Motor just died

[Eastbayboy]

I have a 2008 F40BTLR 40HP, 4 stroke outboard. This motor has always run great. Well, I just finished the seasonal maintenace (oil/filter, LU oil, impeller, fuel filter, plugs, greased everthing up, etc,etc). I took it down to the river for a test run. The motor started up wtih no problem, idling good, peeing out the back. Got away from the dock and slowly opened up to about 3/4 throttle and for about 5 minutes it ran great. Then it just stopped dead. No hesitation, no chugging, nothing. I countined trying to start the motor but there was no spark at all. I checked the 20 amp circuit breaker on the motor and a couple of others and all were good.

Not sure where to go from here and was hoping for some insight into what the problem may be.

Many thanks in advance!!!

[boscoe99]

Check the kill switch lanyard.

And if that is the problem then you should have heard the warning horn when the motor was being cranked but would not start. Then check the horn.

[Eastbayboy]

Good input, I did not think to look at the kill switch. However the kill switch is in place and there was no horn when I tried to start the motor.

[ausnoelm]

You say there is no spark, did you test this, or just guess there is no spark? you need to know if there is spark or not so you know which way to proceed.

[Eastbayboy]

Poor terminology on my part about no spark. No, I have not checked to see if a spark is present. I meant when the engine turned over there was no indication if the engine trying to start.

I will check the spark tonight.

[Mn carguy]

The fact that it killed so quickly makes me think kill switch as well. Many years ago, I had the same thing happen in a crownline. To make matters worse, there was a barge coming up the river. I was in his path and he was probably 3/4 mile away. For some reason, I thought of the kill switch and though the lanyard was attached, I pulled the knob out a little bit and it fired right up.

It was pretty scary as I had my one year old son on board and I don't know if the barge could have stopped in time. Anyway, something to try.

[Eastbayboy]

Pulled the plugs and checked the spark and the was absolutely nothing on all three plugs.

I will check the wiring on the kill switch. Does anyone know if it is a short or open when the lanyaed is in place??

Eastbayboy

[ausnoelm]

Pulled the plugs and checked the spark and the was absolutely nothing on all three plugs.

I will check the wiring on the kill switch. Does anyone know if it is a short or open when the lanyaed is in place??

Eastbayboy

The switch is open, it earths the ignition to stop the motor.

[Eastbayboy]

Ohmed the kill switch and it works as deigned.

I bought a service manual on ebay which should be in this Saturday. I will start working my way throught the ignition system till I find what died.

[Eastbayboy]

I guess it could still be the kill switch wiring. Until I get the sevice manual I don't know how to track the wiring through the system.

Eastbayboy

[Eastbayboy]

Received my service manual today and started going through the ignition system.
1)verified kill switch wiring and circuit is good
2. Verified pulser circuit is good using DVA
3. Verified charging circuit is good using DVA
4. Verified wiring from CDI to coils is good.
5. Verified coil resistance is good.
6. Verified no spark at any of the plugs with a spark tester.

It sure is pointing to the $450-500 CDI.

Any additional insight or incantations would be greatly appreciated!!!

Eastbayboy

[boscoe99]

67C-85540-01-00 YAMAHA C.D.I. UNIT ASSY

[boscoe99]

The switch is open, it earths the ignition to stop the motor.

Out on the water? How is this possible?

[Eastbayboy]

Boscoe99, Thanks best price I have seen yet.

[99yam40]

Received my service manual today and started going through the ignition system.
1)verified kill switch wiring and circuit is good
2. Verified pulser circuit is good using DVA
3. Verified charging circuit is good using DVA
4. Verified wiring from CDI to coils is good.
5. Verified coil resistance is good.
6. Verified no spark at any of the plugs with a spark tester.

It sure is pointing to the $450-500 CDI.

Any additional insight or incantations would be greatly appreciated!!!

Eastbayboy

Did you disconnect the kill wire from the CDI and then try it?