Engine Starting Issue

[alldodge]

Your exhaust manifolds have catalytic converters inside them (Cats) so you have a high tech motor. Being your original motor was a 1994 it was not a Cat motor and would cost much less, also was not complex to figure out what was happening with it

The drive lube is low

 

[hwclark]

Thanks
You have a EC motor(Cats), cable control, closed cool (heat exchanger)

Your drive lube monitor is below the low mark

Side note: being a 94 model boat I would have done anything to stay away from Cats

Thanks so much. At this juncture, I think I will proceed as follows:
1. Fill “drive unit monitor”
2. Check fluids including coolant
3. Run engine at the dock until warm to ascertain if “engine cut off occurs” or it runs hot?
4. If all is good at dock, run boat nearby at normal rpm; say 3200 to ascertain if issue occurs?
5. I will be taking boat for “annual service/winterization” in mid December. I will have diagnostics done at that time.

One other thought. When installing a “salt water wash down pump” on the boat two weeks ago, the voltage at the pump was less than 12. The pump would not operate. We are thinking some sort of wiring issue? Any impact or sign as to engine cut off issue?

Your thoughts on procedure?

 

[hwclark]

10/16/22 Note the motor’s computer (PCM) was installed new a year ago.

 

[tpenfield]

Greetings . . .

Welcome to the abyss of marine engines

The engine looks like the 350 MAG with the CATS (Catalytic converters). The good news is that it is a SeaCore version, so it has a full closed cooling system. These engines were used for a while to fill a 300 HP 'gap' until Mercruiser came out with their own in-house built 6.2L. Anyway . . .

It will be quite difficult to diagnose the engine issue(s) without the computer diagnostic software hooked up to the engine.

What do you have up at the helm for engine gauges or displays? (maybe VesselView? Post a picture of the helm/instrument panel(s) as that can tell.

Are you getting any error messages or warning 'beeps'?

What do you have for batteries on the boat? Can you put a volt meter directly on the batteries and get a voltage reading? In my experience, a low voltage situation can raise issues with the engine computer.

 

[alldodge]

One other thought. When installing a “salt water wash down pump” on the boat two weeks ago, the voltage at the pump was less than 12. The pump would not operate. We are thinking some sort of wiring issue? Any impact or sign as to engine cut off issue?

Your follow up procedure is good

As Ted mentioned, check voltages at the Battery post. Check before starting and after. Before should be 12.7 to 12.6V, once running it should be close to 14.5V

With it running, find the 50 amp breaker on the motor and check voltage there. Could be power is dropping and that's causing the issue

 

[tpenfield]

There are typically two (2) voltage references that the PCM is looking for . . . 12 volts and 5 volts.

You will get warnings if your 12 volt source is too low and at some point (10.7 volts IIRC) the engine may shut down.

 

[hwclark]

10/15/22 Will check on "error messages" at the helm? Will be at boat on say 10 days.

Have 2 new batteries on the boat. Will check voltage when I return in say 10 days.

Good thoughts! Thanks a bunch.

See helm picture. Hour meter not working.

 

[alldodge]

Not saying the folks did a bad thing installing a CAT motor, but they didn't do you any favors. You got a good motor but it went from being easy to work on, to one that can only be worked on by a trained professional

They could have bought a Reman and used everything off you old motor, or could got a Reman and bought all new parts to make a new motor.