Chevy 350

Discussion in 'Powerboats' started by mikealston2428, May 25, 2012.

  1. Frosty

    Frosty Previous Member

    Your post said you noticed no water why would there be 500' from the waters side.
     
  2. IMP-ish
    Joined: Jan 2011
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    Location: united states of america

    IMP-ish powerboater

    Hose from spigot.
     
  3. Frosty

    Frosty Previous Member


    Then the impellor was lubricated by the water.
     
  4. IMP-ish
    Joined: Jan 2011
    Posts: 389
    Likes: 9, Points: 18, Legacy Rep: 150
    Location: united states of america

    IMP-ish powerboater

    Having a spigot on the wall doesn't make the water flow to the outdrive by itself!
    No water.
    I've done other stupid things.
    I once put a boat in with no drain plug. Yea, the age old marina "did you check the drain plug" and I still forgot it once. This one I lucked out. Also lucked out when I left the drain plug out but that's another story.
     
  5. Frosty

    Frosty Previous Member

    Don't run an engine out of the water or without supply it says so on page one.
     
  6. Carteret
    Joined: Jan 2004
    Posts: 119
    Likes: 6, Points: 18, Legacy Rep: 137
    Location: Eastern NC

    Carteret Senior Member

    I had one one time that was hard to start due to fuel siphoning back to the tank. The ramp angle actually aggravated the problem. I installed a check valve in the fuel line and the check cured the problem
     
  7. Frosty

    Frosty Previous Member

    Then your fuel pump was the problem. The pump itself has 2 valves.

    No system can siphon back the fuel in the float chamber, and there should always be enough there for the accelerator pump unless the vehicle / boat had been left a looong time.

    The Accel pump takes fuel from the bottom of the bowl so there should always be fuel to pump and keep it going until even a bad pump and dry pipe could catch up.
     
  8. midnitmike
    Joined: Apr 2012
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    Location: Haines and Juneau

    midnitmike Senior Member

    Hi Mike,
    The 32' Uniflite I have in the yard has two of these 350 chevy's in it, so I can empathize with you. Although I picked the boat up for the salvage cost after it sunk last Winter I did have the "pleasure" of being aboard her on a number of sailings with the previous owner over the last few summers. Other then the normal unreliability that you get with gas engines I have to admit that they had more then their fair share of carbs problems thanks to the installed Quadra Jets.

    First let me say that pumping the "Choke" won't induce gas flow into the carb...all you're doing is opening and closing the choke plate. If the engine is cold and off the choke should be closed...you'll have to manually open the choke to see into the carb throttle body. With the choke open either have a friend operate the throttle control or disconnect it from the carb and do it yourself. With each movement of the throttle you should see gas being squirted into the engine intake manifold. You don't have to do this more then once or twice to know if your accelerator pump is working. If it is then you can move on because that's not your problem.

    In your previous post you mentioned that the engine was hard to start and required fuel being poured into the intake, now you're reporting lots of black smoke and soot as well as poor performance. Both are indicitive of a malfunctioning choke. In one instance it's stuck open and requires lots of fuel to get started, and the next it's probably stuck closed causing all that black smoke. In either case I'd recommend you have a mechanic look at it because it's not going to get better over time.

    MM
     
  9. PAR
    Joined: Nov 2003
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    Location: Eustis, FL

    PAR Yacht Designer/Builder

    You are leaking down or suffering from evaporation loses with your hard starting situation. Fuel should remain in the bowel for quite some time (months) without leaking out or evaporating off. This is especially true of marine carbs.

    This suggests you have something amiss in your carb or fuel delivery. The issues seems to becoming compound, so take it to someone who knows marine carbs, for a diagnoses.

    I suspect you have multiple problems, all minor, but combined causing several issues, such as hard starting, poor performance, poor fuel economy, rough idle, etc. It's likely a simple tune up will cure most of the problems if coupled with a fuel system checkup.
     
  10. Frosty

    Frosty Previous Member

    The bi metal thermal choke adjustment is critical. 3 screws and you can turn it increasing or decreasing spring effect on the choke flap. It should not be so strong that it wont come off.

    A fine point in the middle is whats required. There is a vernier guage marking so you can see what you have done.
     
  11. tunnels

    tunnels Previous Member

    Stern drive is like a outboard So no leg in the water the pump will die very quickly and yes you have a heat exchanger and a closed system it is possible to run the motor but have to disconnect the drive shaft at the back . Lots a work just fit some ear muffs and be done with it of !! or you could try one of these ok for out boards and also sterndives . DONT PUT IT IN GEAR !!! COLLAPSABLE AND CONNECT THE HOSE AND IT FILLS AND HAS A 3 LEGS THAT ARE JUST TO HOLD THE TOP RING UP THATS ALL :confused:
     

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  12. PAR
    Joined: Nov 2003
    Posts: 19,133
    Likes: 477, Points: 93, Legacy Rep: 3967
    Location: Eustis, FL

    PAR Yacht Designer/Builder

    Okay Tunnels, I think we've covered the importance of immersed water inlets on the drive leg.
     
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