Kohler L600 Engine

Tools: #43 drill (.089)

1. Carburetor unit: loosen three screws on outside cover plate, shift cover clockwise for richer or counterclockwise for leaner, then tighten.
2. Manifold type: remove air cleaner to observe choke plate; adjustment must be made on a cold engine.
3. Move choke arm until hole in brass shaft lines up with slot in bearings.
4. Insert #43 drill (.089) and push all the way down to engage notch in base of choke unit.
5. Loosen clamp bolt on choke lever and push arm upward to move choke plate toward closed position.
6. Tighten clamp bolt after desired position is attained, then remove drill.

⚠ Do not force the needle - damage to needle or seat will result.

1. Stop engine and turn Main Fuel adjustment in (clockwise) until needle bottoms lightly.
2. Back out for preliminary setting: 2-1/2 turns on side draft or 1-1/2 turns on up draft.
3. Start engine and warm to normal operating temperature, placing engine under normal load.
4. Move Main Fuel needle in until engine slows from lean, then out until speed again drops from overrich.
5. Set needle about halfway between lean and overrich settings.

1. Turn idle stop screw in about 2 turns or until butterfly valve is held slightly open.
2. Turn IDLE FUEL screw (gas carburetor only) all the way in until it bottoms lightly.
3. Turn MAIN FUEL or LOAD screw all the way closed then back out 5 turns for initial setting.
4. Start engine and adjust MAIN FUEL until engine runs smoothest at governed speed no load.
5. Put engine under normal load and readjust as needed for final power adjustment.

⚠ If one governor setting is readjusted, the other should also be readjusted.

Tools: Hand tachometer or frequency meter

1. With plant running at full load governed speed, check speed with hand tachometer or frequency meter.
2. Speed range: loosen locking nut on speed adjusting screw, turn screw clockwise to increase speed/frequency or counterclockwise to decrease, then lock nut.
3. Sensitivity (droop): to make control more sensitive, loosen nut at bottom of adjusting eye bolt and tighten top nut drawing eye bolt head closer to governor arm pivot point.
4. To make control less sensitive, loosen top nut and tighten bottom nut to move eye bolt head away from pivot point.
5. Tighten the previously loosened nut to lock the eye bolt, then recheck speed since sensitivity adjustment affects speed.

⚠ Do not connect a battery to the magneto as this will ruin the coil windings.

Tools: Timing light

1. After confirming breaker point gap is set, connect timing light to #1 cylinder and start engine.
2. Aim timing light into pointer area on bell housing; SPK mark should be even with pointer as light flashes.
3. If not, loosen (do not remove) the two magneto mounting capscrews.
4. Shift position of magneto (top flange eccentric) until SPK mark is exactly centered.
5. Retighten mounting capscrews.

⚠ Do not permit inlet pressure to exceed maximum (usually 6 oz.).

Tools: Manometer or ounce pressure gauge for inlet pressure check

1. With engine stopped, slowly turn lock off screw out (counterclockwise) until fuel starts to flow through the regulator.
2. Turn screw in (clockwise) until flow stops and note position.
3. Turn screw in one more turn for final setting.

⚠ Do not connect a battery to the magneto - this will ruin the coil windings.

Tools: Timing light

1. Rotate engine by hand until timing mark on generator fan (SPK) lines up with timing mark on generator housing and compression is felt in #1 cylinder.
2. Connect lead to magneto terminal #1, hold end about 1/8 inch from case, turn magneto gear clockwise through each impulse release until spark is observed.
3. Turn gear backwards counterclockwise until notch in gear and hub lines up with yellow timing mark on magneto flange.
4. Hold #1 timing position of both engine and magneto while installing magneto; connect leads per illustration and ground strap to controller terminal #5.
5. Install radio shielded plugs and use a timing light for precision timing.

Tools: Timing light

1. Turn engine until SPK mark on flywheel-generator fan lines up with timing line and pointer on bell housing; check #1 cylinder at top of compression stroke.
2. On magnetos with timing window, turn magneto gear counterclockwise until white mark lines up with indicator and hold.
3. Position gasket and guide magneto gear into engagement with idler gear, keeping timing mark centered, then secure magneto.
4. Reconnect high tension leads and check ignition timing with a timing light.

Tools: Feeler gauge

1. Remove spark plugs then turn engine until #1 piston is at Top Dead Center on compression stroke - both valves closed.
2. Insert feeler gauge between tappet and end of exhaust valve.
3. Adjust clearance by moving tappet setscrew so a very slight drag is felt on the feeler gauge as it is withdrawn.
4. Repeat procedure on the intake valve of #1 cylinder.
5. Turn engine until the next piston is at TDC compression and repeat on each cylinder in turn.

Tools: Compression gauge

1. Be sure air cleaner is clean and exhaust is not restricted before checking compression.
2. Insert gauge in spark plug hole and take several readings on each cylinder.
3. Consistent readings in the 110 to 120 psi range indicate good compression.
4. Reconditioning is indicated if readings fall below 100 psi or if readings between cylinders are far apart.

1. Adjust belt so it can be depressed about 1/2 to 1 inch in center of the longest span between pulleys.
2. L600 with adjustable pulley: loosen nuts on pulley hub and move hub in closer to increase tension or away to decrease tension; retighten nuts.
3. To replace belt on L600, remove belt guard and loosen pulley hub until belt can be slipped off the pulleys.
4. L654 radiator models: loosen the two mounting capscrews and shift plate out to increase tension or in to decrease tension; move plate all the way in to remove a bad belt; retighten capscrews.
5. Marine models: remove belt guard, loosen adjusting plate capscrews, shift plate for proper tension, retighten and replace belt guard.

Tools: Timing light, Feeler gauge

1. After each 500 hours remove distributor cap and check breaker points; clean with lacquer thinner and lint free cloth.
2. Replace points if badly worn or pitted; set point gap at .020 inch at maximum opening.
3. Every 500 hours remove the plug on the distributor housing and the plug on the drive housing and fill reservoirs with SAE 20 weight oil, then reinstall plugs.
4. To retime: rotate engine until SPK timing mark lines up and compression is felt in #1 cylinder.
5. With distributor removed, remove cap, rotor and cover, reinstall rotor and rotate drive gear until ignition points just begin to open with rotor positioned to fire #1 plug.
6. Install distributor, reassemble cover, rotor and cap, connect spark plug leads and use a timing light for precision timing.