12 volts at coil?

[bobbyb]

hi all
i have a old mercruiser and was playing with the multymeter today and found i have only 7 volts at the + sideof the coil. removed wire an tested to get 11.5 volts,
replaced wire 7 volts again. is this normal? any help would be great.
cheers..............>:(

[backlash08]

does that system have a ballast resistor and points, many older ignition system run a ballast resistor (~8V at run to the points and 12 V at start), this allows for stronger spark for starting but less spark when running to allow the points to last longer - not saying that this is your problem but it may be.

worth checking this, also are you checking the same wire and with the key on run and start position

cheers - Craig

[bobbyb]

thanks clee. it did have points butt just converted to electronic. dont think it hase ballast resister.
rob...........

[TheRealAndy]

IT the motor working ok? Where you measuring with a digital multimeter? Its probably perfectly normal. What you are probably measuring is leakage currents through the coil itself, they mean nothing.

[backlash08]

when you converted to electronic did you bypass the resistor? (might look like a small ceramic rectangle block with wires running to either end) and have you checked voltage with key in start and run position (not, you may need to disconnet coil lead when on start position so that engine doesnt fire - Craig

[bobbyb]

sorry guys ,had a phone call (bludy rellies)
have never sean a resister and had moter out a couple of times. moter pures like a kitten. bean out since fitting the new ignition and run nice.
maybe its nothing but i would feel beter knowing i got max performance .
thought i might use my ignition wire to operate a realay and run a solid wire from a nother source? what do u think?................

[backlash08]

cant realy advise how to solve without understanding if you actually have a problem, worth going over all of the paperwork that came with elec igntion conversion, as you say might not have a problem but also might have - try checking voltage at -ive side of coil, if it is 12 V then you are probably ok

[bobbyb]

thanks clee.
will ring my mercruiser guy today to see if i should have 12 volts at coil at all times.
cheers rob..............