Restoring Atomic Energy

A 12-step recovery program for venerable gasoline inboards

By Capt. Alan Ross Hugenot

Universal Motor Co., founded in 1898, no longer manufactures the Atomic 4, but a complete aftermarket of parts distributors and engine rebuilders has grown up to support this engine. You’ll also find several enhancements available to solve nearly all this engine’s minor challenges -- including add-on kits for freshwater cooling and electronic ignition systems.

Some owners have opted to repower their boats with an exact replacement diesel engine now built by Universal, which can be easily changed out for an older gasoline Atomic Four. However, even if your old Atomic Four is barely breathing, there may still be life in it — if you give it a complete tune-up. The same advice holds true for owners of other older gasoline engines.

Here is some advice for rejuvenating these engines. The information presented here is equally useful for any other gasoline-powered marine engine -- and except for information on the ignition system, it also will generally apply to marine diesels.

With the proper propeller for the gear ratio, and when properly mounted in the hull, a marine engine -- whether gasoline or diesel -- needs only four things to operate: a clean fuel and air supply, ample clean lube oil, enough clean cooling water and proper ignition. Of these four, it is often the ignition system that fails first. A tune-up is the answer to keeping it going.

With any gasoline or diesel boat engine, maintaining the electrical system is always a challenge, especially in the damp marine environment. The ignition system is the part of the electrical system that generates a spark at just the right moment to fire each cylinder. It consists of the ignition switch, the ignition coil, the distributor and the spark plugs.

The engine is often mounted in the lowest part of the bilge. Even in the driest fiberglass boat, there is usually some water under there that vaporizes with the engine heat, rises onto the engine and then condenses as the engine cools. This dampness can quickly destroy an ignition system.

The first step in protecting your ignition is to eliminate dampness in or near the engine compartment. Otherwise, you will often have to disassemble and dry out the ignition system and remove all the crystallized salt on any bare contacts before you can start the engine.

The second step is to perform a proper tune-up on the ignition system. A good time to do this is during your annual spring fitting out routine. You’ll want to set the distributor points, cleaning and reset the spark plug gap, and, if needed, replace the condenser, rotor, distributor cap and coil.

Shopping for all the proper parts to perform this annual ritual can be time consuming, but some companies make things easier by offering complete tune-up kits for specific engines. An Atomic Four tune-up kit containing plugs, points, a condenser, a rotor and a cap is available for $45 from Moyer Marine — and the company also sells a complete service and overhaul manual.

Tuning up an engine’s ignition system is a simple process — if you collect the right parts, assemble the proper tools and allow plenty of time to do the job. When you are finished, your properly tuned Atomic Four can give you many more years of economical performance. On the other hand, unless you learn the few simple techniques required, you could find your boat dead in the water.

Today, most boaters have never performed a tune-up on an ignition system. However, a couple of decades ago -- before electronic ignition and fuel injection systems became common on automobile engines -- almost everyone knew how to do a tune-up.

The first time you tune an engine, it will take you most of a Saturday. Later, after you learn the ropes, you’ll be able to finish the job in about two hours.

For those of you who would rather spend your time cruising instead of doing an annual ignition system tune-up, there are two other options: Indigo Electronics has created an electronic ignition system conversion kit for the Atomic Four, which Moyer Marine can supply; or you can hire a marine mechanic to tune your engine each year.

Here’s everything you need to know to perform a complete ignition system tune-up yourself, in 12 easy steps:

1 — Remove the distributor cap. Pop off the hold-down clamps and remove the cap, with the wires still attached.

Next, locate the wire from Number 1 cylinder’s spark plug. Remember that Number 1 is the one closest to the flywheel, and this is usually the one that is farthest forward.

Notice that there is a keyway that only allows the cap to fit on the distributor in one position. The spark plug wire from the Number 1 cylinder should come into the cap at the pin located near this keyway. The rotor will be in that position when the Number 1 cylinder is supposed to fire.

Next, turn the engine until the rotor points to the keyway slot in the distributor body. The crank pin on the end of the flywheel should now be straight up and down, and the Number 1 piston is all the way to the top of its compression stroke. Mark the position of the distributor body with a piece of chalk. This will tell you if the distributor is back in the right position when you are finished with the tune-up.

2 — Remove the rotor. Remove the rotor by pulling it straight up and off. Take the little felt oiler from the center of the shaft. Wash it separately in a cleaning solvent, such as kerosene. Now, your way is clear to get to the points.

3 — Check the points. If you find any pitting on the contact points or rust on the spring, replace them. I usually do this every time. Since you have invested part of a day to get this far, it would be false economy to not replace a $12 set of points and a $6 condenser.

4 — Install the new distributor points and condenser. Unscrew the existing condenser and replace it with a new one. Remove the old points and install the new set. Replace the wick in the top of the shaft and add several drops of oil.

5 — Adjust the distributor points. Align the fiber block on the points with one of the four highest lobes on the cam in the distributor. This places the points in their maximum open position. When they are properly adjusted, a 0.18 inch feeler gauge inserted between the open points will move with just a slight drag.

6 — Install the new rotor. Simply place the new rotor on the shaft.

7 -- Cold-set ignition timing. Unless the engine is disassembled for major repair work, retiming of the ignition should not be required.

Remove the cover from the starter drive on the flywheel cover. Rotate the engine until the crank pin in the flywheel is vertically in line with the timing mark on the flywheel cover. When they are lined up, the Number 1 cylinder is in the optimum position for ignition, and this is where the points should open for Number 1.

If the points are not open, loosen the distributor clamp at the distributor base and turn it counter clockwise until the points just begin to open. Check to make sure the rotor is pointed at the Number 1 spark plug terminal.

8 — Install the new cap. Mark each spark plug wire with a piece of tape. Number them all, 1 through 4. Remove the wires from the old cap, and re insert them in the proper holes in the new cap. Place the new cap on the distributor body and clamp in place.

9 — Check the ignition coil. If it is just slightly oily, it can be cleaned in place with any low-residue solvent. On the other hand, if it is rusty, remove it and clean it with a wire brush and renew the outer paint coating. Often, it is just easier to replace it with a new one (they cost $26).

10 — Check distributor wires. If the wires are stiff, cracked, brittle or worn, it is time to replace them. A new set is only $20.

11 — Set the spark plug gap. Remove the spark plugs. If they are carbon-fouled or look worn, or if the white part of the insulator nose has turned a light brown, it is time to replace them. Atomic Fours need Champion RJ12C ($9 a set of four) or another set of the same type, with the gap set at 0.35 inch.

12 — Warm-set ignition timing. Since we did not remove the distributor itself, the timing is already rough set so the engine will start and run. Start it up and let the engine warm up, running at 1,500 rpm in forward gear for 20 minutes, while your boat is secured with docklines.

Loosen the distributor clamp. I usually loosen this before starting the engine and then lightly hand-tighten it.

Advance the timing by turning the distributor body counterclockwise until the rpm begin to fall off. From this position, carefully turn the distributor body in the opposite direction (clockwise) until you obtain the highest rpm without the making the engine begin to run rough.

Tighten the distributor clamp at this position, which is the proper timing position. While you are doing this, avoid touching the coil or coil wires, or you could give yourself a slight shock.

Now that your annual tune-up is complete, your engine should be running at its peak performance level once more. However, there are two other ignition system components that aren’t involved in the tune-up, but might also cause problems.

Ignition switch: This is the switch where you insert the ignition key. It completes a circuit between the boat’s battery and the ignition system’s low-voltage sector.

Its function is simple: it turns things on. However, if its contacts corrode, or if the wires attached to it loosen, the switch will generate all kinds of ignition problems. An old corroded switch can cause hard starting, misfiring, stalling and numerous similar troubles, generally blamed on a more exotic component.

The wiring in the ignition key circuit is often neglected, because it doesn’t seem to be as critical as wires delivering high voltage to the spark plugs. However, if the battery wires are neglected and not cleaned, ignition performance will suffer, and the spark may quit when one of these little wires frays or breaks.

Ignition ballast resistor: This component may be wired in the conductor between the ignition switch and the coil, on 50 hp and larger engines. It prevents the coil from drawing excessive current.

When cold, the ballast resistance is lower than when it is hot. This allows the ignition coil more power for starting when cold; then it drops the amps for proper running characteristics as the current flow warms the resistor.

In the damp marine environment, these resistors often corrode. When that happens, either spark intensity will be reduced (causing the engine to be sluggish), or else the ignition will be killed entirely. In that case, even if the engine is perfectly tuned, it will not start.

If you’re tuning up or rebuilding an Atomic Four engine, the following suppliers may prove invaluable:

Moyer Marine Inc., 3000 Derry St., Harrisburg, PA 17111; (717) 564-5748; www.moyermarine.com. Specializes in Atomic Four repair and rebuilding; publishes an Atomic Four newsletter. Offers a service and overhaul manual and a parts list.

Featherman Enterprises, 90 Walnut Drive Wellesville, PA 17365; (717) 432-0601. Handles parts and rebuilt Atomic Four engines for Moyer Marine.

Indigo Electronics; (800) 428-8569. Offers aftermarket upgrades, including an electronic ignition system kit, a freshwater cooling kit, a crankcase ventilation kit, an oil filtration kit, electronic fuel pumps, high-output alternators and specially designed Atomic Four propellers (10 by 7.4 inch three-blade stainless steel props).

Cruising Designs; (978) 922-2322. Offers a 12 by 7 inch two-blade polymer propellers for Atomic Fours, for improved forward and reverse thrust.