I/O running temperature

[bombay]

I recently bought a 1982 V20, my first boat. It has a 170 hp Merc. that seems to run great. I notice that the temp. jumps to about 180 pretty quick then stays at about 200-210. Is this a normal temp or a little warm. I plan on changing the water pump as I don't know when the last one was put in, but am leary of running too hot in the mean time

[WiseGuy]

Had the same deal - got towed in. The water pumps (impellers)are only good so long. The parts kit, which includes the housing, on mine were $55. Labor extra and involves taking off the out drive (it's inside). Good to go now - Might put in a new thermostat for cheap while your at it.

[charlie_the_tuna]

sounds pretty hot to me. my i/o runs at about 130-150 all day long.

[revmax]

Mine runs cooler than that also, about 160 or 180, I forget the no. on the thermostat. I was told tho that if you keep it cool it helps cut down on the salt build-up. I would suspect something because I doubt you have a thermo rated that high.

[LESTERUS]

MY V-20 ORIGINALLY HAD A 470 MERCRUISER (170 HP.)
THAT USUALLY RUNNED VERY HOT, SINCE THAT ENGINE IS FRESH WATER COOLED. NOW CHANGING THE IMPELLER IS ALWAYS A GOOD IDEA WETHER YOU USE THE BOAT OR NOT.

IF THAT IS THE ENGINE YOU HAVE (470 MERC. 170 HP
4 CYL.) MY ADVISE IS GET RID OF IT AND REPLACE IT IF YOU CAN WITH A 4.3 MERC. SAME OUTDRIVE RATIO
SAME HP (175 HP AT PROP.) I DID IT AND IS A GREAT ENGINE, VERY,VERY,VERY ECONOMICAL.

THE 470 IS A GOOD ENGINE, BUT BEING A 4 CYL. WITH BIG (5.250") PISTOS IS VERY DIFFICULT TO TIME IT SPECIALLY WHEN OLD, AND THE PARTS ARE VERY DIFFICULT TO GET BECAUSE IS A MIXTURE OF DIFFERENT ENGINES, PISTONS ARE FORD, VALVES ARE GM, PAIN IN THE NECK.

LESTERUS

[CT_V-20]

Owners manual on my 5.7 Mercruiser says 160 degrees. I was running hotter and had a new thermostat (i think 140 degrees) put in and a couple barnacles in the intake cleared. runs perfect now. I was running +200 prior to the fix and that's too hot for my engine.

[rb437]

more info on this recent thread

http://www.wellcraftv20.com/cgi-bin/yabb/YaBB.cgi?board=Performance;action=display;num=1150 681662

[WiseGuy]

Hey 76GMC1500,

Why do you want the engine to run on the hot side? Curious as to the mechanics behind that. Thanks

[Skools Out]

Hotter will keep you from fouling plugs but can be hard on the heads.