Dick, 2003 U320 40′
Glow plug Troubleshooting, 2003 U320 Power Tech 10 KW Generator Kubota engine. Each glow plug draws about 9 amps so altogether they draw about 40 amps.
To check them clamp meter over the wire that is connected to all of them and initiate start sequence.
Should get 40 amps or so which will decrease as the plugs heat up.
Notes:
1. In cold weather, the engine may fail to start and indicate a fault inside.
2. Go outside, turn Off the Main breaker and then turn it back on. This resets it.
3. Attempt to start again from outside. Repeated attempts from inside will cause a different error.
4. It could take a few attempts.
5. If there are one or more bad glow plugs the problem is worse, but should still start. It’s just time to check them.
6. Fuel level below1/4 tank will cause it not to start.
7. Today the price for a glow plug at FT is $57.63.
Source: Alton at Foretravel 4/19/12
Here is a related quote from Pierce Stewart that should help isolate bad glow plugs that might need to be replaced.
“There are 4 glow plugs (if you have the 4 cylinder engine). They are located right below the intake manifold. Using a 12V test light, connect the clip to the ground and push the sharp end onto the nut at the end of any of the glow plugs. It should light when you preheat the plugs. If no light, check relay “G”. To check each plug separately, unscrew the nut at the end of each plug and remove the wires. Connect the clip to 12V positive and go to each plug with the probe. The light should come on if they are good. No light indicates an open circuit (they are bad). If one is bad, it will cause hard starting or in cold weather, it may not start at all.”