (the wife's) '72 C-10..427 tall..FAST (the wife's) '49 Dodge 5 window..413 max wedge..VERY FAST '79 Dodge one ton..440..15"..38.5's '84 S-10..350 auto (the wife's) __________________ C.Jackson Juneau, Alaska Dba AC-DC Electrical and Equipment Repair '81 crew cab dually..5 ton gear, air, 10sp, 3208..if it aint a CAT it must be a dog '87 K-5..454..9"..38.5's (the wife's) '72 C-10..427 tall..FAST (the wife's) '49 Dodge 5 window..413 max wedge..VERY FAST '79 Dodge one ton..440..15"..38.5's '84 S-10..350 auto (the wife's)