2000 Islandia 240EFI No power

[NewFoundBoater]

I have a 2000 Islandia with a 240 EFI Merc. Boat starts up and idles fine. The boat will run to 2500 RPM fine. Once the throttle is applied the engine whines out and RPM goes to max if I let it and boat just stays at about 10 MPH. I have had all the plugs changed and starter solenoid replaced. Compression was fine. Also had fuel pump checked and that was fine. Replaced the Fuel filter. Then replaced the ignition controller.
I am now being told that there are small filters with the fuel pump that have never been changed and need to be replaced.

Can anyone give me some advice?

 

[Dr Honda]

If the engine is reving up... then you are cavatating. Check the impeller, and the wear ring.

 

[NewFoundBoater]

Thanks for the quick reply, What am I looking for with the wear ring? Another piece of information. Once reving with throttle it sometimes acts like the engine wants to engage. You can hear small pops with a slight burst of power.

 

[onebadcav00]

could also be the seal on the drive shaft. that happend to me before

 

[Dr Honda]

could also be the seal on the drive shaft. that happend to me before

His driveshaft goes into a gear box. He has a Merc sport drive. If it was leaking... it still wouldn't leak air... but it would fill the gears full of water.


As far as the wear ring... you need to check the clearance between the impeller an the pump wall. The tighter the better, but I'm sure as long as it's less than 0.040"... it should still work.

 

[NewFoundBoater]

2000 Islandia No power problem #2

OK, Here is the next saga. Checked the impellar and wear ring. Both were fine. The tech replaced 2 small fuel filters somewhere around the DDC but that did not fix the issue. Fuel pressure is now 40 psi. Once it hits above 3100 rpm cylinder 2 and 5 shut down. The stater and ignition switch have already been replaced. Now the tech feels that the trigger switch is the cause. He states that the last tech should gave replaced the trigger when the stater was replaced.

I welcome your thoughts?