mercury 45 hp loss of power

bob proudfoot · #1 February 18th, 2009, 09:58 PM

To anyone ,We have a 45 mercury that we have loss of power in the water at full throttle.It did run at full throttle for about 20 min and then shut back down to half speed . all plugs are firing ,switched the stater wires and no change.We haven't checked the oms on the trigger yet but thats the next step.It could be the switch box but not sure.We were thinking it could be the fuel lines but the motor starts and runs good at idle and at half speed.are there any suggestions out there to help us.We would appreciate any suggestion. Thanks

tashasdaddy · #2 February 19th, 2009, 05:12 AM

serial #, did it run hot? have you checked compression, vent on fuel tank open????????

bob proudfoot · #3 February 19th, 2009, 09:30 AM

Quote:

Originally Posted by tashasdaddy

serial #, did it run hot? have you checked compression, vent on fuel tank open????????

It ran cool, compression 100 or better on each cylinder,vent open.

Laddies · #4 February 19th, 2009, 10:00 AM

Did you try pumping the primer bulb to see if the fuel pump was OK? I would need test the trigger but I think you will find it OK inless it has a damaged wire. Chances are it's a bad box which can not be tested except with a DVA to test input and output.

bob proudfoot · #5 February 19th, 2009, 07:58 PM

yes we pumped the gas up while we were running and it didn't make any difference. We are going to check the fuel lines and then the oms on the trigger and go from there.There could be a small line at the motor not letting the gas to get to the engine. I hope its not the switch box but possible.It would be our luck and it would cost more. Thanks for the suggestion.