Northern Lights Genny

[Bob Bradley]

I finally got around to doing a service on the genny in my new boat. It's a NL with a Luggar engine. Basic maintenance, including oil change, fuel filters, air filter cleaning, impeller, and antifreeze change. It did smoke a bit more than my old genny and I found the air filter foam dirty and cleaned it.

It wouldn't start at first after the fuel filters were done so I went through the steps to bleed the system. When it still wouldn't start I began to crack the fuel lines to bleed them. As I tried to loosen the first one, the injector turned instead of the line fitting. That caused the return line to crack and begin to leak.

Great. Never do maintenance. Something always breaks. So, I've ordered a new return line and will be installing it this week. So, my question is this... Since I already have 3 brand new injectors in my maint kit, should I just go ahead and replace them too since everything that needs to be removed to do so will already be off? The engine has about 4k hours on it.

Oh, and it didn't need to be bled in the first place. Turns out I forgot to open the thru Hull after replacing the impeller and the lack of water flow was detected by a sensor.

 

[Pascal]

I used to run a boat with a pair of luggar powered 20KW NLs. They were pretty much self bleeding. It was a few years back but I don’t even recall a priming pump. The lift pump was electric and you d just hold the run button to run the pump for a while to bleed the circuit

Very reliable

 

[Avenger]

Gee, too bad you don't know of a fuel injection shop that could test those injectors for you.

 

[Bob Bradley]

Don't worry, if I swap them you'll be getting them.

 

[Captain Ralph]

How old or reliable do you think you spare injectors are? Fresh or recent pops on them?
IMO, Injectors that spend more than a week on a shelf, are suspect.

Nice to have for emergencies when you know you have a bad one on your engine. Your spares give you 3 chances to replace one bad injector.
But when your engine is running fine and then install stored injectors, you may be inserting problems.

While your are looking for DIY adventures, adjust the valves.

 

[Pascal]

At the risk of jinxing myself I don’t think I ve ever had issues with injectors.

My 20 year old 3000 hours Isuzu powered Norpro 18 has its original injectors. The NL 20s I mentioned had 9000 hours and where 13 years old when the boat sold. Original injectors afaik. I put 4/5k on each and never touch the injectors. We had to replace an injection pump on one of them but GT hat was it.

Same on mains… I ve put like 4000 hours on 3412s, 2500 on C32s. Never had to get an injector replaced.

 

[Bob Bradley]

Yea, that's why I'm concerned. But since the can of worms is already open, welllll ...

 

[carolinacoast]

There are many current or former aircraft owners on this board. After upgrading to my best mechanic over 15 years, 2 states away, his opinion was always to avoid maintenance induced failure from a repair, UNLESS the risk of the repair was warranted by great data, or significant calendar risk that warranted the risk(Part 91, obviously). Boat engines are usually less risky to human life. IMHO, the injectors should stay in their boxes, until needed.

 

[brettportzer]

Not being an aircraft owner, I have always thought that the name of the game with aircraft maintenance was to perform it on a schedule, such that things never really break in use?

Whereas, with boats, it seems like no one wants to touch anything until it breaks?

There are many current or former aircraft owners on this board. After upgrading to my best mechanic over 15 years, 2 states away, his opinion was always to avoid maintenance induced failure from a repair, UNLESS the risk of the repair was warranted by great data, or significant calendar risk that warranted the risk(Part 91, obviously). Boat engines are usually less risky to human life. IMHO, the injectors should stay in their boxes, until needed.

 

[Avenger]

Don't worry, if I swap them you'll be getting them.

If we test them, you'll know whether you need to swap them or not. No charge for pop-testing. Just saying.

 

[Captain Ralph]

Not being an aircraft owner, I have always thought that the name of the game with aircraft maintenance was to perform it on a schedule, such that things never really break in use?

Whereas, with boats, it seems like no one wants to touch anything until it breaks?

Air planes are inspected and tested very well. There are items that do require service on cycles or hours schedules. But nothing is worked on out of its service schedule unless it fails before its time. That out of routine failed part is analyzed very well as to why it failed.
Inspections may also find loose hardware, chafe on wire bundles and hoses. These are inspected in depth and fixed quickly and completely.

On a boat, there are inspections and service schedules. Not as tight as an aircraft but still important. We look for loose hoses, wires, rusted hose clamps, battery levels, bilge levels and change oil and filters on a schedule.
When a boat part fails, not to much failure analysis is given. Often it was from lack of inspection, ie; Bilge pump wire crimp turned green.

Very similar to air craft, we do not replace perfectly working engine starters but we inspect the cables and wires that attache to it.

Maybe some of our failures are because of, out of routine schedules;;
a 12000 hour gen-set has loud ticking sounds from the valve cover. Is that because something just broke or it was not rebuilt at 10000 hours. Or, the valves were not adjusted every 2000 hours.

OTOH, I remember reading in some owners manuals to remove and clean injectors at some high hour mark. These manuals do not say replace good injectors.

So, when you are in your ER, feel like a Aqua-Space Craft inspector and look over things well.