this is my first time posting a question i have an early 90's mercury black max 175 hp that overheats i believe i have read every thread here but have not been able to solve my problem. i have replaced everything i can think of trying to solve this, water pump base, impeller, upper housing, water pickup tube, base gaskets on top and bottom of base plate, poppet valve, head gaskets, and stats. still have the problem this outboard runs great compression is 124 to 127 on all six cylinders. currently i am running with no stats and no poppet valve yes i have noted all the warnings of running with no stats now to the problem this outboard runs 40 to 50 degrees hotter on the starboard or poppet valve side with the poppet valve installed it will reach over 300 degrees on the poppet valve side (some more info my water pressure at the top of the block varies between 3 and 25 psi with the poppet valve installed and at 3 to 10 psi with no poppet valve as i am currently configured i have removed the stats and poppet and can at least use the boat but the poppet side head temp runs 170 to 190 degrees still seems to hot to me the port side stays a 130 to 150 degrees this is determined by a ir heat gun at the lake this block has a water fitting at the top of the block my pressure is read there then a hose runs from that top fitting to the stat housing on the poppet side which is a "t" and a hose runs from there to the other stat housing and a final hose runs from my poppet cover the the telltail i have tried running a hose from the top fitting to a "t" connector between the stat housings then a hose from the poppet side housing to a "t" connector in the hose from the poppet to the telltail but it runs hotter when configured that way my telltail stream is not what i would consider strong but it is steady oh i forgot to mention i also changed the exhaust divider and cover plate gaskets no change sorry for the long post but alot of what i see in the answers here is "we need more information" any help or suggestions would be greatly appreaciated i guess my question is how is water routed to the poppet valve? the only thing i can think of is some kind of blockage in that path way that does not allow enough pressure to open the poppet when installed nor allow enough water flow when running without one needless to say this is driving me nuts thank you terry
if anyone cares to answer by email i am: terryb@rjbservices.com
if anyone cares to answer by email i am: terryb@rjbservices.com