#1
IP: 72.43.60.181
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Atomic 4 Symptoms~I'm Stumped
Don~
To refresh your memory. We chatted a few days ago vai phone regarding an issue with my Atomic 4 which starts immediately, runs beautifully for about 1-2 minutes then fades and stops with a bit of stress, almost as if it was about to seize. Amazingly, she will start immediately and repeat the same process, however the run time becomes shorter and shorter unless she has about a minute or two to recover. My temp gauge indicates she is not running hot. I have no history on the engine and boat (Catalina 27) as I acquired it from a local Rockport Maine YMCA auction in the summer of 2006. Over the winter (2006-2007) I removed the engine from the boat and together with a friend we replaced the exhaust manifold (which had a crack). The block and cylinders looked amazingly clean with very little wear. The valves were ground and seated, the tappets cleaned and adjusted, thoroughly cleaned the water ways and replaced all gaskets. The carburator was cleaned but we did not replace any parts. New plugs, wires, rotor, condenser, coil, hoses, exhaust pipe. Most all essential parts were either cleaned and or replaced. The compression is at or above 100psi on all four cylinders. Oil pressure indicated is about 40-45 lbs and is level and consistent. I've removed the screen from the gas tank (which was very clean) and have a fuel filter in line. The timing is right on the money. When started, the engine runs superbly and when given the throttle-up she revs up perfectly. Then she slows down (as is a load was on the engine) and stops. There is a little oil smoke too. But as mentioned, she cranks up again immediately without issue. We've checked the neutral position to make sure she is running freely each time (boat is on stands in my home driveway). Uggh! We are really stumped. What could it be? Last edited by Herron; 09-07-2007 at 05:29 PM. |
#2
IP: 72.200.13.154
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Check the carburetor (float could be stuck) it could be flooding from electric fuel pump. Just a maybe..
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#3
IP: 206.181.246.34
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Sounds like fuel starvation to me.
Jim |
#4
IP: 72.71.249.221
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Even though it may sound like a fuel starvation problem, you may want to consider to other issues.
First, you may have a bad condensor.....even though it may be new, they still can be bad Second, the switch.... in the old tractor world, switches are the cause of more frustration than you can imagine, simply because nobody thinks of then a failing. Do a complete check on your fuel flow, if that fixes the problem great, if not try the items above. David |
#5
IP: 207.34.223.165
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Check to see if your oil pressure switch is functioning properly, if not connected or not functioning, it will kill your electric fuel pump (assuming you have one). I had this problem a year or s back, engine would start fine and run fine for a couple minutes then die, then start up fine and repeat the cycle until I found a wire on the switch was disconnected. When starting, the fuel pump fills the carb (powered by the ignition switch), the engine starts and the unconnected oil pressure switch fails to maintain power to the fuel pump after starting, the engine uses up all fuel in the carb float chamber, and dies after a couple minutes. Shorting the oil switch is an easy test of this problem.
Bob (s/v Saga) |
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