Atomic 4

[Rick]

A couple of times now after after about 6 hrs of motoring, my atomic 4 (1982 Catalina 30) cuts out like it's run out of gas. It chokes and coughs a little, then goes back to normal and chugs on like normal. It has an electric fuel pump, and I'm wondering if maybe something is going on with that?

 

[Lou Van Essendelft]

Dirty carburetor

I had a similar problem with my 1983 C30. I removed the carburetor and found quite a bit of debris from the bottom of the fuel tank inside. I rebuilt the carburetor and also installed a fuel filter on the suction side of the fuel pump. Seems to have taken care of the problem.

 

[Rob]

Water Separating Fuel Filter

I had the same problem with my C-27 (still with the manual pump) and this is what I found.1 - "New Gas" (aka reformulated gas) is not as stable as old gas. Therefore, the old addage of keeping a full tank can hurt you more than help you. If you have 17 gallons of gas that is more than 4 or 5 months old, it can and will go stale on you. Stablilizer will help a lot, but it will not cure the problem. Which leads to No.22 - Not keeping a full tank allows for condensation, and the resulting formation of water falls to the bottom of the tank. When the boat sloshes around, as happens with a big wake or in choppy water, the water gets disturbed, gets washed up into the fuel intake (1/2" off the bottom of the tank), and then procedes to the engine. The past owner noticed that this will completely shut the engine down. This resulted in No. 3.3 - Water separating fuel filter. This unit is a good cheap fix. It is not as good as a globe type water separating unit, but it works great for my boat. Installation requires re-routing two fuel lines and bolting the fuel filter unit to the interior wall of the port wall of the engine compartment (as you face it). Now - how do I know all this stuff? The former owner had ancient gas in the tank. I experienced the same thing you did (even with the water-separating filter). Once it was bad enough to shut the engine down - completely. I could hear the cylinders rusting in my head!!The only solution was to completely drain the tank, allow to vent and evaporate, and then refill with new gas. I replaced the filter too, and have not had a problem since. Condensation is even worse when you sail somewhere with temp extremes. I also am familiar with this phenomenon in airplanes. I have a private's license, and one of my pre-flight checklist items includes "sticking the tanks" to check for water. Condensation in aircraft gas tanks is not just an inconvenience - it can be deadly. Hope this helps, and if you need any help, post and I will e-mail you. Best of Luck!Rob Rich