The Northern Lights LP668D is a 6.8 L 6-cylinder natural engine rated at 2200 rpm. It powers generator sets from Northern Lights. It holds 19 L (5.0 gal) of oil.
Also known as: Alaska Diesel Electric LP668D
Part of the Northern Lights LP668D engine family — 2 variants share parts & fitment.
| Oil capacity | 19.0 L |
|---|---|
| Displacement | 6.8 L |
| Cylinders | 6 |
| Aspiration | Natural |
| Rated speed | 2200 rpm |
How to read your Northern Lights engine serial & model number →
| Symptom | Cause | Remedy |
|---|---|---|
| Engine failures | Failures often occur in remote areas far from competent assistance. | |
| Battery charging regulator could be ruined | Switch is turned OFF while the engine is running | |
| Engine fails to start on first attempt | Do not crank the starter for more than 15 seconds consecutively. Ensure the starter has stopped completely before re-engaging. | |
| Engine temperature rises over 200°F (94°C) | Shut down the engine and investigate the cause of overheating. | |
| Shutdown is activated and temperature gauge shows within normal range | Check the engine crankcase oil level. If 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 after a few seconds of operation. If the oil level is normal, DO NOT restart the engine. Call your Northern Lights or Lugger dealer for assistance. | |
| Engine temperature rises above 205°F (97°C) | Shut off the engine immediately. |
Fault codes and symptom→remedy steps extracted from this engine’s service/owner documentation; verify against the official manual before servicing.
Compiled from service & troubleshooting documentation across every generator set that uses the Northern Lights LP668D.
The Northern Lights LP668D engine has an oil capacity of 19.0 liters.
The Northern Lights LP668D has a displacement of 6.8 liters with 6 cylinders.
The Northern Lights LP668D powers 1 generator set(s), including Northern Lights LP668D.
A commonly reported issue on generators using the Northern Lights LP668D is: Shutdown is activated and temperature gauge shows within normal range. Fix: Check the engine crankcase oil level. If 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 after a few seconds of operation. If the oil level is normal, DO NOT restart the engine. Call your Northern Lights or Lugger dealer for assistance..