Atomic 4 dies in gear...

[August West]

Hi All,

I've got an old Newport 30 with an Atomic 4 in it. I can get it to run, however at idle it struggles and when I put it into gear it dies, no matter what. I can limp it along partially(?) in gear but it takes a lot of tweaking. I cleaned out the flame resistor and I THINK the next step would be pull and clean the carb. I am hoping that maybe I can just do some adjustments to the carb to get it in shape.

Any, any advice would be greatly appreciated.

Thanks in advance,
August

[Me-and-Boo]

A guess is your ignition system is in need of TLC. Points and condensor would be a beginning before pulling the carb. You might want to replace the springs if those are still originals.

[CaptainMurph]

There are many suspects here, but I would start with the fuel system.

If you have the original engine-driven fuel pump (port side of engine), pull the sediment bowl and see if there is junk/water inside. If it is clean, I'd pull the carb and inspect the float bowl. You can have gunk that will only get pulled up when there is more fuel demand.

If you don't see any water or crud in the fuel system and have replaced your fuel filter (assuming you have one between the tank and inlet to the fuel pump), you should check basic igintion tiiming. If it is retarded too much, the engine will start easily and then not want to run with any throttle opening or torque demand.

You might also want to check with the forums at www.moyermarine.com

Murph

S/V Amalia
1965 Cal 30

[rbyham]

Have you found the A4 forum over on Moyer Marine? That group is great at solving challenges like this.

[perchance]

What is your idle rpm?

[appick]

I'd agree with the fuel system. The carbs can get gunked up so quick with sediment and varnished fuel its not even funny. What year is your boat and engine? That will determine what carb you have. Read up on how to properly clean and disassemble and reassemble these carbs and clean it all. You can't get it clean without removing it from the engine and tearing it down. A can of carb cleaner will not do the trick with the carb still assembled.

Once you get the carb cleaned up read up and pay attention the the proper adjustment procedures and get the carb and engine dialed in correctly. This will save on fouled plugs or running too lean and burning a valve.

Also if your boat doesn't already have it put an electronic ignition kit ($265 at Atomic 4 - Indigo Electronics, Inc.) on it if you can afford it! I don't work for them just an awesome resource for all sorts of great updates to your engine. This will save you lots of fiddling with points and inconvenient break downs when they go bad... If you can't afford it no sweat just check the adjustment and condition on the points and test your capacitor. Then follow recommended maintenance on these.

I have a 1961 boat that probably has a 1958 engine in it. After replacing the fuel filter and "cleaning" the carb several times it still wouldn't idle quiet right. I realized that due to my cast steel float bowl there was rusting happening in the bottom of the bowl. I scrapped and brushed until it was good and clean. I then went and cleaned every orifice and tube. It turns out the bottom of my idle tube was completely packed with rust sediment. It now idles smoothly and delivers plenty of power.

In short, like almost all engines, they are great and very reliable when properly maintained and will last a very very long time.

[cal40john]

Another place to check is the spark plugs. Getting the hot ignition kit cut down on having to clean the plugs.

[S/V Alchemy]

Originally Posted by appick

In short, like almost all engines, they are great and very reliable when properly maintained and will last a very very long time.

Total agreement here. Atomic 4s have a problem in that they can be screwed up in a number of ways before they actually give signs they are "suffering". Carbs and that mechanical fuel pump are prime spots for goo/debris. Proper maintenance can include not only the occasional clean out, but also a carb rebuild kit.

A "tune-up" involving new distributor cap, new spark plug wires, new (and maybe the hotter RJ12YCs gapped to .040") plugs, maybe a new coil (if old-school) can, when the fuel is clean and the carb is de-crudded, yield near-miraculous improvements in quick starts and torque to the prop. Join the Moyer forums: all will be revealed.