Hi Gang - looking for some advice
I have a 2008 Mercury 150 EFI
Motor is on an 1988 Champion Bass Boat.
I put the motor on new 3 years ago.
Initially the new setup ran like an all-star.
Really nice, smooth, turned up quick, got on a very controllable plane... all good.
Cruised 40mph up and down Apache and Powell several weekends.. all good.
One day I start getting the steady temp sensor alarm while mid-range cruising up the lake 35'ish mph.
.. I back it down alarm stops, check things out... got a telltale stream, I don't have a pressure gauge so..
... back up to speed / same routine.
got back tested sensors, changed water kit, blew out lines etc.
go back and this time the boat was lugging to get up, struggled to even get on plane.
I had a stainless 14 1/4 x 23 prop on it.
I pulled over put on a spare 14 1/2 x 19 spare prop... boat got up but the alarm thing returned a few miles up.
.. put in new plugs... no help.
Today I put the motor in a barrel and idled it up to temp
900 to 1,400 rpm worked the throttle a few times to get some heat.. 2,500'ish rpms
motor warms up, alarm goes off
I put infrared on heads and starboard was up (+ - 200f) , port was 130-140
Starboard top cylinder was hottest dropping 10-20 degrees as I moved laser down.
I'm going to take out the thermostat and check for any obstruction in the hose at the top of that head but I am not sure what the deal is.
Any advice or tests I should try?
I'm having boater blues and I want to get back on top again.
Thanks
I have a 2008 Mercury 150 EFI
Motor is on an 1988 Champion Bass Boat.
I put the motor on new 3 years ago.
Initially the new setup ran like an all-star.
Really nice, smooth, turned up quick, got on a very controllable plane... all good.
Cruised 40mph up and down Apache and Powell several weekends.. all good.
One day I start getting the steady temp sensor alarm while mid-range cruising up the lake 35'ish mph.
.. I back it down alarm stops, check things out... got a telltale stream, I don't have a pressure gauge so..
... back up to speed / same routine.
got back tested sensors, changed water kit, blew out lines etc.
go back and this time the boat was lugging to get up, struggled to even get on plane.
I had a stainless 14 1/4 x 23 prop on it.
I pulled over put on a spare 14 1/2 x 19 spare prop... boat got up but the alarm thing returned a few miles up.
.. put in new plugs... no help.
Today I put the motor in a barrel and idled it up to temp
900 to 1,400 rpm worked the throttle a few times to get some heat.. 2,500'ish rpms
motor warms up, alarm goes off
I put infrared on heads and starboard was up (+ - 200f) , port was 130-140
Starboard top cylinder was hottest dropping 10-20 degrees as I moved laser down.
I'm going to take out the thermostat and check for any obstruction in the hose at the top of that head but I am not sure what the deal is.
Any advice or tests I should try?
I'm having boater blues and I want to get back on top again.
Thanks
