2001 mecury 50hp

[Dr Drift]

If u want to get to the bottom off it without stuffing around u gonna need quicksilver program and see why its going into limp mode. Might be cooling related might not. might be few issues? Or get manual and go through chart diagnoises(just takes longer). this is the whole point off modern day ecu......

[Dr Drift]

So u start motor...fine
runs fine than it slows your revs down?
What beeping noise does it make?
is it a continuous beep?

[polyskidmark]

So u start motor...fine
runs fine than it slows your revs down?
What beeping noise does it make?
is it a continuous beep?

Yeah motor starts fine. Runs for a bit then when it gets warm it reduces the revs and the alarm is a constant beep

Sent from my C6603 using Tapatalk

[Dr Drift]

What model is it?
is it 4 or 2str?

[polyskidmark]

4 stroke 4 cylinder

Sent from my C6603 using Tapatalk

[Dr Drift]

4 stroke 4 cylinder

Sent from my C6603 using Tapatalk

First let me state that the only way to be certain is in person. Or if u get DDT system to check out through ecu....
there is ways to sort off figure it out without DDT(quicksilver program).... by certain beeps and engine behaviour.
also I am trying to help through typing on net and can only go so far if u know what I mean?

When it shuts down into limp mode. can u rev to 2000rpm? or not rev at all?
or pm your no.

[frozenpod]

What do the impeller plates/housing look like.

[rixter]

The impellor looks fine, clean anyway / but ...is that impellor blade at the top flattened off , looks flattened, with a burr on the edge ? / ground down in the picture ? .
If not , then all ok , otherwise I would say the bearings for the impellor have gone and allowed it to grind away.
Hard to tell in that picture. Do any of the tops of the impellor blades look more polished/worn down that others ?

Personally I recon' it is going to be a the crankshaft sensor, if it isn't the cooling system. They are a sensor , and sensitive ! . Only takes a bit of a whack or bit of crap on them , and they will fault out , 80% of the time this is the problem when cars with ECU's (ecm's in a boats case ) crap out , it's usually just a dodgy sensor.

Gee , I've even had ecu's/ecm's play up due to a faulty main earth lead !, there is so much stuff connected to the electronic control module these days; that is could be almost anything . A diagnostics program is pretty much the best way to determine the problem without having to rip the motor to pieces. Take it to a Mercury specialist if you don't have the program and tools required, or if you don't know what your doing .

Cheers , Rick.

[frozenpod]

Rick, crank sensor is unlikely as typically engine wont run at all if they stuff up or if it is an intermittent fault with temperature they will suddenly cut out as they loose crank position.

[rixter]

or if it is an intermittent fault with temperature they will suddenly cut out as they loose crank position.

They don't all always cut out , sometimes they will just go back to safe mode idle speed to stop crank damage, and allow you to get home; Boat or Car.

Never know ? , could be anything with these new motors these days , so many sensors for all kinds of stuff. Only takes one thing to go out of whack a bit and the whole thing comes to a holt.

Personally if it was mine , I would just save myself the headache and get it plugged in and diagnosed. Could be an engine problem or just one of many sensors playing up. ?

Cheers , Rick.