1984 Mercruiser 140 Wierd issue

[festeraeb]

I bought an 1984 sea ray 18'6" with a mercruiser 140 in it. Took it for a short water test seemed to run good. I installed a second battery and battery switch. Boat has new impellor. Took it out for a few hours and it ran good. Pulled into a dock and went in for dinner came back out and it would not start. It would fire then die as soon as you let prusseure off the key. It would stay running if you kept the key tuned toward the start position just shy of engaging the starter. Once in gear on this model the starter will not engage. This worked to limp back to dock on the other side of the lake. I say limp because the engine only had about half power and was missing.

I of course at the time assumed bad wiring or ignition switch but was confused why it ran so good earlier and just started acting up. Upone return to the dock and inspection the boat had about 5 gallons of water in the bildge. My thought is a leaking seal at the outdrive which seeped water into the bildge when sitting at the dock while we were at dinner. grounding out wires and causing (ground) and other electrical issues.

Anyone have anything similar or can suggest otehr theories to try and test or trace.

Going to hook the muffs up tomorrow and try to isolate the leak and see if it runs diferent "dried out" and on land.

 

[Bondo]

Re: 1984 Mercruiser 140 Wierd issue

I bought an 1984 sea ray 18'6" with a mercruiser 140 in it. Took it for a short water test seemed to run good. I installed a second battery and battery switch. Boat has new impellor. Took it out for a few hours and it ran good. Pulled into a dock and went in for dinner came back out and it would not start. It would fire then die as soon as you let prusseure off the key. It would stay running if you kept the key tuned toward the start position just shy of engaging the starter. Once in gear on this model the starter will not engage. This worked to limp back to dock on the other side of the lake. I say limp because the engine only had about half power and was missing.

I of course at the time assumed bad wiring or ignition switch but was confused why it ran so good earlier and just started acting up. Upone return to the dock and inspection the boat had about 5 gallons of water in the bildge. My thought is a leaking seal at the outdrive which seeped water into the bildge when sitting at the dock while we were at dinner. grounding out wires and causing (ground) and other electrical issues.

Anyone have anything similar or can suggest otehr theories to try and test or trace.

Going to hook the muffs up tomorrow and try to isolate the leak and see if it runs diferent "dried out" and on land.

Ayuh,.... Find yer Leak, 1st...

Then you can figure out Why the ignition circuit is Dead...

 

[Don S]

Re: 1984 Mercruiser 140 Wierd issue

For your leak, put the boat in the water, open the engine hatch and get down there an look. Only way you are ever going to find it.

I of course at the time assumed bad wiring or ignition switch but was confused why it ran so good earlier and just started acting up.

That's the way things fail. good one minute, bad the next.

If you ever have a problem like that again, keeping a long jumper wire on the boat with alligator clips on it. You just hook the jumper to the positive battery cable and the + terminal of the coil, and you completely bypass the switch and wiring.

 

[festeraeb]

Re: 1984 Mercruiser 140 Wierd issue

Great Ideas thanks. I was going to try the muffs just to see if the leak is in the cooling system then if it stays dry I will do as you suggest and put it in the water.

Great idea on the ignition coil....had something that would have worked and wasnt thinking....Was to flustered lol