'83 MC 260R bogs with trim switch?

[ToddK]

This sounded similar to other postings in that the boat runs fine the first couple of minutes then starts losing top end, but if I hit the trim switch up or down it bogs it down more of the same. Seems electrical condidering that. I put a new set of automotive plug wires and coil. Could it be the coil? I have Thunderbolt IV. Thanks in advance for your help! Let's hear you Mercruiser geniuses out there.

 

[Elk Chaser]

Re: '83 MC 260R bogs with trim switch?

It does not take much to power(amps) the ignition coil however if you have a short somewhere in the circuit it could take away the necessary voltage to the coil. I'd start with that. Start checking for a wiring problem at the trim pump and switches.<br /><br />You can also turn the ignition key on (motor off) and read the voltage at the coil. Have someone drive the trim pump and see if the voltage changes at all. It really should not change much. If it changes significantly then you have a problem somewhere. May have to do this again in the water, if the problem shows up in the water and did not on dry land then you may need to look towards the trim limit switch on the drive for the problem.<br /><br />That's a start.

 

[Bondo]

Re: '83 MC 260R bogs with trim switch?

I Agree with Elk Chaser......<br /><br />The Wires don't matter, <br />But,<br />The Coil has to be the Right One.....<br />This Could be a part of your Problems(Yes, I Think you have more than 1 Issue)......<br />

boat runs fine the first couple of minutes then starts losing top end

How long has it been since the Fuel Filters have been Changed ????<br /><br />You Might be starving for Fuel,+/ or Voltage.........