good impeller/lowpressure

[specboatops]

This is going to drive me crazy, 1994 Merc 2.5 200 efi, motor has the thermostats in. I am barely getting pressure from my pee tube, not pluged,gauge is reading a little low, around 6 to 8 at idle but then will drop to
4 or so, impeller is fine,and at times i am showing pressure on my gauge(gaffrig) and there is NO water coming out of pee tube...........help!

Chris

[bill mason]

go up where hoses go into heads. Remove both the thermostates from the housings. Bothe the housings back on and see if water comes out. You have something blocking water flow. If the thermostats don't do it you are going to have to remove heads and check wter passages, last thing will be the water outlets in the exhaust plate. Good luck,

[MadTing]

Check the poppet valve for sticking or a torn diaphragm.