1985 volvo penta 260A

[buddycorn]

Having a problem cranking my 1985 260A. I am getting fuel and it appears that it is firing since it acts like it wants to crank but when I let go of the key it may turn over a couple of times more but will just die out. Good fuel and fuel filter and pump. Plugs are wet when pulled. Plugs were tested for firing and all appear to be firing. Puzzled.

 

[el_pescador]

Coil? Distributor cap/rotor (moisture inside)? Ignition wires (corrosion on leads terminals)? Timing is off a few degrees too many? Or maybe the choke is not working and it is stuck open? Or have you flooded the intake manifold and cylinders with too much fuel?

I would start eliminating one by one some of the above possible causes.

 

[RicardoMarine]

...................... but when I let go of the key it may turn over a couple of times more but will just die out.

This may be a clue for what I'm posting here.... not sure, but worth a shot.
#1
The factory ignition system may have what some call a start by-pass circuit.
IOW's.... while the starter motor is being energized, full current is present at the igniton coil (not resisted current via a ballast resistor).
When you let off on the key, this by-pass circuit drops out.
Unless someone has installed an electronic ignition distributor, this By-Pass is likely still connected!
If the main ignition circuit is faulty (key switch, hull harness, engine harness, ballast resistor, etc.) this may explain why the engine dies once you let go of the key switch, and are out of the start by-pass mode.


Using a process of elimination, start by taking your VOM or test light, and see if your ignition coil receives power with key on only.

See if you have power at the "Ign" terminal of the key switch and to the purple wire that leads to the harness.
You will have a harness connection under the instrument panel somewhere.... check this too.

You also have an engine/hull harness connector somewhere on the inside of your transom..... probably Stdb side of engine.
It will be white plastic with a black boot covering it up.
These are prone to contact failure due to moisture/corrosion.
Pull this apart.... push back together several times after spraying a corrosion blocker into the connectors.
Look for any burned connectors.

A good P of E will work for you!
I'd probably start at the helm and work my way back after having first explored # 1 above.

.

 

[buddycorn]

Thanks. Very grateful for the information.