Volo Penta Pump Problem

Discussion in 'Diesel Engines' started by Katoh, Dec 10, 2010.

  1. Katoh
    Joined: May 2010
    Posts: 205
    Likes: 2, Points: 0, Legacy Rep: 58
    Location: A.C.T

    Katoh Senior Member

    G'Day All
    I have recently acquired a vessel with a ad31b and 290SP leg Volvo Penta.
    My problem begins with the raw water pump from the the leg, I placed a set of Flushes or earmuffs over the intake on the raw water intake of the leg. off course connected to hose on mains pressure. Start the motor and there is no water out letting from the leg at all.
    I removed the the flilter from above the pump and tried to pump water in reverse with the hose to no avail. I tried from the outlet of the filter with the hose and instead of water exiting via the exhaust it was escaping from somewhere else, I could not see were. The pump seems to be working on the front of the motor but there is no water going anywhere.
    My understanding is that the raw water should be pumped up through the leg to the water pump then through the heat exchangers and exit via the exhaust.
    This is my first stern drive in the Volvo Penta, and information is difficult to come by.
    Another quirey when in neutral the prop still turns, I have tried different lever positions but you cant start it while in gear is this normal?
    Cheers
    Katoh
     
  2. gonzo
    Joined: Aug 2002
    Posts: 13,771
    Likes: 431, Points: 93, Legacy Rep: 2031
    Location: Milwaukee, WI

    gonzo Senior Member

    There should be a small hole in the bottom front of the outdrive. You need to plug it so the pump doesn't suck water. Volvo Pentas are notorious for being difficult to prime with a hose. You are better off disconnecting the hose and connecting the water supply to the pump intake. If you run the engine for long with no water pumping, the impeller is probably damaged. The exhaust hoses may be damaged too. Also, it should never start in gear. There is neutral safety switch to prevent that.
     
  3. Katoh
    Joined: May 2010
    Posts: 205
    Likes: 2, Points: 0, Legacy Rep: 58
    Location: A.C.T

    Katoh Senior Member

    I haven't run the motor for long at all, the first thing I checked for is water pumping and once nothing was coming out I switched it off. were exactly is that hole located, I have gone right over the leg and could not find any holes at all. I think I am going to have to pull the motor and leg out, and give them a rebuild.
    thanks
    Katoh
     
  4. gonzo
    Joined: Aug 2002
    Posts: 13,771
    Likes: 431, Points: 93, Legacy Rep: 2031
    Location: Milwaukee, WI

    gonzo Senior Member

    If it is one of the old style legs, there is a small round hole in the front bottom. The pump is at the front of the motor. One of the problems is with bad sealing on the water pickup. With the boat out of the water, the pump will suck water and not prime. Even in the best conditions, those engines have a hard time getting water from a hose. Why don't you try the boat in the water?
     

  5. Katoh
    Joined: May 2010
    Posts: 205
    Likes: 2, Points: 0, Legacy Rep: 58
    Location: A.C.T

    Katoh Senior Member

    I removed the water inlet from the pump and put the hose in backwards, I soon found the hole your talking about . it was on the back off the drive right down the bottom facing the road.
    Before reattaching the the hose to the pump I plugged the hole, put on the earmuffs to see if I could get water up to the pump , which I couldn't. so I used another hose from the pump inlet and attached the hose to that, started the motor and it pumps water, looked at all the leeks and thought doesn't matter as I'm going to remove both motor and leg for a rebuild.
    I don't want to put the boat on the water as there are a couple of places of corrosion on the hull that need repair.
    Cheers
    Katoh
     
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