Northern Lights L944T Engine

Tools: Feeler gauge, Wrenches

1. Readjust valve clearance after first 50 hours; check every 500 hours thereafter.
2. Check the valves when the engine is cold.
3. Rotate crankshaft clockwise to bring each piston to top dead center on the compression stroke; notch on pulley aligns with pointer and No. 1 cylinder valves rock.
4. Measure each valve clearance with a feeler gauge in firing order 1-3-4-2.
5. Loosen lock nut on adjustment screw, insert feeler gauge, adjust until it slides with slight drag, tighten lock nut and recheck.
6. Adjust remaining valves and replace the rocker arm cover.

⚠ Do not run the engine with the air cleaner removed.

⚠ Do not clean the filter with diesel fuel, solvent, or gasoline.

1. Visually inspect air cleaner every 250 hours.
2. Take off the hose clamp on the bracket and the hump hose to detach the air cleaner.
3. Make sure the hump hose is clean inside and the new element is clean and installed properly.

⚠ Battery gas can explode; keep flames and sparks away.

Tools: Hydrometer

1. Check electrolyte level every 50 hours, or once a month; add distilled water to manufacturer's recommended level.
2. Check and clean batteries, cables and terminals every 100 hours using water and baking soda solution.
3. Flush with clean water, tighten terminals and grease them.
4. Check battery condition with a hydrometer every 500 hours.

⚠ Escaping diesel fuel under pressure can penetrate skin causing serious personal injury; relieve pressure before disconnecting lines.

⚠ Use a piece of cardboard or wood, not hands, to search for suspected leaks.

1. Loosen air vent plug on the fuel filter about 1-1/2 turns, covering the vent with a cloth.
2. Unlatch priming pump cap on fuel feed pump; move priming pump plunger up and down.
3. Close air vent plug when no more air bubbles are seen in fuel flowing from the vent.
4. To bleed at the injection pump, loosen its air vent plug about 1-1/2 turns and pump the feed pump.
5. When no bubbles remain, push down priming pump cap and turn clockwise to lock it.
6. If engine still will not start, loosen a fuel line at the injector and crank until pure fuel escapes, then tighten.

1. First 100 hours are critical to engine life and performance.
2. Constantly check engine temperature and oil pressure gauges.
3. Oil consumption is greater during break-in as piston rings seat.
4. Change engine oil and filter at 50 hours, then again at 100 hours.
5. Maintain at least 75% load for the first 100 hours; no less than 50%; vary the load.

⚠ Overtightening can damage the filter housing.

Tools: Filter wrench

1. Use a filter wrench to remove old filter and dispose of it in an approved manner.
2. Make sure old filter gasket is removed and discarded; clean mount face.
3. Spread a thin film of engine oil on the new filter gasket and screw it on until gasket meets sealing surface.
4. Tighten by hand only, one-half turn farther; do not use a wrench.
5. Fill engine with recommended oil, start and check for leakage; stop, wait 3 minutes, check oil level.

1. With engine stopped, check oil level in crankcase daily.
2. Oil level must be between the high and low marks on the dipstick.
3. Fill with recommended oil only to the high mark on the dipstick.

⚠ Be sure to close the sea-cock before working on the cooling system and reopen it after.

1. Flush cooling system every 2000 hours or every 12 months, whichever comes first.
2. Remove fill cap and open drains on engine block.
3. Pour clean water into engine until water coming from engine is clear of discoloration.
4. Close drains and refill with recommended coolant mixture.
5. Check hoses and connections and repair any leakage.
6. Start engine, run five minutes, shut down, let cool, and check coolant level.

⚠ Scaling removal with 50/50 muriatic acid and water must be performed only by a qualified technician with the heat exchanger removed.

Tools: Metal rod

1. Clean the heat exchanger core as needed.
2. Drain the expansion tank and heat exchanger.
3. Remove the heat exchanger end covers.
4. Clean inside the exchanger core tubes using a metal rod; flush, inspect, and clean again if necessary.
5. Reassemble the heat exchanger, fill the cooling system, start engine and check for leaks.

⚠ Change oil when engine is warm but not hot.

⚠ Dispose of waste oil in an approved manner; never use flushing oil.

1. Change engine oil and oil filter after 50 hours; use diesel-rated break-in oil during first 100 hours.
2. Change oil and filter again at 100 hours, then every 250 hours.
3. In intermittent cold weather, change oil every 1000 hours or six weeks, whichever comes first.
4. Change oil at any seasonal temperature change requiring a new viscosity.
5. Loosen clamp on oil change tube, remove cap, drain oil, replace cap and tube.
6. Refill engine with recommended oil.

⚠ Place protection under the screwdrivers so the pump housing is not damaged.

⚠ Keep an extra impeller and cover gasket in reserve on board.

Tools: Needle-nose pliers or two screwdrivers

1. Change the raw water pump impeller every 500 hours, or as needed.
2. Remove the pump cover and pry out the impeller using needle-nose pliers or two screwdrivers.
3. Be sure to remove all pieces of a failed impeller.
4. Clean the inside of the housing.
5. Press in the new impeller and place the sealing plug in the outer end of the impeller center.

1. Check tension and wear on the V-belt after 50 hours.
2. Press on the belt at the midpoint between the crankshaft and alternator pulleys.
3. Tension is correct if belt can be depressed about 10-12 mm with 10 kg (22 lbs.) force.