Honda 135 HP engine shutdown-intermittent

marcagrin

With only 270 hours use, my starboard Honda 135 hp engine suddenly quit while accelerating during a lengthy trip. Despite a well charged battery,adequate good non-ethanol fuel, adequate oil, I could not restart the engine for over 1 hour. No audible alarms or warning lights appeared.This same scenario repeated 4 times during the trip. After several hours, I could restart the engine and it performed flawlessly- until the following day.
A thorough evaluation by the local Honda dealer revealed absolutely nothing. The computer check was perfect. The thermostat, wires, gas lines,gas tank, filters , pump, anti siphon valve , water separation filter were all fine. I have ,thus far, been unable to recreate the engine failure locally(despite urgent attempts) so that the marina can run a computer check isolating on the moment of failure.
Any suggestions?

Marc G
2008 Tomcat

BrentB · Posted: Thu Jan 14, 2016 9:45 am Post subject:

I don't know but good at asking Qs.

Since fuel problems have been checked them I would suspect electrical problems. Have you inspected the battery cables to the OB have good crimps, tight connections and using nuts not wing nuts on the battery? Maybe it is the cut off switch is going bad or poor connections. The switch can be cleaned and lubed, and inspect the connections. When the OB is running do you have water discharging as tell tale stream?

Brewkid · Posted: Thu Jan 14, 2016 9:57 am Post subject:

Did you try and prime the fuel bulb right after it died? If so, did it have pressure on it? If not, I would go back to checking fuel lines. Mine did the same, ended up being the connector at the motor.

marcagrin · Posted: Thu Jan 14, 2016 12:15 pm Post subject:

The priming bulb worked fine (I replaced it just to be certain.)Electrical connections look good. Water stream indicator from motor is good.

BrentB · Posted: Thu Jan 14, 2016 1:34 pm Post subject:

check the OB wiring harness connection from dash to OB if present
pull apart connection, clean and add dielectric grease

BrentB · Posted: Thu Jan 14, 2016 1:35 pm Post subject:

When the event occurs, do it completely die like being turned off or does is slowly die?

Brewkid · Posted: Thu Jan 14, 2016 3:10 pm Post subject:

Marc,

I don't suspect your priming bulb being bad, however when the engine starves itself for fuel, possibly do to a very small air leak or clogged vent line, the bulb would not be pressurized keying us in to a air leak. The "during acceleration" still leads me to think fuel starvation. How long have you ran the engine at higher RPM's since the last fault?

John

BrentB · Posted: Thu Jan 14, 2016 3:27 pm Post subject:

I think John makes a good point.

In addition to his comments, do you have inline fuel flow meter (factory or after market, most are paddle wheel type) to this OB? It might be installed in the fuel line after the external fuel filter (ex Racor) and before the filter under the cowling. You could bypass it and take a test run

chimoii · Posted: Thu Jan 14, 2016 3:40 pm Post subject:

marcagrin · Posted: Thu Jan 14, 2016 4:31 pm Post subject:

The engine quits suddenly and rapidly. The bulb seemed well pressurized the one time I remembered to check it. I have recently run the engine at 4500 rpms for 15-20 minutes twice without issues! Will attempt to recreate the problem this weekend.

rogerbum · Posted: Thu Jan 14, 2016 5:33 pm Post subject:

That sounds like an electrical gremlin that will be very hard to chase down. I'd probably disconnect and clean and reconnect, every possible electrical/electronic component that is directly attached to or internal to the engine (and relatively easy to get at). Whenever, I've had weird electrical things going on, cleaning and reconnecting all the electrical connections often resolves them with no return of the problem.

Miafun1 · Posted: Fri Jan 15, 2016 6:30 am Post subject:

The neutral kill switch sounds suspect. I've had them go intermittent on other brands.

Wefings · Posted: Fri Jan 15, 2016 9:57 am Post subject:

We just sold a brand new Tohatsu/Honda 90 and on the second day of use the main engine control relay went bad . It would turn over but not start . One of our trained technicians went through the troubleshooting procedures as outlined in the shop manual and that's where it led him.
Marc

marcagrin · Posted: Fri Jan 15, 2016 9:49 pm Post subject:

I am still attempting to recreate the problem-without success. Hopefully I have cleared some type of fuel block by changing the Racor filter, priming pump, examining fuel lines etc.
For me, the crucial but confusing issue is that after engine shut down, the engine would turn over but not start for one hour or more. Then, it would run fine for hours. None of the many excellent and appreciated suggestions from c-brats explains this consistent delay in engine response.
Marc G

Dreamer · Posted: Fri Jan 15, 2016 10:28 pm Post subject:

There is an overheat protection feature built in to the processor. These engines have 4 temp sensors. It only takes one bad one to kill the motor. BTDT. There is a test procedure for the sensors. I missed a trip to Lake Powell waiting for a new one.