resistance wire ? on mercruiser 470 1985 190hp

[shark bite]

470 mercruiser boy have I learned alot in the last two years and now have another issue...boat cranks and immediately shuts off hmmm...so off to napa I go and get some points and condensor (sierra made), thinking condensor problem by the blue points and the sudden crank and stall problem...

after numorous attempts and cap removal noticed would crank and run if I went from battery straight to coil ,,,but only idle try clearing it up with a little throttle and shake shake shake oh no then spit through carb and stall...

went through some wiring diagrams and found a resistance wire from coil to carb choke checked this out only to find its broken off and just dangling behind the four barrel but in a double splice connector that is supposed to go to carb choke...does this need to be intact on the choke to function properly and could this be my problem? all input appreciated....thanks in advance

 

[Don S]

Re: resistance wire ? on mercruiser 470 1985 190hp

It doesn't have to be hooked to the choke to work, but it does have to have a good connection in that splice (purple wire), and the resistor wire needs to work.
With the key in the run position, you should have power to that choke wire and on to power to the coil through the resistor wire.

 

[shark bite]

Re: resistance wire ? on mercruiser 470 1985 190hp

thanks for the input Mr. S I am going out now to check this out I am not happy with the jumper wire in there to make it work...

 

[shark bite]

Re: resistance wire ? on mercruiser 470 1985 190hp

OK heres what I just did

cut the wires at the choke , and made a joint, get a proper spade tomorrow but for now making a good connection..

at the battery had 12.78volts

at the choke connection had 12.15

at the + coil side had 10.23

at the - coil side had 7.50

also have replaced PURPLE/YELLOW wire from auxillary solenoid to coil positive with new one....did this as new starter went in and solenoid also made all new connections and used mercury triple guard grease on spades before crimping.....


biggest puzzle to me is boat ran fine put over a hundred miles on it two weeks ago and try to crank it weekly and a week ago this problem occured while trying to crank ...It will seem to start then shut down...I bypass the wire from the solenoid and come straight from the battery she will crank but only idle ....

got new points and condensor
coil and wires and plugs
new starter and solenoid
new wire from solenoid to coil
and that is last two days seems more I do more it needs lol

since May have new 4" heat exchanger, camshaft redi sleeves,thermostat,oil
change,riser gasket,impeller lower unit and changed lower unit fluid, drained fuel tank and put in water seperator,shift cables,new gauges,alternator conversion,new power steering lines, and added some new grounds to dash and to motor,,added new battery to cabin for electronics only..Then started on cosmetics and this happens wouldn't it be easier to just build a boat from scratch

 

[shark bite]

Re: resistance wire ? on mercruiser 470 1985 190hp

wont run unless jumper is installed from battery to coil any ideas what to check or maybe a process of elimination

 

[shark bite]

Re: resistance wire ? on mercruiser 470 1985 190hp

when I fix this I will let the readers know what the problem was so if it were to happen to anyone else maybe I would be of some help

 

[nola mike]

Re: resistance wire ? on mercruiser 470 1985 190hp

The running at idle thing is weird. Doesn't sound ign related. No fuel probs? Choke ok? Compression?

 

[stonyloam]

Re: resistance wire ? on mercruiser 470 1985 190hp

at the battery had 12.78volts

at the choke connection had 12.15

That 1/2 volt drop there is a little strange. Should be the same as battery. Could be a bad connection somewhere that is limiting the current flow to the coil, even though the voltage is close to where it should be. Try this: Jumper directly from the battery to the choke end of the resistance wire. See if that helps. You could also check your purple wire connections from the ignition switch, to try to pinpoint the voltage drop. Good luck.