Really need electrical help force 70 !

[bigdog99019]

Have a force 70 3 cyl. Wont start. Turns over. Has good cranking voltage etc. Took stator off and looked at it. Looks new but it is not a red one. Cant believe it could be bad. Boat would run after prolonged cranking with battery charger attached last year. Can anyone tell me what kind of readings I should get on the stator, trigger, coils. etc. What is the chance of the cdi being bad ?

 

[roscoe]

Re: Really need electrical help force 70 !

You really need to get a repair manual, as there is way too much tech info and troubleshooting tests to try to type here.<br />The factory manual is available from Mercury dealers. Or get the manual by Clymers for Force motors, its pretty good.<br />I don't have my manuals with me, so I can't give you any numbers.<br /><br />Does battery stay charged when motor is running?<br />check voltage across the battery terminals when running.<br /><br />Does the tach work?<br />If you are not getting 14+volt across the battery, or 5v to the tach, then your rectifier is likely the problem.<br /><br />Stator test is a simple ohm resistance test.<br />The stator can supply voltage to the rectifier, but fail to supply voltage to the switchbox and trigger. <br />Could be trigger, stator, switchbox/cdi, coils.<br /><br />You don't say if you have checked for spark strength or the compression. I would do that first.<br /><br />I have a 70hp '95 with the original black stator also, but i have a spare red one, for when that day comes.

 

[bigdog99019]

Re: Really need electrical help force 70 !

Ok here it is. I have the stator out of the engine. It is model #398-8778a16. It appears to look new. I think this is a mercury part# and looks to have been replaced. Has 2yellow 1red,1blue 1black wire. I assume the yellows are for the charging circuit. I show about 856 ohms accross the red and blue with the meter on 2000ohms. The two yellows seem to have continuity. Does anyone else have any other ideas. I did remove the kill wire. No change. does anyone know how to check any of the other parts ?

 

[choskin]

Re: Really need electrical help force 70 !

Clymer manual says 70Hp Force all motors use thunderbolt ignition system.<br />Stator resistance test is abreviated as follows<br />Red and Blue wires (low speed charge coil)<br />the resistance of stator part number <br />398-8778A10,A26 or A29 will be 3600-4200 ohms.<br />The resistance of upgraded stator part number 398-9873A24 will be 1100-1600 ohms.<br />Testing between the Red and Black(ground) wires <br />(high speed charge coil)<br />398-8778A10,A26 or A29 will be 90-140 ohms.<br />398-9873A24 will be 30-35 ohms.

 

[choskin]

Re: Really need electrical help force 70 !

You say the boat would run after prolonged cranking.<br />My 1991 70HP Force suffered from hard to start when cold. It would take almost all a fully charged battery to start.<br />The fault turned out to be the fuel primer solenoid(sometimes referred to as the choke)<br />when the ignition key is pushed in, the primer solenoid operates, dumping fuel directly into the inlet manifold.

 

[tinbender2u]

Re: Really need electrical help force 70 !

think u r going the wrong way it cranked last year but was hard to start // stator is for charging the battery / there is a trigger ring under the flywheel to but think u need to put it back together ansd start over / got spark put screwdriver in the spark plug wire / getting fuel /choke working ???

 

[12Footer]

Re: Really need electrical help force 70 !

How many volts did you get from the stator when you turned the motor over?<br />It could be the trigger,or something as simple as a shorted kill wire.<br />You should get continuity accross both sets of wires. Gotta run, but will post cranking volts after werk (gotta look those values up in the force bible).