Join Date: Jan 2001
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Atomic 4 Quits
We have a Newport 27 sailboat with an Atomic 4 engine (1976). With a 3 bladed prop 11 or 12" that alows the motor to spin about 2100rpms at 6.6 knots you can''t ever get above 2100 with this prop.
Anyway, the engine starts immediately, runs smooth except for the fact that the idle fluctuates between 600 and 2500rpms in neutral. Also, after running for awhile, sometimes 6 hours - 12 hours the engine quits and cannot be re-started for quite awhile perhaps an hour. This always happens at the absolute worst possible time. We almost got run down by a tanker in the entrance to Mobile Bay and had a interesting time getting into Perdido Pass against a 6 knot ebb when the engine quit. Needless to say, you don''t go far from the dock without getting your sails up immediately and knowing how to use them.
This engine is very well maintained. We disassembled and cleaned the carburator and wired out all the jets.
We''ve placed 2 fuel filters inline with the fuel system, we have a Borg Warner electric fuel pump that I believe is either 2 or 4 psi. We also have a fuel pressure regulator which regulates the fuel pressure to 1 psi. The cap, points and rotor have been replaced. It seems like every 10 or 20 engine hours we''ve replaced the coil thinking that it is overheating. With a new coil that has a ballast resistor, the old one did too. The points, cap and rotor always look like new inside.
We''ve gone over the wiring thinking there was a problem there. Now it just has a hot wired switch for on and a push button to spin the starter.
We are a wits end with this motor. We''ve had mechanics come out and they can find nothing
wrong with it. I''m considering trying a Pertronics unit in the ignition and a new Mallory oil filled coil as well as installing a fuel pressure gauge right before the carburator to make sure
that the fuel delivery is not wigged out somehow.Has anyone ever experience such a problem with their engine?
I''d really rather not put a Volvo MD2020 with a down angle drive in at the cost of $5500, but that may be the only way to make this problem go away.