Help Please.. Mercruiser 305 Problems..

[greg82255]

Hello again,

So I just put my boat in the water for the first time this year. Its a 1982 Mercruiser 898 (305) with an Edelbrock intake and Holley 4 barrel that I added in the off season. I was cruising around at 40 or so for about 20 minutes and all of a sudden I hit a wave and the engine shut off while it was in gear and going 40.... Boat came to a complete stop and water splashed everywhere from behind the boat. I tried to turn the key to turn it back on and nothing would happen. Engine not turning, not even a clicking noise that would indicate a bad contact. All the connections were good, and I am sure the battery was still working because I wired some lights not through the wiring harness, and was able to turn those lights on and off. I assumed that I tripped the 50 amp master circuit breaker for the engine. I pushed the red breaker button back in and the engine fired right up.....

I am wondering what might have caused the breaker to be tripped... What should I check for? I want to put the boat back in the water tomorrow.. Any thoughts/comments would be helpful. Thanks.

 

[Don S]

Re: Help Please.. Mercruiser 305 Problems..

Sometimes they trip for no reason. Seen it many times. Reset and no problems again.

 

[JustJason]

Re: Help Please.. Mercruiser 305 Problems..

I've seen it to. The worst is when you do a tune up/service on an engine, customer tows it 50 miles north... calls you screaming that there is no power to anything. It trips during towing sometime to. Me thinks it's spring loaded inside of that breaker... and sometimes the spring mechanism trips when it isn't supposed to.

 

[greg82255]

Re: Help Please.. Mercruiser 305 Problems..

Alright, thanks guys. I'll take it back out today and hope for no problems. If it trips again, I'll repost on this thread.

 

[greg82255]

Re: Help Please.. Mercruiser 305 Problems..

Problem Not Solved......

I went out to the boat this morning and tried to start it. Turn the key, nothing. I went back to the breaker and saw that it was tripped again. I pushed it back in again and the boat started right up. I ran it for about 5 minutes, and then waited a minute or 2 and tried to start it again. Nothing. This time, the breaker was not tripped... I tried to start it for a few minutes and got nothing. After about 5 minutes of checking everything and finding no problems, I turned the key again and the boat started right up... Then I turned it off and tried to start it again and got nothing, again. Then I came inside and wrote this post. Anyone know what this might be??

 

[zbnutcase]

Re: Help Please.. Mercruiser 305 Problems..

Maybe a dying slave solenoid or neutral safety switch. When it wouldn't start when the breaker was not tripped, was there power to the gauges when you turned the key on?

 

[greg82255]

Re: Help Please.. Mercruiser 305 Problems..

Yes, there was power to the gauges. Which would more likely be the problem - slave solenoid or neutral safety switch?

 

[zbnutcase]

Re: Help Please.. Mercruiser 305 Problems..

Hard to say in your case, but I do replace more solenoids a year than neutral switches. I think there is troubleshooting info in the Adults Only section at top of page.

 

[greg82255]

Re: Help Please.. Mercruiser 305 Problems..

Thank you, much appreciated. I'll go troubleshoot and post what the problem was.

 

[greg82255]

Re: Help Please.. Mercruiser 305 Problems..

So I went to the adults only section and followed the steps to test for faults. I found that the solenoid is fine, as is the neutral safety switch. The ignition was gone.. I replaced it and the boat started right up.

I am not so convinced that the problem is gone... I still want to know what caused the ignition to die... and why the main fuse on the motor was blown twice. Any thoughts?