1995 4.3 GS volvo penta cranks itself with no key!

[HughV]

Out for a few hours fishing today. Idling, pulling in fishing gear and hear a 1 second circular-saw-strikes-metal sound. (As issues continued, realized later it was the starter engaged for a bilp, no touch of the key!) Noise started up again after a few minutes of running. Stopped, didn't see anything amiss, re-started and 15 sec later had smoke coming from engine compartment. Alternator belt was smoking, figured its bearings were siezing, causing belt smoke and noise. (later figured out it was probably being overloaded and fairly loose belt (bearing conserving) caused smoke, read on) Figured 2 new batteries, 15 min back to doc, decided to cut alternator belt. Ha! lost fuel pump when running. Start->run 20 sec on fuel in carb from start circuit drive on fuel pump, ->stall. (figured this out later). Anyway monkeying with wiring around engine, nothing, but some clicking of fuel pump and starter engagement (fortunately hands not in contact with belts when this happened!) with key off! It actually cranked over! Turned off battery switch and called for a tow. Wiring diagram is home :^( How is power intermittently getting to the starter (some battery to solenoid short, inside original alternator or old rusty starter?), how is alternator being overloaded (trying to power starter while engine is running?) Another guess: one or more of those fuel pump circuit diodes for start and run power is shorted (still need to make the bat/solenoid connection)? Anybody seen this? Have a charging/starting/fuel pump wiring diagram handy? Is there a relay between the key switch and the starter solenoid? Thanks, Hugh

 

[wired1236]

Re: 1995 4.3 GS volvo penta cranks itself with no key!

Just a thought but I would suggest replacing the ignition switch. They often go bad and do some wierd things in my experience. Very possible it's something else but It's a cheap & easy part to replace and IMO, if it's the original switch, CAN BE pretty flimsy.

 

[jgresham75]

Re: 1995 4.3 GS volvo penta cranks itself with no key!

Here is a suggestion. When the solenoid is engaged, the plunger inside presses a button in the end of the chamger that completes the circuit to turn the starter motor. The solenoid plunger has a return spring that keeps it away from the button when not engaged. It is possible that the return spring is broken/rusted and therefore the solenoid is sliding around, thus engaging the starter motor sporatically. What makes me think this is your description about the 1 second blip of the starter and the sporatic engagements. If you just happen to rock in a specific direction, the solenoid plunger could have slid to the button. Just a thought.