BASIC ENGINE MATTERS
Important Note: At all times, regardless of frequency of operation, it is not good practice to run the engine for only a short period of time. It should be operated 30 minutes at a very minimum to reach normal operating temperature.
It is also good practice to occasionally run the engine at full load for a period of time (a minimum of 5 minutes) to keep the engine clean of moisture and carbon accumulations from short run periods or long idle periods.
The engine will be in alignment with the propeller shaft when the faces of the two engine coupling halves are parallel within .003 of an inch or less. A feeler gauge is used, checking all around the two coupling faces and shims added under the engine mounts, until the two faces are in alignment. Shims may be fabricated from pieces of .005 to .010 sheet metal.
If no feeler gauge is available, four narrow strips of paper can be placed between the coupling faces at four points around the circumference. Any variation of alignment can be determined by the looseness of any one of the strips. Each time a shim is added or removed, tighten all holddown bolts and recheck alignment.
Extra care at this time will pay off in terms of future performance.
Do not attempt to bring the two faces of the coupling together by springing the propeller shaft. When the engine is in perfect alignment, bolt the two halves of the coupling together. With the engine in neutral the propeller shaft should turn easily. If it does not, check for tightness in the stuffing box or slight mis-alignment in strut location or angle. (Plate 12)
Proper Oil Level in Atomic Four Engines
There has been sane confusion regarding the proper oil level for Universal Atomic Four Engines in Tritons. The proper level is indicated on a brass plate secured on top of the reverse gear cover. This must be viewed through the 6" cockpit access plate, using a flashlight. My engine (1961) indicates that the second mark on the dipstick is proper for the installed engine angle. This requires approximately 2 1/2 quarts of oil. Using this level, my engine has given perfect operation for 12 years. I have an engine hour meter and change oil every 50 engine hours. (Approximately one season's operation.) Due to possible changes in dipstick design or markings on the brass plate, I recommend each owner inspect his engine and instruction book to determine proper oil level.
Engine Sump Pump
Universal Atomic Four engines installed in Tritons are fitted with a hand sump pump located below and slightly aft of the carburetor. This pump is used to remove old oil from the engine crankcase prior to filling with fresh oil. After 8-12 years use, the punp may fail to operate due to deterioration of the leather cup sucker. When this occurs, the pump must be removed to install a new sucker. To remove the pump, the carburetor and fuel pump must first be removed. This is a somewhat tricky and tedious job requiring end wrenches, a ratchet socket wrench with extensions, and patience.
Engine life will be greatly with frequent oil draining. Twice a year is not too often for Atomic Four engines used year around as we do on the West coast. Once in the spring and once in fall should do it. A pint of Rislone concentrate additive, or equal, will help inhibit sticking valves, too.
An easy way to collect the oil being drained is to attach a rubber hose at the hand pump with its free end stuck into an empty plastic Clorox bottle, one gallon size. Throw the used oil and bottle away when the crankcase has been pumped empty. Always get the engine warm before draining.
Installing New Water Pumps Part No. 295625
The water pump drive shaft is piloted in the accessory drive gear with a slot in the shaft fitting over the pin in the drive gear hub. There is clearance between the shaft and the outside diameter of the hole into which the shaft pilots. When installing a new pump, tighten the mounting screws finger tight, then start up the engine and run at idle speed for 2 to 3 minutes to allow the pump drive shaft to center up around the drive pin. After the pump has found its normal center, tighten the pump securely in position, and this will eliminate the possibility of any excessive pump shaft wear.
Carburetor Care and Servicing
Some problems have been experienced with carburetor operation and performance especially in salt water areas.
Corrosion takes place, especially during storage periods, and since the carburetor is quite small, some of the openings in the jets and channels tend to become plugged. This is especially true of the idle fuel channel. Accumulations of foreign particles in the fuel, plus corrosion, tend to gather and plug the small opening at the bottom end of the channel. This opening is generally missed by mechanics when the carburetor is cleaned.
The engine will not operate properly at engine speeds below 800 RPM unless the idle channel is open. To clean this idle channel proceed as follows:
1. Remove upper carburetor body.
2. Remove main jet adjustment.
3. Remove main jet.
4. Remove main discharge jet.
5. Clean out idle fuel pick up passage using a 1/32" drill or small stiff wire. Wash carefully after cleaning to remove all foreign particles.
6. Re-assemble and mount on engine.
While you have the carburetor apart, it may be a good idea to check the condition of the fuel shut-off valve needle. if this needle shows any signs of a groove forming, it should be replaced to prevent fuel leakage through the carburetor.
The correct float setting is also very important. If carburetor adjustments have been altered, start with a standard setting which is:
1. Throttle stop screw 1 1/2 turns to right from fully closed position of throttle plate.
2. Idle needle valve one turn open (to left) from seat. Adjust gradually to right or left until engine runs steady at idling speed.
3. Main jet adjustment 2 1/2 turns open (to left) from seat. Turn adjustment in (to right) until engine speed is noticeably reduced. Gradually turn to left (out) until engine runs smoothly and as fast as this throttle position will permit. Too rich a mixture will cause fouled spark plugs and carbon deposits.
Parts Numbers for late model engines
Most recent engines used Delco distributors. Older "Auto-Lite" distributors have caps held on with two external spring metal clips. Delco units on the Atomic Four use caps retained with two screws. Here are part numbers for these units:
"Standard Ignition Part Numbers" (prefix "DR" stands for Delco-Remy) Cap DR-437
Rotor DR - 314
This distributor is used in Chevrolet "Vega" cars, prior to electronic ignition and should be readily available.
Wet Spark Plugs
Sometimes during heavy weather sailing, water will be taken in through the exhaust outlet when the boat is heeling far over or knocked down. This water then finds its way into one or more cylinders via open exhaust valves. More often than not, the engine can't be started afterwards.
Some skippers have installed shut-off valves in the exhaust pipe and water outlet from the muffler. One Triton owner we know has a cork on a line attached to the backstay. He puts the cork in the exhaust outlet on rough weather days. The only trouble with these ideas is that you have to remember to turn off the valves, or to put the "potato" in the pipe.
Having a marine engine shop get the engine started again seems to be a fairly expensive job. Really, it's not that hard. All you need is a dry set of cleaned spark plugs.
If it happens to you, remove the wet plugs and crank the engine over with the starter several times. You will see water vapor coming from the empty spark plug holes. When vapor no longer comes forth, install a dry set of spark plugs and start the engine up. Take the wet set of plugs to a service station and have them cleaned. Carefully wrap each plug in Saran Wrap plastic paper and store on the boat for the next occasion.