2004 efi cooling problem

[sleeper bird]

iv got a 2004 200 hp efi 265 hrs when taken in and had a solid alarm at idle.sent it in to a merc dealer and they said water pump.had that changed(which i dont think the water pump i had was used maybe 10 hrs)upon first start up had abut 13 psi at idle as the day went on noticed it was dropping to 5-7 psi in gear idling.got in a long no wake zone maybe 1/2 mile alarm goes off still peeing about 5 psi pressure put it in neutral brought idle up to 1200 rpm and alarm turned off.It only seems to run hot idling in gear.What am i missing here?im thinking about getting smartcraft guage if it has actual coolant temp.Oh and thermostats are new oem

[JOE54]

were all 3 gaskets changed,not 3.0L is it ?? got ser num

[sleeper bird]

made a mistake was manufactured in 2001 i believe its a 2.5 liter,serial number is ot467866.All i see on receipt is water pump kit.Thanks for the reply

[JOE54]

id have too return to dealer and request do over for same problem without wait sure sounds like something wrong in pump mabe gasket under base, please report back

[sleeper bird]

i sure will,can i add another question,the motor is smart craft technology.I have analog guages,tach,fuel and such.I would like to add the smart craft guage to keep an eye on actual engine temp.I noticed that at the front of the engine there ia a cable with a square plug and about 3 ft of lead wire is that where the smart craft connects?and will i still retain my analog tach guage if using the digital version?

[JOE54]

think that's for other sensors like oil tank and fuel tank,should be another plug end close to pcm with resistor cap yes analog will still operate

[sleeper bird]

Thanks Joe

[JOE54]

welcome

[sleeper bird]

i found something today while running my cable for smartcraft,and rebuilt poppet valve(just because) i decided to pull the temp sensor out and noticed it was loose,pulled it out cleaned the end and went to put it back in and with very very little resistance it kept spinning,removed it and it was snapped off,im thinking it was cracked and loose and got me wondering if this could be the cause of my cooling issue,maybe false signal

[sleeper bird]

update,after changing the two top temp sensors i took it out,iv also ran a smartcraft guage to keep an eye on the temperature. at idle the temp keeps creeping up until it hits 185 and alarm goes off idle it up and temp immediately goes down,if i idle it at 1100-1200 rpm temp stays 125-130 on plane and pushing it it seems to be anywhere from 118-125.i noticed that when it does idle at around 800 rpm the water pressure gauge bounces from 8-5 psi,on plane about 12 psi.I ordered every single part of the water pump including the plastic upper and lower housing and am going to pull it down myself and see what i see, thermostats were changed last year,new plugs, wires,rebuilt poppet ,two upper temp sensors(the plastic ones that screw into the head)before i do anything else im going to run it on the hose and see what happens.

[JOE54]

post result in v6 section one down with ser num,remember on hose your forcing cool water in it JOE

[sleeper bird]

sure will but i was assuming being that my engine is stock i thought i was in the right place

[aussiejake]

,two upper temp sensors(the plastic ones that screw into the head)

I may be wrong but the plastic ones are only for atmosphere air temperature for the smartcraft gauge, not for the motor.

You need the brass temperature senders that screw into the head. The 2 head sensors and the intake plenum air temp sensor are all the same and are brass.

[SilverFox579]

sure will but i was assuming being that my engine is stock i thought i was in the right place

The 2.0/2.4/2.5 forum is right place. Have read there's apparently a potential issue with changing forum titles and search features. Was confused about that shortly after joining BBC too.