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1978 Merc 800 will not start

W

Wmayer

New member
-replaced; wire harness, motor starter, solenoid & ignition switch. Solenoid clicks but starter does not engage. When connected directly to battery everything works. Voltage drops at solenoid. Ideas??
 
haventaclue said:
Solenoid is either shot or poor or bad ground/connection,yup even new ones can be dud.
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When you say ground connection, are you talking about the one(s) on the motor itself? For example, there is what appears to be a ground cable going from the starter motor to the aluminum bracing towards the upper front of the engine. The connection for that one on mine is questionable. Could that be causing all this?
 
In your case,yes it could if the core is very badly corroded,give all connections a good clean to shiny.But in Wmayers' case the solenoid is either shot or not grounding properly as when he jumps the starter it works.
 
haventaclue said:
Solenoid is either shot or poor or bad ground/connection,yup even new ones can be dud.

By ground connection do you mean the ground connection to the solenoid or a ground connection to something else? After watching a few YouTube videos with similar engines i noticed that there appears to be (2) wires coming from the top of the motor starter; (1) is the black cable coming from the wire harness and the other appears to be a wire that goes from the same terminal to somewhere on the engine frame. My motor has never had this second wire coming from the starter. In addition to the videos i reviewed, it sounds like Belac0711 motor also has this. Is that 2nd wire from starter to the frame needed?
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There should be a ground and 12v+ from the solenoid to the starter, both usually heavy gauge,4 or 6 awg.12v to the stud low down and the ground at the bracket.Though the starter bolt to bracket should provide adequate ground.
 
haventaclue said:
There should be a ground and 12v+ from the solenoid to the starter, both usually heavy gauge,4 or 6 awg.12v to the stud low down and the ground at the bracket.Though the starter bolt to bracket should provide adequate ground.
Click to expand...

Ok, the starter now engages, but had no spark. I removed the wire from the main harness that is associated with the kill switch so it now starts the engine but the ignition key will not shut-off the engine. I don't believe my year of engine has an actual kill switch.
 
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