#1 and #4 injector lines pulsing?

[cycletech]

I have 2005 ram2500 with 5. 9L diesel. when i grab #4 and #1 injector lines from rail to injector, they make thumping/pulsing feeling while running, other lines are smooth. what gives?

 

[JBallou]

I know #1 pulses harder than the other ones, but #4 I don't know much about.

 

[JFought]

#4 line and clamp often work loose
i was thinking harmonics, but it could be stronger pulses for cp3...

 

[B.G. Smith]

Try tightening the clamp/support on those two injectors where the little blue plastic blocks support the lines. bg

 

[JJPage]

Try tightening the clamp/support on those two injectors where the little blue plastic blocks support the lines. bg

Number 1 and 6 are unsupported, no clamps. Number 4 often works loose, then breaks or cracks the injector line, causing it to leak, might be good insurance to carry a spare. .



I have not heard a good explanation why #1 has the most pulsing, placement as to where the feed enters? Why doesn't #6 pulse as well, it's feeding from the other end of the rail.



I know Todd from TC Diesel claims his modded rails damper the pulsation considerably, not sure how he determines that, but if he reads this thread he may explain. I've thought for some time, if in fact it does lower the pulsation it may be worth it for that reason alone.

 

[B.G. Smith]

Number 1 and 6 are unsupported, no clamps. Number 4 often works loose, then breaks or cracks the injector line, causing it to leak, might be good insurance to carry a spare. . Mine has supports/clamps on all except #1. bg

 

[JJPage]

On my 03 only 2, 3, 4, and 5 are supported by the little blue plastic clamps, maybe the later 3rd gens received a support on 6, although I do not recall ever seeing one. If your's is supported, I stand corrected, thanks for pointing it out because I did not know that. Jess

 

[Prairie Dog]

I remember someone posting a while back that all but 1 or 2 of the lines has been superseded by newer designs by Cummins so that may be why we have differing numbers of clamps.