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Mercury 175 Blackmax Overheating

pasquale1968

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"Need some help guys At idle o

"Need some help guys At idle or just above there is very little water out the pee hole. Just steam coming from the motor. When we increase speed (2000 plus rpm) it pees good. When hooked to a hose at home i get water but not great pressure umtil i crank the rpm's a bit

When i run at speed or fast idle we can get water out the tell tale no problem. but if i'm simply trolling in the alarm starts to sound. Now my biggest problem is that i dont know the year of this motor, however thes are some of the numbers i was able to take off of the engine( the starter has a dat e of 1988, At the top of the engine thereswhat seems to be a freezeout plug with these numbers on it 0126471, and on the powerhead there is also a number that one is 858 8631-c4.i removed the thermostats thinking that would solve my problem but it didn't work, change the water pump twice and still the same. so i took off the lower unit checked to make sure the tubing going up into the block was clear and it is, i removed the heads and the exhaust passageways to look in and see if there was any sand or silt in there nothing clean as can be. Here's another question i noticed at the base of the engine there is what looks to me like some other type of tstat housing is that the poppet valve it has alot of salt creep on the bolts and i'm trying my best to figure this out. If you can help it would be greatly apreciated thanx alot in advance PAt"
 
That should be the pressure re

That should be the pressure relief vavle (poppet) make sure it isn't stuck open dumping off water that should be cooling the engine.
 
"Thanks rollie rose . still go

"Thanks rollie rose . still going crazy with the year however i managed to find the clymer manual that came with the boat, only problem is that the date range is 1990 to 1993 and i wish i could find some type of number to be able to identify it for when i purchase parts. Any Suggestions would be gr8 Pat"
 
"Zollo,
Just a question, is t


"Zollo,
Just a question, is the impeller key in place holding the water pump impeller so it doesn't slip?"
 
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