Northern Lights Lugger M843NW3, Operator'S Manual

OM843NW3 5/21

14

SHUTDOWNS AND ALARMS

1.  Your unit is fitted with a system to protect it from high 

water temperature or low oil pressure.

  a.  Generator sets have shutdown systems to stop the 

    engine. They have no warning horns.

  b.  Other alarms and shutdowns are available as 

    optional equipment.

NOTE:  Do not rely on your warning to the 

  exclusion of careful gauge monitoring. Watching 

your gauges can prevent damage to the unit and 

dangerous power losses.

2.  Do the following when your warning or shutdown 

system is activated:

  a.  Engage the preheat switch to check the 

    temperature gauge.

  b.  If above 205°F (96°C), use the Troubleshooting  

  Guide on page 25 to isolate the cause of  the 

   overheat.

Do not open the filler cap when the engine is 

warm.  Opening a warm filler cap can cause 

severe burns.

  c.  Make repairs. Restart your Marine set after the 

    temperature gauge registers below 200°F (94°C).

  d.  Watch the temperature gauge regularly and 

    turn off the unit if the temperature rises above  

    205°F (96°C) on Marine units. Repeat 

   troubleshooting.

3.  If shutdown is activated and the temperature gauge 

shows temperature within normal temperature range:

  a.  This shutdown could have happened because of a  

  too high exhaust temperature.  This could have  

  been caused by a damaged impeller or a partially  

  blocked sea water strainer.  Check the sea water  

  strainer first.  If it is clear, then check the 

    condition of the sea water pump impeller.

  b.  Check the engine crankcase oil level.

  c.  If the oil level is low, fill with recommended 

    lubricating oil and restart. Watch the oil pressure 

    gauge carefully and shut off the engine if it does 

    not show a normal reading (20-60 PSI) after a 

    few seconds of operation.

  d.  If the oil level is normal, DO NOT restart the 

    engine. Call your dealer for assistance.

SPARE PARTS

1.  Northern Lights recommends that you keep the 

following spare parts on hand for field service. The 

parts are available from your local Northern Lights 

dealer. Marine models have optional “On-Board-

Kits,” a handy box that contains the most common 

parts you will need.

2.  Northern Lights standard spare parts kit (P/N 

38-0120)*

 contains:

  a.  Primary and secondary fuel filter elements

  b.  Oil filters

  c.  Air filter element

  d.  Drive belt

  e.  Thermostat and gaskets

 f. 

Raw water pump impeller with gaskets 

  g.  Water pump cover o-ring

  h.  Rocker arm cover gasket 

3.  Intended for long-distance cruisers, Northern Lights 

world class spare parts kit (P/N 38-03126)* contains: 

  a.  Primary and secondary fuel filter elements

  b.  Oil filters

  c.  Air filter element

  d.  Drive belt

  e.  Thermostat and gaskets

 f. 

Raw water pump impeller with gaskets 

  g.  Water pump cover o-ring

  h.  Rocker arm cover gasket 

  i.  Impeller kit with gasket

  j.   Injector assembly

  k.  12v glow plug

  l.  Gasket set

  m.  Fuel lift pump and mtg. gasket

   n.  O-ring

  o.  Relay, SPDT 12v 50A

  p.  Workshop manual  

Operating Procedures

Updated 10-3-19

!

DANGER

*- For use with M843NW3 and M843NW3G generator sets with heat 

exchangers.  Consult your Northern Lights dealer for your unit’s 

specific spare parts requirements.