85ESL75E No spark

[Bullie]

A friend recently picked up a pontoon boat with 75 model 85 hp. It has 120 lb compression on all 4 cylinders and the starter is strong. No spark on any cylinder though. He stripped down most of the boat to make a duck blind and, I am guessing, may have lost/cut the man overboard switch. There is a lanyard for it laying on the deck so I assume it had one. How would I find out which wires are on that kill circuit? I again am guessing that would be the reason for no spark on any cylinder. He did have voltage from the stator to the connection at the rear of the motor.

 

[gm280]

On that engine, you have a timer base and a power pack that produces the ignition spark along with the coils. So the stator output has nothing to do with the ignition system. The stator is a 6 amp setup to charge the battery only. So check to see if the spark coils are getting anything to fire them. If so, you have a few bad coils...which I really doubt. If your coils aren't being fired, look at the power pack or timer base...

 

[sutor623]

Make sure you don't have a short in your kill switch wire going into the power pack (black and yellow). When this wire is grounded it will prevent any spark, which is why when you turn the key to off the motor shuts down. And like you said, there is a kill switch on the control box, that lanyard has a black plastic piece that slips into the kill switch, make sure it is in there.

 

[Bullie]

Thanks guys. I think y'all are heading me in the right direction. But, I am not sure we are all on the same page. I may not be understanding exactly what you guys are telling me. First, my guess is that the kill switch/Man Overboard switch is the problem or at least one of them. I couldn't find the kill switch and don't know enough to guess on which wires made that loop. We have the starter/key of course but the MOB switch isn't on the controls.

Is the kill switch on the key and the MOB switch in the same loop? Do they both ground out the coils somehow?

I am glad the stator is working. That will be good news if I can figure out the spark issue.

I didn't think 4 coils would go bad. My feeling is that it is the safety kill switch grounding out the coils or a problem like gm280 is alluding to.

 

[gm280]

Thanks guys. I think y'all are heading me in the right direction. But, I am not sure we are all on the same page. I may not be understanding exactly what you guys are telling me. First, my guess is that the kill switch/Man Overboard switch is the problem or at least one of them. I couldn't find the kill switch and don't know enough to guess on which wires made that loop. We have the starter/key of course but the MOB switch isn't on the controls.

Is the kill switch on the key and the MOB switch in the same loop? Do they both ground out the coils somehow?

I am glad the stator is working. That will be good news if I can figure out the spark issue.

I didn't think 4 coils would go bad. My feeling is that it is the safety kill switch grounding out the coils or a problem like gm280 is alluding to.

If you don't have a kill switch or as you reference it man over board switch, then the only thing that stops the engine is the shorting of the spark system with the wires coming from the power pack module, as sudor alluded too. If those wires are shorted there will be no spark. So check the ignition switch and see how the switch looks with those wires attached. And once you do get everything working properly, install a kill (MOB) switch for safety reasons. JMHO!

 

[Bullie]

There was a MOB switch somewhere. The lanyard is laying in the boat so it must have had one. My buddy has stripped out everything. Its just the deck with a control box and a key to start it now. I know that doesn't give you guys much to work with. Is the kill switch usually in the same wire as the key?

 

[sutor623]

Do you have a control box or are your controls mounted in dash? A simple way to test is to disconnect the yellow/black wire from your power pack and see if she will start. BE AWARE!!!! If you do this and it starts, the only way to cut the motor off is to re-connect that black/yellow wire.

Kill switch on control box is where the lanyard is here: (Sometimes they are just under the key)


Or you can have an in-dash kill switch:

 

[sutor623]

See where the lanyard hangs off the box? There is a small black button that gets pushed in when the lanyard is in place. Pull that piece out and NO SPARK.

If that lanyard is hanging around, I think you will be pleased, as this seems to be reason that the boat won't start.

 

[Bullie]

The control box is there but the kill switch isn't located on it. The only other thing remaining is the steering wheel laying on a bare deck. So, likely it was on the dash somewhere.

I am thinking (hoping) that the problem is the kill switch too. Yellow/Black wire on the power pack. I will check that. Thanks.

 

[sutor623]

Normally, if there is a control box with a key switch the safety cut would be there. Not sure I have ever seen them in the dash unless the key switch is there also.

If you remove the yellow/black wire and the key switch is off, you should have continuity to ground. If the key is on, it should be an open circuit to ground. Let us know what you find.

 

[emdsapmgr]

Do a test. Remove the control box main harness wire at the red plug under the cowling. Jump the starter with a set of automotive jumper cables and a known strong battery. When the engine spins, check for spark. If you have spark, the problem is somewhere in the control box and the long harness to the engine. If you have no spark, the problem is on the engine.