Optimax 150 warning beep and stall

[prodjsaig]

I was laying some crab traps and the main engine stalled out while at idle and started an intermittent beep and run rough. I checked the compressor and all seems good. I can start the motor but have to increase the idle to keep it from stalling. I narrowed it down to either a direct injector short, fuel pump blockage or coil short.

I had just installed the kicker and didn't have it ready to go and ended up bashing into some rocks. Luckily I got it restarted and recovered and little cracks to the gel coat on the hull edge. Looks like ill be using some gelcoat repair with hardener and bottom paint.

I am going to open the vst and look for any crud or possibly a seal that has cracked on the pump outlet. I also found the smartcraft 10 pin harness tucked under the block and will hook up vesselview to verify the code.

I fuel pump fuse is blowing which is shared ecm driver, oil pump and fuel pump circuit.

Im thinking its fuel related possibly from ethanol or who knows? I pulled all my fuel injectors and they are clean and I back flowed them with carb cleaner. Next is to test the direct injectors for shorts.

20 year old fuel pump. So maybe that's the problem.

 

[prodjsaig]

here are my babies just trying to get everything going again before the fishing opening in aug.

 

[beemer]

Could be the reeds. Is they are stainless replace with Boyesen carbon fibre

 

[prodjsaig]

Could be the reeds. Is they are stainless replace with Boyesen carbon fibre

That could very well be the problem. Ill have to inspect that and order a set. I narrowed it down to fuel pump strainer, throttle position sensor or now that you mentioned it maybe a reed valve.

 

[Sailfish25]

It is probably worthwhile pulling out the direct injectors and doing the same cleaning / backflow procedure as you did to the fuel injectors. The fuel injectors are usually not an issue, but the direct injectors tend to be fussy. Keeping them clean (with cheap Amazon ultrasonic cleaner and cycling through with 9volt battery) has been the key to keeping my Optis steady at idle.

 

[prodjsaig]

I'll one or two seals for the direct injectors can't afford too much more of this lol. All new seals for fuel injectors at around $100. Maybe I'll just do the di seals while I'm at it. Funny how one little problem has the entire motor basically apart. Good times.

 

[Ringo]

Sounds like a water in fuel problem. Have you tried to hook up a portable tank with fresh gas and give it a try? One test is to drain the vst into a glass jar and see if there’s water or debris at the bottom. Ethanol in gas can cause a lot of problems.

 

[prodjsaig]

Ya it just snuck up on me boat ran fine for a solid 2 hours and then stalled out when just idling. Hard to start need to increase throttle right after key turn and need to keep rpm above 3000 to keep from stalling out. now tripping the fuel pump. I did see rust bleeding out of the outboard fuel water separator where the alarm sensor is. Probably water in the vst.

A look at the history of the outboard and #3 and #5 air injectors were replaced 3 years ago due to no good. Im thinking its probably a good thing this happened so I can really stay on top of it install this smartcraft monitor. The boat had no monitors lol. I tripped pretty hard when this happened.

 

[prodjsaig]

Problem found #6 direct injector resistance low .8 ohms. got a couple used ones coming. will backflow all direct injectors with the 9v battery.

 

[prodjsaig]

Also the bottom coil driver was .68 ohms and are meant to be .97 ohms. Replaced that as well.

 

[prodjsaig]

Watch it lives

 

[ship happens]

Pretty sure only thing that can make a beep at the helm is overheat, and low oil either in the tank or in the small tank on the powerhead.

 

[gunnerlove]

Pretty sure only thing that can make a beep at the helm is overheat, and low oil either in the tank or in the small tank on the powerhead.

Or trim fault

 

[ship happens]

Or trim fault

Your right. However I think that's the second and 3rd gen only. Also only when smartcraft guages are used in the system. But at that point the guage will clearly say the fault code

 

[prodjsaig]

Your right. However I think that's the second and 3rd gen only. Also only when smartcraft guages are used in the system. But at that point the guage will clearly say the fault code

Ya it was the oil fault I replaced the tank but the double oiling is using a lot of oil so with the lid off was still drawing down

 

[beemer]

My experience is when you get a oil fault on the smart gauge , I lift the cowling and manually fill up the backup oil reservoir. Seems to always work.

 

[ship happens]

That design works on manifold pressure. Basically it's robbs the intake side of the cylinder block of manifold pressure through a 5/16 line, to the oil tank. The oil tank gets pressurized, and so fluid flows through the output of the tank into the smaller gravity feed tank that is located on the powerhead. Same as the carburetor version of mercs oil injection. Dumb really. Cap loose. No oil. Engine tired. Not enough. Reeds leaking, not enough. Oil pump running too much oil.. not enough. Gotta love those optis

 

[profisher]

Was talking to another guide who runs an Opti about times we have both had when the tank on the engine wouldn't fill and the engine alarms. I carry spare oil in case I have to ever manually fill to silence alarm and get home on the main without running it out of oil. He had a good idea he bought a clear mustard squeeze bottle and keeps it full of oil...easy to fill engine tank in waves without spilling all over the place. During a time when mine wouldn't pump and until I isolated why..I rigged up and plugged in a remote toggle switch which I had tucked in the battery compartment in the boat. I could fill the tank without removing the engine cowl. I ran to Otter, pulled the engine cover and timed how long it took to fill the tank, From then on I just used that time to hold the switch to fill it. At the end of the day I would lift the hood at the dock to visually fill it for the next day. Eventually replaced the engine wire harness which was over 20 years old and had hidden corrosion somewhere.

 

[ship happens]

It's a completely pressurized and gravity feed to the actual pump. Period the end. On the oil supply side. Zero electronics involved. Period the end

There is a sensor in the powerhead reservoir, same with the yommies. That also indicates oil low or no oil alarm. Only thing yamaha did different was put an electronic driven pump in the boat mounted oil tank. Which was fairly rock solid did fail after time just like everything else. ETEC did it the best. History in the making