1989 Mercruiser 3.0 Cranking but no spark.

[mjw210]

I have 12V at the ignition coil terminals. The stock coil was reading .9 Ohms from the coil terminals. I replaced the ignition coil thinking it was the culprit and same situation. It ran last year but I haven't gotten it out this year yet. Battery is good by the way. I'm assuming the kill switch is good because it cranks. And the button is pushed in on the throttle lever for starting the boat. I'm not sure what else to check unless I got a bad coil right out of the box? With power on the ignition coil terminals I would expect to see spark while cranking if the coil is good. Thanks in advance. Also is this the neutral switch on top of the motor? I'm getting 35 mega ohms on that so is this the issue?
-Mike

 

[Bondo]

Ayuh,.... What distributor ya got,..?? If it's got points, that's yer problem,....

 

[dubs283]

I replaced the ignition coil thinking it was the culprit and same situation...... I'm assuming the kill switch is good because it cranks......unless I got a bad coil right out of the box? ...... Also is this the neutral switch on top of the motor?

Not likely......kill switch means (to me and others here) lanyard/operator presence switch at helm/remote not neutral safety switch located inside the remote......again, not likely.....shift interrupt switch is located at the shift plate assembly (actually pictured just below your right hand in the photo.

As stated, if your ignition system is conventional/points the culprit most likely is under the distributor cap (points/condenser). If electronic, could be a couple different things but as mentioned not likely the coil

 

[mjw210]

Not likely......kill switch means (to me and others here) lanyard/operator presence switch at helm/remote not neutral safety switch located inside the remote......again, not likely.....shift interrupt switch is located at the shift plate assembly (actually pictured just below your right hand in the photo.

As stated, if your ignition system is conventional/points the culprit most likely is under the distributor cap (points/condenser). If electronic, could be a couple different things but as mentioned not likely the coil

I haven't checked under the distributor cap. But I did replace the condenser and points thing like 2 years ago. Maybe I'll order a kit for those and do them again. If I remember they were cheap and easy to install.

 

[mjw210]

Ayuh,.... What distributor ya got,..?? If it's got points, that's yer problem,....

Yeah it's a points setup.

 

[dubs283]

I haven't checked under the distributor cap.

This is #1 thing to inspect on a points system with no spark....

There is a troubleshooting guide in the stickies, top of forum page. Great reading in there for the curious ones

 

[mjw210]

Well the condenser wire was smashed for sure.

 

[mjw210]

Here's a short video clip of me doing the remote start. Even with the condenser wire half smashed it ran the last time I used the boat. The points, cap and rotor all look new. I'm not sure where to go from here. I don't have a timing light but that shouldn't have moved from when it ran last.

 

[Scott Danforth]

File the points
Set dwell with a meter
Set timing
Adjust idle speed

It's almost never the coil

 

[dubs283]

Even with the condenser wire half smashed it ran the last time I used the boat. The points, cap and rotor all look new. I'm not sure where to go from here.

Your problem is obvious

Scott says, use all new parts. Heed this advice and as always, use oem

 

[poconojoe]

You stated you assume the kill switch is good because it cranks. Please clarify.
If you mean the safety lanyard, the engine will crank all day if that switch is tripped. It won't start, but it will crank.

 

[mjw210]

I replaced just the condenser and lightly filed the contact points. It fired right up and idled beautifully. So looks like I have some spare parts to keep handy for the future.

 

[poconojoe]

I replaced just the condenser and lightly filed the contact points. It fired right up and idled beautifully. So looks like I have some spare parts to keep handy for the future.

Great!