225 pro xs won't fire

[jab0106]

2011 Mercury ProXS 225 HP 1226P73ED - 1B867912

Hit something in the water last night just after planning off and beginning the trim up, guessing 30mph and 4000-4500 rpm. I let off the foot on the surprise of the hit and motor quit about 10 seconds later. Once it was off, never fired again. Turns over as normal, just not firing. Checked kill switch, seems to work fine as it turns over with less loading. Checked throttle position and seemed to be working correctly and would only turn over in neutral. Disconnected battery power for a couple minutes to see if a reset occured, nothing. Hand spun prop without any noticeable issue or wobble or scarring of prop.

Any ideas where to start? Currently planning to pull the flywheel if I can to see if the key broke, and a spark test. TIA

[Savage]

There is no "key" that can break under the flywheel. Does the motor have spark?

[jab0106]

Hmph. That is disheartening. My current local mech was the one that suggested I pull it and see. I'll start with the spark then. Thanks for the belay.

[jab0106]

Update:. Spark test showed no spark on any plug. Checked all fuses and found one 20a fuse in the harness containing 4 20a fuses blown. Replaced the fuse and motor fired as normal.

Now I don't know what made the fuse blow. Will run the boat this weekend to see if all is well. Anything else I NEED to check before then?

[Savage]

Fuses blow because of a SHORT to GROUND. Inspect the wiring harness for chaffing.

[jab0106]

Update:. No harness chaffing found. Hit the water. Boat fired up, and blew the fuse within seconds of normal idle. Flipped the kill switch repeatedly, replaced fuse, and refired with same result. Disconnected one coil and replaced fuse, refired and fuse blew while engine seemed to be in runaway. Fuse that's blowing is consistently the 20A bottom, side, fuse in the ignition coil harness. Next step?

Thinking I need a coil, and replace one at a time until fuse holds, which I could do with a single coil kit.

[jab0106]

Got some time this weekend to work on this thing a bit more.

Is there a best method to test the coils without firing the motor and blowing the fuse each time?

[JOE54]

unplug all the coils replace fuse, plug coils in one at a time when fuse blows replace that coil,= cost one coil one fuse

[jab0106]

I appreciate that. Will get on it now.

[Nova Kaw 650]

Deleted due to not reading the entire post, lol

[jab0106]

Ok just did the test with no fuse blows, but there was also no crank until 3 coils were plugged in, but did find coil 3 to be warm to touch after while all others cool, and now have 9 beep alarm at key turn

[jab0106]

Bump. Any ideas on key turn warning beeps (8-10) before cranking?

[SilverFox579]

Time to have a well qualified Mercury tech read codes - WARNING HORN "BEEPED

[jab0106]

I will get codes read, but that link doesn't reference the beep config I am experiencing. It's not solid, and it's easily double the 4 beep warning.

[jab0106]

Update. Got this fault shown last night late.

Screenshot_20190501-223931.png

I suppose I should check the 20/5/2 fuses again first.

[EuropeanAM]

Check to make sure the TPS is connected to the link arm, and to it's wiring harness connector.

[jab0106]

Back on this motor again. Found cam assembly incorrect when pressing hotfoot to WOT, got realigned and beeping has stopped, gear shifting was also very stiff (probably from jamming up a bit from wrong cam position while shifting, shifting to full reverse cleared and now as normal, fault has cleared, back to popping fuse on cranking.

Assuming that fault was blocking full power which prevented blowing fuses while in fault, engine idled fine while faulted.

I'm planning to check out coil packs and either replace a faulty one or replace coil harness.


Any other steps that would make more sense?

[Savage]

Seek a Trained Master Mercury Technician.......Nothing was "blocking full power".

[jab0106]

Ok so swapped coil pack with the one that got hot previously, and presto, no more fuse blows.

Will provide another update once water tested.

[JOE54]