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454 mag efi/mpi died while running

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Old 09-22-2019, 09:18 AM
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Default 454 mag efi/mpi died while running

I have a 1996 crownline 225 ccr with a bravo one outdrive. I just put a new prop on my boat and took it to the lake to test it. Boat got up on plane real nice and cruised around 40 mph. I was happy so thought I'd go for a long drive. I get up river about 5 miles and suddenly I could feel the hp was dying quickly so I put the boat in neutral and when the boat finished coasting I tried to start it again. The engine wouldn't budge. It tried but acted like something was seized. I had my buddy pull me back down river to drink some more beer in our usual spot 2 hrs later I decided to turn the switch. This time it's turning over. I start the boat engine sounds good so I decided to see if it would die again. Put it on plane and 2 minutes it does it again. Sure enough it does the exact same thing. Died and wouldn't start. Anyone ever hear of a gimbal bearing going out like this? Or what else could cause something like this? Im not thinking it's fuel related since the engine wont turn over.
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Old 09-22-2019, 09:45 AM
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Don't see a bearing doing this

Stopping real quick and with thru hull exhaust my have ingested water. Check your oil level

Is it overheating?
How was the oil pressure?
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Old 09-22-2019, 10:40 AM
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Just checked spark plugs and no water in any cylinder, oil pressure was good good and didn't overheat. The weird thing is it turns over now but soon as it gets up and running it will lock up again. I don't remember having any gimbal bearing noise. Only thing I can think to do now is remove the outdrive and run it on the hose for a hr or so.

When it started back up in the water it idled fine and sounded good. It planned off fine but soon as I made a turn and gave it throttle I could feel the rpm dying down again. I back off the throttle and tried to plane again and it wouldn't get up and over. It slowly just died again and engine wouldn't turn over again.

My thinking is the gimbal bearing has water getting in and is getting hot. Enough to shut down the engine and not start again. Once it cools down it allows it to start up for a brief time until it's hot again. If this isn't the case maybe it's electrical. Once the engine heats up a connection is losing contact killing the engine from powering the system but I just don't see this one happening.
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Old 09-22-2019, 10:42 AM
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Also I was running in the water for 20 minutes at 3000 rpm so no sudden stops when this happened.
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Old 09-22-2019, 10:51 AM
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A gimble bearing will not stall an engine. It could be a neural safety switch that will not let it crank. Sounds like you have a fuel or spark related problem. Time to do some testing of fuel pressure and spark.
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Old 09-22-2019, 10:53 AM
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Might be running out of gas, but the issue is your saying the motor sized, as in will not crank

Check lube in drive and pull it
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Old 09-22-2019, 10:56 AM
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I don't think it's a neutral safety switch because I can hear the engine try to turn over but something is bound up and wont let it spin far. I have personally had a gimbal bearing stop a motor at cruising speed so I know its possible but what I've never had happen is that bad bearing allow the engine tip spin over 2hrs later.
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Old 09-22-2019, 10:57 AM
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The lube monitor shows the level to be fine but I will check the outdrive. Is it possible the bravo one could be seizing?
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Old 09-22-2019, 01:00 PM
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Well I did find drive lube in the gimbal below but the gimbal bearing felt good. Now im at a total loss. I have no clue where to start. I cant hardly believe its fuel related because the boat should have at least spun over after it died. Instead it tried but wouldn't turn. So im thinking sensors are out because it tried to spin, fuel is out because it wouldn't turn over, gimbal bearing felt good, no water in cylinders or oil, maybe electrical connection somewhere? Although should have clicked or not tried to spin over if that was the case.



Where i believe the drive is leaking lube into the bellow.
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Old 09-22-2019, 04:49 PM
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Where the heck is the Sleeve ?
What Nimrod put the bellows in, there is your leak



If that is a grease-able bearing it might be savable, but if not it needs to be replaced
With maintenance like this I have no idea what's the matter with the motor. It could be nearly anything
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