NL generator issue

[Olly75]

So I have an intermittent issue with my NL genny and was wondering if anyone has any ideas to help.

On a couple of occasions over the last six months I've started the genny as normal but it's not produced any electric power. When I stop and restarted it has worked fine.

This evening I had the same issue so restarted with no luck. I went through the electrical box on the genny, checked all the connections, checked the relays were working and all the fuses and found no issue. So tried starting it under load (the kettle was plugged in ) and it worked fine.

Any ideas on what could be causing the issue?

[GordMay]

Which NL Generator? ➥ https://www.northern-lights.com/technicalinformation/
➥ http://www.northern-lights.com/media...dfs/W673-2.pdf

[psk125]

Sounds like a clutch not engaging sometimes. Relays can stick too, on occasion, so that they seem fine when you test them but don't always work.

[phorvati]

Originally Posted by Olly75

So I have an intermittent issue with my NL genny and was wondering if anyone has any ideas to help.

On a couple of occasions over the last six months I've started the genny as normal but it's not produced any electric power. When I stop and restarted it has worked fine.

This evening I had the same issue so restarted with no luck. I went through the electrical box on the genny, checked all the connections, checked the relays were working and all the fuses and found no issue. So tried starting it under load (the kettle was plugged in ) and it worked fine.

Any ideas on what could be causing the issue?

If you can get it to start after flashing the field(see manual), I would start looking into why the field lost residual magnetism. Dirt related leakage, would be something to ckeck maybe Corroded wires.

[Olly75]

Thank you for the responses so far.

I have a NL M643K generator. I can change out the relays as I have a couple of spares, if the clutch is slipping can I check it myself to find out or do I need to get the unit pulled out?

Having just given myself a crach course on 'flashing the filed' on google, I cant find anything relating to it in any of the manuals I have (parts, workshop, installation), could you give more details?

Many thanks

[a64pilot]

It has a clutch?
I’m pretty sure that’s not likely

[Olly75]

Originally Posted by a64pilot

It has a clutch?
I’m pretty sure that’s not likely

Good news! Thats one thing off the list

[phorvati]

I have the same generator....I was going to upload my copy but it exceeds the limit.
https://www.northern-lights.com/medi..._pdfs/O101.pdf
See pages 20 and 21. I did a lot of work to it, but never had to even look up a clutch. It does have one but its not a clutch in a sense I though of. PO was saying you need to flash the field,etc, but I never really did. I had to do a lot of work on the fuel side (pump/injectors) and heat exchanger and raw water side. But electrical side works very well. I did go over the electrical side just to see what is what. I took terminals off and cleaned them, those fuses were rusty so i wire-brushed the holders and fuse ends, spec-ed out few spares.
That voltage regulator(AVR) is around 900$ or so. That is the big ticket item. Just hope that is still good.

[a64pilot]

Where is the clutch? Between the engine and generator? Clutch or cushion drive?
When cleaning off electrical connections, I’d recommend a light coat of silicone grease, in an auto supply house, they may call it light bulb grease.

[landlockedgm]

Check the brushes to make sure they are not getting short and spring tension is good. Make sure the brush is not stickng in the holder. Check the condition of the slip ring also. Good luck!

[GordMay]

FWIW (couldn't find a shop manual for their smallest genny)
Northern Lights M643K, 4.5kW Generator
Brochure ➥ http://www.devill.net/Documentation/...ights/L572.pdf
Operator’s Manual ➥ https://www.northern-lights.com/medi.../O643-673K.pdf
Operator’s Manual ➥ https://www.northern-lights.com/medi..._pdfs/O101.pdf
Parts Catalogue ➥ https://www.northern-lights.com/medi..._pdfs/P643.pdf

[landlockedgm]

Hi, in the operators manual on pages 20-24 shows the brushes and how to service. I have seen them hang up.Take the round end cover off and you should see them.

[landlockedgm]

Did you get it fixed?

[Olly75]

To resurect this thread..... and apologies for not repsonding back in August, time really does fly!

Changed the bushes (which didnt look unduly worn) but still had the same intermittent issue, until we were two days into our passage to New Zealand when there was nothing being generated no matter what we did. Needless to say my cunning idea to instal an electric hob and remove gas from the boat backfired......

So for the rest of the passage and since there has been no luck and the genny refuses to produce electricity.

Im wondering if it could be the temperature sensor on the exhaust elbow playing up, if the sensor wasnt working would it stop the genny producing?

[skipperpete]

If any of the sensors were activated or failed in the activated mode the engine would simply shut down.
There are a number of tests that can be done to verify or dismiss all the usual suspects ( rotor windings, stator, AVR) but they require a good multimeter and a great caution if doing any of the tests with the engine running, bad things can happen if you touch a live circuit.
Do a few simple static checks first, like check the output of the little AC generator and the rectifier/regulator thats bolted to the engine bracket just below it. You can drop off the belt and spin the alternator by hand and check output on the two blue wires.
Check that the isolating switch on the control box actually functions and follow the AC wiring for its entire trip from genset to main panel... often, installers will do a splice or fit a junction box rather than run a single length cable.
Don't despair if is the AVR, an aftermarket one is about $30 from many of the chinese online guys and they work just fine.