Injector inspection??

[wmiii]

We are fixin' (Tennessee talk for "getting ready") to go to the Bahamas and after checking my Yanmar owners manual, I notice that I should check my injectors every 600-1000 hrs. With over 1500 hrs on my engine, I've never had them checked.
How important is it that I get this done? What do I need to do for this project?

Thanks,
Wm Mayberry
OPTIMYSTIQUE
IP 37-30

[erps]

That's CYA talk from the manufacturer to pop them out and send them to an injector shop to check spray pattern and to see if they're leaking (either will cause some inefficient running or starting problems). From my perspective with some time as a diesel mechanic, I practice the "if it ain't broke, don't fix it" approach. If you keep up on your fuel filters and oil changes your engine is barely broken in.

[Goodnewsboy]

Take them out and send them to a competent diesel fuel injection service shop. They will check for delivery pressure and spray pattern. If they don't check out you can have them rebuilt or buy new. Although your engine doesn't have a lot of hours, it is probably good to follow the OEM recommendations before your trip.

I'd carry at least one spare injector, a set of copper washers (gaskets) along with other recommended engine spares.

[camaraderie]

Ditto on the spares but unless yer seeing something out the back of the boat that ain't right...I wouldn't mess with them. No problem getting competent diesel help in the Abacos or Exumas should you need some there. Have a great trip!

[wmiii]

about removing the injectors?
I'm away from the boat now so I can't look. I've never removed them.
And once removed and checked, is there anything I need to know about replacing them?

[RichH]

Be sure to use NEW banjo gaskets on any fuel line connection you disturb. Be sure to use a torque wrench on the injector hold down brackets, etc.

[Goodnewsboy]

Pay close attention to advice from RichH. Those injector holders are easy to bend or break if you over-torque the fasteners. I learned that the hard way.

[wmiii]

Looks like I need to get a tourqe wrench. I check it outy when I get back down to Florida.

Wm

[sailaway21]

FYI-the best way to never have to deal with the injectors is to supply good clean fuel to them. That involves where you buy your fuel and how you filter it on board.
Carrying the spare injector is a good idea, it saves ordering one when time may be a factor. You're not going to be changing these out at sea unless something is really, really wrong. The norm, when the engine has a miss, is to pull the injectors and take them to a mechanic. He has a hp pump that he attaches to each one and can observe spray pattern. The same pump is capable of pumping cleaning solvent through the injector. If he cannot clean the injector up adequately to provide an atomized spray pattern, it must be replaced. The problem with bad injectors is that, instead of atomizing fuel, they spray liquid fuel, usually at one angle, right on to the cylinder wall effectively washing away all of the cylinders lubrication. The damage done to the engine is not so much from mis-firing as the degradation of lubrication on the cylinder wall.
Twenty-five years ago engine builders were well on their way toward standardizing injectors across engines and injectors were $20-30 a piece. Today, every engine has it's own specific injector, and $100 a piece is considered reasonable. Go figure.