1993 150 Johnson dies while underway

dgawoski

Cadet
Joined
Aug 17, 2008
Messages
6
This engine is clean with about 250 hrs on it, but it sat for a while. I bought it three years ago, and had the optical ignition pack replaced, cleaned or replaced some wiring, connectors, ignition switch, kill switch. First year it started and ran great. Third year it started first time, but died once while underway in rough water. Ran great other times.

This year it has been hard to start, engine cranks - seems like no spark with gas/oil coming out unburned from exhaust. Noticed the little beep status check of the SLOW system doesn't come on anymore when turning the start key. I replaced the battery, cleaned the plugs, checked the ignition switch with a meter. Checked the warning horn and it works.

When I do get started, the last three times out the engine will just die like I killed the engine after being underway for 3 to 10 minutes. Two out of three times it started right up again, sometimes dying again within a short time. Once it goes through this routine, the engine will run and start up fine the rest of the day.

The last time it took it out it started right up and idled fine. After getting on plane and cruising around 1/4 mile at 30 mph, the engine dies. Started up but died 5 minutes later. It took awhile but I eventually got it to start by disconnecting and reconnecting the battery, turning up the red lever (turn off fast idle start) and advancing throttle at carbs. I don't know what if any of this helped. It wouldn't idle, but ran when holding throttle back. Then I turned the red lever down and it started up and idled fine.
Engine ran fine the rest of the day, but noticed MPH and tach gauges were sometimes reading low or not at all.

Any ideas on what this could be, or anyone experience this? Thank you for your help.
 

jonesg

Admiral
Joined
Feb 22, 2008
Messages
7,198
Re: 1993 150 Johnson dies while underway

it sounds like multiple problems due to lack of upkeep,

did you ever rebuild the carbs?
or replumb the fuel lines?
got a water seperator?

Can you hear the choke solenoid click when pushing the ignition key in?
Put a timing light on the ignition wires when it won't start.
Does the overheat buzzer work when grounded to the block?

The v6's are very intolerant of being pushed when something isn't right.
You sure its not overheating on you?
 

dgawoski

Cadet
Joined
Aug 17, 2008
Messages
6
Re: 1993 150 Johnson dies while underway

It was the power pack.
I narrowed it down to the power pack, regulator/rectifier or stator coil. CDI electronics has good trouble shooting guides, but some of the valued they provide are for their parts only and my meter readings were slightly different. Still, using that info I had resistance or open circuits where it was supposed to be. I decided to replace the power pack as it was the least expensive part ($150), and about the same cost as a new peak load multi-meter and a meter DVA adapter needed to perform more part testing.

After I replaced the power pack, the engine runs like new. I was surprised this part had failed, since my marine mechanic replaced this part 3 years ago. The wiring on the failed part looked older than my engine, like it was previously used.
 
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