2001 johnson 50 shutting down at or near wot

[tkoons]

this motor started doing this a couple of months ago. called dealer he said to change powerpack,did that.ran ok for awhile then started doing it again but less frequent. talked to another mechanic he said it was carbs. i suspected not because of the instant shutdown.another mechanic said it was probably under flywheel.meanwhile i started losing trim power and found a faulty ground on regulator screw. i played with the ground wire and the trim started working but still comes and goes. ill have to crack the cases to get to the screw to permanantly fix. but my question is could this screw be the culprit with the engine problem?

 

[Texasmark]

Re: 2001 johnson 50 shutting down at or near wot

Couple of things.

1. Sure it's electronic? Try squeezing the bulb when it wants to shut down. Can you feel fuel in it or is it collapsed? Fuel in it?..........squeeze and see if engine recovers; if so fuel pump diaphragm is where I'd start.

If it is collapsed, fuel supply restricted.....tank vent closed, pickup screen clogged, fuel line clogged.

You have a carb per cylinder I'd presume. Doubt that both would exhibit the same problem at the same time. One might cutout but the other would keep chugging.

2. At WOT all the electronic circuits are working at max capacity. That means max current/power is being consumed which means currents are at their max as is heat. If you have a bad grould wire that can't supply adequate current to to operate the circuit then yes the screw could be the culprit.......but I really don't think that it's that cut and dried. I'd think that some current could/would be carried and the engine would miss or cut down in rpms, but not completely quit.

Mark

 

[tkoons]

Re: 2001 johnson 50 shutting down at or near wot

i tried the bulb thing. had someone dive boat and i squeezed ,bulb was tight and pumping didn't make it recover. Ialso failed to mention that a couple of times that the rpm was slow on take off and could tell it was going to die and it did.most of the time when it happens the motor will start right back up .but once it took a good half hour to refire.

 

[Silvertip]

Re: 2001 johnson 50 shutting down at or near wot

Instant shut down is more than likely electrical. Since you have a kill switch, make sure the lanyard is firmly in place and that the switch itself is not making intermittent contact. The ignition switch is another possibility. Both of these potential sources can be verified by starting the engine. Then disconnect the big red wire harness plug at the engine. If the problem is now gone, there is a problem in the harness or control box. You will need to reconnect the plug to kill the engine. If that doesn't solve the problem, as Mark says, check every ground connection on the engine, especially the one for the pack. Just for the record -- does the warning horn beep when you turn the key on?

 

[tkoons]

Re: 2001 johnson 50 shutting down at or near wot

yes the warning horn does beep

 

[Silvertip]

Re: 2001 johnson 50 shutting down at or near wot

OK -- just wanted to make sure you weren't getting overheat indications and not knowing it.

 

[clanton]

Re: 2001 johnson 50 shutting down at or near wot

If you are still having problems, check the pulse hose fron the engine block to the VRO pump. You should remove the starter. The starter end plate rubs a hole in the hose. grind notch in starter end plate to clear hose.

 

[DJ]

Re: 2001 johnson 50 shutting down at or near wot

i played with the ground wire and the trim started working but still comes and goes.

That's a major clue.

1. Remove and clean the negative battery terminal where it attaches to the engine block.

2. The other ground wire can easily be relocated by lengthening it. I certainly wouldn't disassemble anything because of that.

 

[chris abela]

Re: 2001 johnson 50 shutting down at or near wot

it is simple when youve been through it.

The cause is lack of oil coming from the oil tank.

The cause is that the oil breather hole is probably clogged and if you notice the oil tank should look deflated.

Just remove the cover on the cap, must be broken off and make sure the hole is open.

It happened on a 2000 Johnson 50

 

[tkoons]

Re: 2001 johnson 50 shutting down at or near wot

that brings up another question i have. the manual says something about the engine shutting down when it senses lack of gas to the carbs to keep the carbs from flooding with oil but i haven't seen anything in there about any sensor that actually shuts it down for lack of oil.

i've had a couple of guys at the ramp tell me they knew of a couple of engines they knew of that were shutting down when the tanks got too low or some other cause of losing oil occured. one of these was a 50.

so do these motors have an auto shut down for lack of oil or not? and if they do why aren't the warning alarms working first?

 

[Silvertip]

Re: 2001 johnson 50 shutting down at or near wot

No they don't. There are three warnings associated with the warning horn. Intermittent beeps can also signal a fuel restriction but I doubt that's the problem since you idicated the engine acts like the key is turned off w;hich would seem to indicate an ignition problem. A steady beep indicates an overheat condition regardless what the cause is. There are two oil alarms. Beep's a few seconds apart signal no oil. A beep every minute or so indicates low oil. An overheat condition causes the engine to go into S.L.O.W. mode which is a speed limiting feature. When activated, the engine will not rev over 2500 RPM and it acts like its missing (which it is). That is a "limp home" feature. Oil warnings do not shut down the engine. If the problem occurs when the big red engine harness plug is disconnected there is very likely a power pack problem. If it doesn't, then there is a harness, kill switch, ignition switch problem. Until you do that test you can theorize for days and not prove anything. I firmly believe you have a pack problem or its ground or other connections are not solid. I've seen where the main connector pin is pushed into the connector housing and not making good connection with the mating half of the plug.