Lifetime of Cummins (Bosch) fuel injectors?

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DDW

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In a QSB, but probably all the HP common rail engines are similar. The Dodge truck people seem to think that 100,000 miles or so is time to replace. That is around 2000 hours. I've had a couple of other (boat) owners state that they replace them somewhere around there and feel that it makes the engine run a bit better. Bought new from Cummins they are very expensive, but reconditioned somewhat less so.

My engine seems to run well enough, no hard starting, idles well, but does seem to have the occasional miss at cruising rpm. This has not changed from when I bought the boat at 1000 hours engine time until now at 2500. I guess a $300 session with the Cummins computer might tell if this is really happening or just my imagination.

How ofter are you owners with a QSB or QSC changing injectors?
 
Your are probably due. I did mine at 25000hrs on my cta's used remanufactured units and kept the old ones for emergency spares. It cleaned up a rough idle.
 
Did mine at 2250 on my 6CTA. BTW Cummins just announced 20% off injectors today until the end of the year on shop.cummins.com
 
Your are probably due. I did mine at 25000hrs on my cta's used remanufactured units and kept the old ones for emergency spares. It cleaned up a rough idle.
25000? or 2500?

I'd probably do the same, buy rebuilt and eat the core charge, keeping the old ones on board. If all my cruising was weekends in civilization I might wait until I had a complaint, but the places we go a Cummins shop can be many days (or weeks) away.
 
25000? or 2500?

I'd probably do the same, buy rebuilt and eat the core charge, keeping the old ones on board. If all my cruising was weekends in civilization I might wait until I had a complaint, but the places we go a Cummins shop can be many days (or weeks) away.
Assuming you are in the San Francisco area, there may be an injector service
shop not too far away. Having your own injectors tested and redone as necessary
is the way I would go. Often only a few parts need replacing, saving you money.
Diamond Diesel in Oakland is fairly close and there are several others in your area.
 
We went with Midland Diesel Service in Fargo. They informed me that Cummins had a service bulletin on my injectors such that rebuilding wouldn't be optimal. New injectors with the improved design were $250 from Cummins but $160 each from them. Hence I bought new.
 
$250 injectors must be for the 6BTA. For the QSB, Cummins price is around $950 from Cummins (each). So not pocket change.
 
If you run clean fuel, usually the tips go bad. And that's is usually from buildups on the tips that change the spray pattern. The right fuel conditioner will clean and keep the tips clean. Then the tips will last until the spray holes enlarge or the needles wear out. And clean fuel prolongs their life. I have Detroits with injectors with more internal parts. So running dirty fuel greatly shortens their life. I run 2 micron fuel filters and keep my tanks clean.
 
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