Merc 454 Cutting off and on**Please Help*

[J Reilly]

Hello, I have a 92 Maxum with a Merc 454 Bravo, Thunderbolt ignition. Boat starts fine, runs great, temp sits around 150-160. Just replaced (last week) the water pump, water therm housing, therm, alt, plugs, cap and rotor and the coil.

Now the problem is: after running for a little while, 30 min, the engine will start to drop RPM's, and when I back if off, the engine will die... wait for about 10 15 min... engine fires back up and will run fine...

I cant figure it out... Thought it was the coil but its brand new... Any help would be great.
Thanks

 

[jerryjerry05]

Re: Merc 454 Cutting off and on**Please Help*

Sounds like a fuel problem.Check all hoses and vent lines.Ethanol has been messing with a lot of things.It melts the inside of the softer hoses and can clog.Check the filters.You have a water/fuel seperating filter?You should install one.J

 

[Blk-n-Blu]

Re: Merc 454 Cutting off and on**Please Help*

Agree with jerry. When it happens have a look into the carb (if it has one) and see if it is getting fuel. If you have an electric fuel pump a possible cause could be the oil pressure switch shutting down the pump, Is the oil overfilled?