Optimax 150 won’t start unless trimmed down

[keith63g]

MemberJoin DateMar 2023LocationStonewall laPosts1

Optimax 150 won’t start unless trimmed down

Starting last year on occasion after I had run across tge lake and fished leaving my motor up from the ride or raising it for fishing shallow water I’d get ready to motor to another place and hit the key…beep as normal, dash light up but nothing. Like the kill switch was thrown. After manipulating the motor trim a few times I realized that trimming it down fixed the problem. Took it to a local shop and he checked connections and main power lines. Could not replicate tge problem as I haven’t been able to at home either. Some trips it never happened. Couple days ago it was dead at the loading ramp from being trailered to the lake…launched and trimmed up and down couple times and cranked fine rest the day.
last evening I ran across a thread about engine oil reservoir switches going bad. I looked at my reservoir and it’s about 85% full. My main is also. Hooked engine to water hose and ran a few minutes and removed the main oil cap and had pressure.
Is there a way to check this switch on the water next time this happens? Unfortunately the connections are tucked down low and I’m not certain if I unplug them it’s going to be easy to reconnect while on water. Guessing I’ll have to beach the boat and wade the shallows to accomplish this.
If I just jump tge two wires will this bypass the switch ?
Any other thoughts on why this would be happening?
Serial # 1B298600
model # 1150D73FY

Thanks Keith

[JOE54]

do NOT be jumping any wires on that engine , and reservoir switches are not the problem . please use the v6 forum one more down list

[EuropeanAM]

Moving your thread to the 2.5L Forum.

Suggest that you disconnect/clean/reconnect the cannon-plug harness at the engine, and check the starter solenoid wiring to make sure it is properly secured to the starter.

[keith63g]

Well I’d read a thread on here somewhere where the magnet on the reservoir switches were pretty commonly going out. Wish I could relocate that thread. Anyway that’s what gave the idea. They were having to change the whole reservoir because the switch wasn’t accessible. Thanks

[keith63g]

I’ll check cannon plug harness at my next opportunity. Have checked lug bolts for tightness already

[styler]

Well I’d read a thread on here somewhere where the magnet on the reservoir switches were pretty commonly going out. Wish I could relocate that thread. Anyway that’s what gave the idea. They were having to change the whole reservoir because the switch wasn’t accessible. Thanks

Pay attention to Joe and European's advice they know their stuff on these.
As far as the on engine oil tank goes. What I think your referring to is when the float goes bad in that tank. As far as I know this wont cause the engine not to start. It will however give you an alarm because the ECU thinks that tank is low when in fact it is not.
This is a whole different issue than you are describing.

[JOE54]

^^^^^^^^ +1

[JOE54]

does electric fuel pump run when problem occurs?

[keith63g]

��*♂️. I’ll try n find out How do I check that. Everything seems like normal but it just does nothing when key is turned like kill switch is thrown

[leonreno]

I believe you should be able to hear the fuel pump come on when you turn the key to on/run.

[SilverFox579]

I believe you should be able to hear the fuel pump come on when you turn the key to on/run.

Yes he should.

[JOE54]

^^^^^^+1

[styler]

If it won't even fire when trimmed up but will when down it almost has to be a loose connection or broken wire. Id be going through every wire than moves when the engine is raised or lowered.

[JOE54]

agree ^^^^^^^^^^ possible broken wire at cowling exit of harness , but i would sure think you would have other electrical problems also

[TomP.]

Just a dumb one but wiggle your throttle shifter may be a tad out of adjustment and motor thinking it is in gear.

[EuropeanAM]

Also- please clarify/verify the difference between "won't do anything" and "won't fire".

Does the starter activate and spin the flywheel when trimmed up (Yes) or (No)?

[keith63g]

UPDATE: Went fishing a couple times and no problem. Then wham I go to start up n move to a new location and it’s dead. ( turn key and horn sounds but nothing from starter). Usually this is when I’d trim tge motor down but I got up and grabbed the bundle of lines running into the callum and give a tug. Then hit the key again and it starts perfectly. So this leads me to believe there’s a short in the wiring at the callum. Im looking and feeling the wires at home. There’s no indication of a bad spot. And of course the motor is firing fine at home

[keith63g]

Also after looking - feeling the wires the two #6 feel smooth. The larger one which plugs in and I suppose has multiple wires inside the sheathing feels a little less smooth where it enters the callum. Im thinking this is probably the problem. Should I peel back the insulation and inspect the inner wires insulation. Seems there would be some discoloration if it’s shorting. Replacing this whole cable looks like I’ll be removing the oil lines and cables just to make room to get the large connection end through the opening

[EuropeanAM]

If you peel back the protective insulation, you're going to end up replacing the harness (anyway). I'd be inclined to replicate the problem again, have someone hold key in start position while you:

-Move shifter
-Wiggle main harness where it enters the Cowling

[keith63g]

Went to lake yesterday and it quit for good. Tonight I peeled back insulation on wiring harness to find that tge hard round part it passes through the callan had been digging into a few wires and the yellow with red stripped was cut into barely connected by the insulation on one side. Stripped it and wire nutted back together and she fired right up. Ive got extra and I’m thinking of cutting the crimped wires….soldering them back together and heat shrinking them They will all be up inside the callan. Does anyone know a reason why I should not do this. I figure if it doesn’t last I’ve lost nothing and it’s fishing time now.