I may be in over my head!!

[csellars]

I am trying to help out a couple of friends that just purchased a 2000 Challenger 2000 240EFI. They had a mechanic that was evaluating the engine and determined that the fuel pump needed replacing. The parts were ordered and should be coming in soon. The problem is that the mechanic went to bed last friday and did not wake up!!!. My engineering background makes me their first resource for evaluating their boat problem and since the mechanic was a close friend of theirs I would like to help relieve the burden of fixing the boat for them.

Here is what I know:

The engine ran well on the hose, but the Overtemp/low fuel horn was blaring. They solved the problem by disconnecting the horn planning on addressing it later. Not sure what the indication was requiring the removal of the EFI system and the fuel pump, but the mechanic was a top notch type of guy so I am sure he had a good reason.
I have the engine manual but it does not have any wiring diagram for the console. I am planning on troubleshooting this problem for them while they are waiting on the fuel pump to come in. Since the engine ran well on the hose I am assuming that the Head temperature sensor is working right, (this is critical to setting mixture I think) so I am still trying to understand fully the dual nature of this horn (maybe the console wiring diagram can shed some light on this).
I am willing to purchase the premium membership if I have some assurance that the proper wiring diagrams are available. I will also be looking for some answers as I reassemble the Fuel Injection system.

Thanks in advance, this forum seems like it will be an invaluable resource. I am looking forward to any assistance I can get.

 

[kustomkarl]

Welcome to the seadoo forumcsellars. I opened the 2000 M2 210/ 240 hp manual in the seadoo forum library and the complete manual is there. Section 2D is the wire diagram. I hope the manual helps you get the jet boat running. If you have any other questions give us a shout. There are a lot of members that have the same boat, that can help answer any questions you might have.

Karl

 

[csellars]

Now I know a little more.

Thanks for the feedback Karl.

We have a M2 manual and I have been studying it. It has a troubleshooting section that indicates that if you disconnect the Head Temp sensor that the temp horn should stop. Since it does not stop with the sensor disconnected the indication in the manual is that the ECU is bad. I measured the resistance of the sensor and it appears to be in range per the manual and changes over temperature so I am assuming that it is OK. I also verified that the Low Oil indicator is operating properly ( beeping stops also ). When they had the engine running on Hose it ran well and did not seem to have any problem except the horn sounding so I am questioning if the ECU is bad. The reason that their mechanic recommended replacing the fuel pump is that the gas in the system was very bad from sitting more than 2 years. Another clue that may add to this is that there was no water coming from the brass orafice indicating proper water flow through the heads. Could a lack of water flow in the head cause steam pockets that might cause the overtemp indicator to go off?

Since the fuel system is down right now and I can't start the engine I am not clear on whether or not the horn should be sounding.

It seems to me like the horn should sound until the engine starts. This is not indicated in the manual.

Thanks again for your help

Craig

 

[kustomkarl]

I don't believe the beeper should sound till it starts. It sounds to me that it has a malfunction somewhere or a problem in the system. I'll look around for some insight on the problem and get back to you.

Karl

 

[csellars]

Horn is Dual function

The horn is a dual function device. It beeps if the oil reservoir is low and it blares if the Over temp is indicated. Just to clarify,,, the oil reservoir beeping is not the problem, it is blaring.

There are 2 different control units. One on the back of the engine and a smaller one on the top. They both indicate to be an ECU on the wiring diagram. The big one on the back of the engine appearantly controls the CDMs and handles the EFI timing. The smaller one on top of the starboard head is the one that the sensor connects to. the manual was not clear as to which one of these might be faulty. I am assuming that it is the one on the top of the engine and not the big one in the back. Any ideas on how expensive these parts are? If they are not cost prohibitive I may just replace them because they may be the problem.