Continental Red Seal Y91-273 or Y91-264 Engine

⚠ A change in the BTU rating of the fuel used will probably necessitate readjusting the valve.

1. With full load on the plant, turn the knurled head gas adjustment valve in (clockwise) until voltage drops noticeably or the engine begins to lose speed.
2. Turn the screw slowly out (counterclockwise) until voltage rises to normal and the engine runs smoothly.
3. Check the operation at various loads.

⚠ Be sure all gaskets are in their proper place when reassembling.

Tools: Screwdriver

1. Keep the carburetor clean and free of sediment; clean jets and passages with compressed air or a fine soft copper wire.
2. Turn the idle adjustment needle out (counterclockwise) until the engine begins to misfire.
3. Turn the needle in (clockwise) until the engine runs smoothly.
4. Adjust the throttle lever stop screw so there is 1/32 in space between the screw end and the throttle stop at no load.

⚠ Too tight a belt will have a short life and cause excessive strain and wear on the water pump bearings.

⚠ A belt too loose will slip, wear out rapidly, and result in inefficient cooling.

Tools: Wrenches

1. Loosen the two lock bolts on the fan pulley.
2. Turn the front half of the pulley clockwise to narrow the pulley groove and tighten the belt.
3. Turn the pulley counterclockwise to widen the groove and lessen belt tension.
4. Allow 3/4 in play in the belt.
5. Tighten the adjustment lock screws securely and check them frequently.

⚠ Any change in the setting of the sensitivity screw will require correcting the speed screw adjustment.

⚠ Be sure all load is removed when adjusting the bumper screw.

Tools: Voltmeter, Tachometer

1. With engine stopped and tension on the governor spring, adjust linkage length so carburetor throttle stop lever clears stop pin by not less than 1/64 in.
2. Start the plant and allow it to reach operating temperature.
3. With no electrical load, adjust speed screw until voltage is approximately 126 volts for a 115 volt AC plant or 121 volts for a DC plant.
4. Apply full load and check voltage; approximately 108 volts for a 115 volt AC plant or 110 volts for a DC plant.
5. Engine speed should be within 1890 r.p.m. at no load to 1745 r.p.m. at full load for an AC plant.
6. If the plant hunts under load, increase slightly the distance between the eye of the sensitivity screw and its support.
7. If hunting occurs at no load, screw the small bumper screw in until the hunt is stopped, but not far enough to increase engine speed.
8. Tighten all lock nuts when adjustments are completed.

⚠ A continuous ping indicates the timing must be retarded.

Tools: Feeler gauge, Hand crank, Wrench

1. Set the distributor contact points to 0.020 in gap at full separation.
2. Remove the flywheel inspection hole cover and turn the engine until the No. 1 piston is coming up on the compression stroke.
3. Slowly crank until the flywheel mark is on center in the inspection hole.
4. Distributor rotor should point to the cap tower for the No. 1 spark plug wire and the points should just separate.
5. If the rotor points to the No. 4 tower, remove the distributor, lift the drive shaft in the cylinder head and turn it one half turn.
6. Start the plant and allow it to reach operating temperature, then test the spark advance by applying full electrical load.
7. Slow the engine by pulling on the governor arm, then release and allow sudden acceleration; one or two pings should be heard.
8. Advance or retard the timing by loosening the distributor clamp and turning the distributor body; retighten the clamp screw.

⚠ Tappets set too close may cause burned or warped valves, seats, and scored tappets or camshaft lobes.

Tools: Three wrenches

1. Remove the valve chamber cover to reach the tappet adjustments.
2. Crank the engine by hand until the intake valve opens and closes; both valves for that cylinder will then be closed.
3. Set the adjusting screw clearance to 0.012 in for both intake and exhaust valves.
4. On engines with Roto type exhaust valves, set the exhaust valve tappet clearance to 0.010 in.
5. Securely tighten the lock nut on each adjusting screw.
6. Make a final check with the engine running at idle speed.

⚠ Do not use an oil heavier than SAE number 20 in a plant being put into service the first time.

⚠ Always use oil of the same brand when adding oil between changes.

1. Fill the crankcase with approximately 3 quarts of good quality heavy duty (detergent) type oil to the high level mark on the bayonet gauge.
2. Fill the air cleaner cup to the indicated level with oil of the same SAE number as the crankcase.
3. Fill the oil cup on the side of the distributor.
4. Place a drop of oil on each of the governor to carburetor link ball joints.
5. Fill the radiator with clean, alkali-free water; the cooling system capacity is approximately 11 quarts.
6. Use only a good grade, clean, fresh, regular automotive type gasoline of 68 to 74 octane rating.

⚠ Be sure that no dirt gets into the bearing.

1. Remove the plate from the housing rear end.
2. Clean all dirt from around the generator bearing cover and remove the cover and gasket.
3. Remove the old lubricant from the bearing with a clean finger.
4. Work about one tablespoon of new ball bearing lubricant into the bearing and again remove the lubricant.
5. Refill the bearing housing about one half full of bearing lubricant, packing it well into the lower half of the bearing.
6. Reinstall the bearing cover, using a new gasket if necessary.

⚠ Do not press the START button continuously.

⚠ Do not overprime.

1. See that the ignition switch is set at the ELEC. START position.
2. For gasoline fuel, press the START button firmly for several seconds to fill the fuel pump and carburetor.
3. Hold the start button in until the plant has reached running speed.
4. If it does not start, press the START button for periods of not more than five seconds at a time with equivalent stops between.
5. If the plant fails to start after a few attempts, check the fuel and ignition systems and repeat.
6. For gas operation, lock the choke control arm down and see that the gasoline supply is turned off.
7. Press the START button; the regulator primer button may have to be pushed the first time. Do not overprime.

⚠ Keep the ignition switch at the ELECT. START position at all times except when actually starting the plant manually.

⚠ While at HAND START, the high water temperature cut-off switch (and low oil pressure switch) is cut out and the plant is not protected against overheating.

Tools: Hand crank

1. For gasoline fuel, use the hand crank to turn the engine enough times to fill the fuel pump and carburetor.
2. Throw the ignition switch to the HAND START position.
3. Crank the engine with a quick upward pull.
4. If equipped with a Sisson automatic choke, have someone pull up on the automatic choke arm while cranking.
5. If equipped with a low oil pressure ignition cut-off switch, hold the momentary toggle switch in contact until the plant reaches running speed.
6. After the plant starts, return the ignition switch to the ELECT. START position.

⚠ The stop circuit will not work if the ignition switch is at the HAND START position.

1. Press the STOP switch momentarily.
2. In an emergency, if the stop circuit fails to work, stop the plant by turning off the fuel supply.

⚠ The carbon seal is fragile and easily broken.

Tools: Puller, Press, Wrenches

1. Remove the nut and lockwasher from the front of the water pump shaft and pull the pulley off the shaft with a suitable puller.
2. Remove the three nuts mounting the shaft support to the body and remove the support assembly.
3. To remove the impeller, remove the set screw and pull or press the impeller from the shaft.
4. To remove the shaft and bearings from the support, remove the set screw from the top of the support and press the assembly out through the front.
5. The seal will be found assembled in the impeller hub; take care as the carbon seal is fragile.
6. To reassemble, reverse the disassembly procedure; make sure the set screw lines up the impeller on the shaft and press the impeller on flush with the end of the shaft.
7. Pack the space between bearings with a good grade of water pump grease.