Anyone have injector troubles on Cummins?

[jastarn50]

I just bought my 2008 Tiffin 37QDB Allegro Bay with a Cummins ISB6.7 and Allison 6 speed tranny with 82000 miles on it. I figured that is just broke in good for a Cummins. First trip had injector 5 go bad. Had it towed to Cummins MidSouth in Memphis and spent $1400 on it.
In the maintenance records left behind by the first owner I found he had replaced #5 three times already, #1 once and #4 or #6 (can't tell which) once.
I need to find out what is causing that and put a stop to it. Company tells me it is probably bad fuel, but I question if that is the case why have the other 3 not failed? They all get the same fuel.
Any possible solutions appreciated.
Thanks

[jimcumminsw]

On most Cummins sites they recommend that you replace all of the injectors at the same time. They also stress to use only Bosch injectors for the fuel system.


I run two filters on my 08 truck; the stock 7 micron and a 2 micron filter after the stock. Buying quality fuel and extreme fuel filtration will insure long life for the injectors.


The 7 micron filter is a Fleetguard FS/2, design part number FS43258. You might need the new filter and shell that was released in around 2010; part number FS43257. Once you replace the shell which is reusable; you will only need to buy the filter. Your 6.7L ISB uses the same filter and shell that I use on my truck.


Jim

[jastarn50]

That sounds quite expensive, but if I do it myself, which I believe I can, it could probably be done for no more than I paid Cummins to replace one.
Thanks for the reply.

[harleyjt]

Originally Posted by jimcumminsw

On most Cummins sites they recommend that you replace all of the injectors at the same time. They also stress to use only Bosch injectors for the fuel system.


I run two filters on my 08 truck; the stock 7 micron and a 2 micron filter after the stock. Buying quality fuel and extreme fuel filtration will insure long life for the injectors.


The 7 micron filter is a Fleetguard FS/2, design part number FS43258. You might need the new filter and shell that was released in around 2010; part number FS43257. Once you replace the shell which is reusable; you will only need to buy the filter. Your 6.7L ISB uses the same filter and shell that I use on my truck.


Jim

Excellent. Just be sure you clean out the filter shell if you reuse it. Dirt and moisture are what kills the injectors and as the OP found out, the injectors for the 6.7 are extremely pricey. I submit to the OP that there is or has been a contamination problem in that fuel system. I suspect it may still be there. The only way to completely fix the problem is to drain the tank, clean it out, and flush the lines. Also need to flush the fuel return system including the return rifle that runs through the head. Once the entire system is clean, start over with a fresh set of Bosch injectors. Also be sure to even clean out the filler neck. Be certain the fuel fill cap seals tightly. Dirt can migrate down into the tank that way. This is exactly the main reason I have a gasser.

Unless the system is totally decontaminated, I'm afraid the OP will continue to have problems and will be replacing injectors periodically. And, I hate to say it, but when these injectors go bad, they start leaking and overfueling. I've seen many melted pistons due to this very failure. Then its a really expensive fix.
jt