Hot water coming out of motor?

Discussion in 'Boat Tips' started by Chief, Jun 29, 2006.

  1. Chief

    Chief New Member

    Messages:
    261
    State:
    Indiana
    i was wondering if the water that streams out of the motor is supposed to be hot? its not boiling hot or anything just a little hot. also i noticed the top part of my lower unit the part NOT in the water is kinda hot to the touch as well. is this all normal or is it water pump rebuild time?
     
  2. TxRiverman

    TxRiverman New Member

    Messages:
    324
    State:
    Lockhart Tx
    water pump or the impeller
     

  3. DeerHunter01

    DeerHunter01 New Member

    Messages:
    2,113
    State:
    Kentucky
    Chief: I had a 40 HP Merc and when I hooked the ears up to it to run it at home the water would be Hot ( Warm to touch) not burning hot but you could hold your hand in it, as long as the Pee hole is streaming water you should be fine.

    Now with my 150 Merc that I have it takes a little longer to get the water warm and it has to be out on the river when running it to get warm water to come out of the pee hole, and every time I bring my boat back to the ramp and load it as I put the transom saver on I always touch that engine and the top part of the bottom unit is always warm to touch but you can hold your hand on it with no problem. I think this is normal, but if it quits peeing your in trouble, as long as you see that water coming out you should be good to go.


    I have my water pump replaced every winter on my boat just for preventive maintenance and change the lower unit oil, and spark plugs .
     
  4. borntocatfish

    borntocatfish New Member

    Messages:
    309
    State:
    NW ohio
    Sounds normal it supose to be hot but not burning hot more like warm hot
    but make sure the lower unit isn't burning hot or its time for more gear oil
    :0a26:
     
  5. catseeman

    catseeman New Member

    Messages:
    1,189
    State:
    Indianapolis, Indiana
    Chief, that's the water's job to remove heat fom the engine. as stated above (If its flowing you are going.)
     
  6. shortbus

    shortbus New Member

    Messages:
    459
    State:
    indiana
    The lower unit gets hot from friction and the exhaust running through it. It should be warm but not super hot. The water coming from the engine should be warm also. When it's warm you know the water is pulling heat out of the engine to keep it cool like it should. Something like how a radiator works.
     
  7. Chief

    Chief New Member

    Messages:
    261
    State:
    Indiana
    alright! sounds like i'm finally ready to hit the river. thanks for the help
     
  8. Abu65

    Abu65 Member

    Messages:
    582
    State:
    Kentucky
    Yes, its a heat exchange system, the heat is leaving the motor via the water.
     
  9. heeler

    heeler New Member

    Messages:
    64
    State:
    missouri
    If it ever starts steaming,your in trouble
     
  10. Fishgeek

    Fishgeek Active Member

    Messages:
    1,149
    State:
    Indiana
    We have 25hp Mercs at work & they do the same thing. Water's nice & toasty. I often use it to warm my hands after they've been in the tub measuring fish on those cold spring nights!
     
  11. WylieCat

    WylieCat Well-Known Member

    Messages:
    7,160
    State:
    NC
    Warm water is good.

    NO WATER IS BAAAAAAAAAAAADDDDDD!

    Thats what keeps the motor cooled down, so it will be a little warm.
     
  12. catfishrus

    catfishrus New Member

    Messages:
    1,569
    State:
    north carolina
    i think the newer model motor have thermostates in them and it may take longer to get the water flow to start. i know my mercury 175efi takes a while and it seems warmer compared to other boats i have owned. i had the water pump replaced in mine this year because i thought something might be wrong but the old one was still in good shape. i was told there is a by pass value that opens at full trottle on the newer models.