Relentless Diesel fca mod

[robertyoke]

I have had allot of surging lately from my 03 truck and it has been getting worse. When the throttle is held at a steady rate the rail pressure changes, rising and falling like 3,000 psi. It is worse when the truck is cold but even warm it never goes away.



I have been reading the latest posts about the fca (fuel control actuator) and I was going to order one from cummins. (now that I got a part number) I saw the post about the relentless mod and I figured what the heck ..... right. If I wreck it I'm only out the time it took and 100 bucks for the one I going to buy anyway.



I took it out and did the mod. and with the exception of dropping one of the torx bolts into the frame rail, it was straight forward. The fca did not rattle when I shook it. It also didn't fall out with a few taps. I did pull it out with a little screwdriver wedged against the triangle holes. I did notice that my piston has some galling on one side like it is wearing unevenly. I did the mod and sanded it with some 600 grit wet/dry emery cloth.



I fired the truck up and went for a drive. I can say that that this truck has never been this smooth. It does not have any surge whatever. I can't say there is any more power with the butt-o-meter. Maybe more smoke from a dead start and the rail pressure is more constant and just a tad higher with the tst and the smarty on the same setting.



Thank you Relentless for the mod!



I will do the gear case when I get a chance!



-robert

 

[mberry]

Can you post some pics or a link please? I'm not familiar with this mod.

 

[COSEng]

How many miles on the 03?



How hard was the plunger to cut with the dremmel? Would it be easy to cut too much?



Were you having high idle issues in warm weather, hard starts, etc. , or just low power?



Glad to hear it was a success.



Carl

 

[Cattletrkr]

The fca did not rattle when I shook it. It also didn't fall out with a few taps. I did pull it out with a little screwdriver wedged against the triangle holes. I did notice that my piston has some galling on one side like it is wearing unevenly. I did the mod and sanded it with some 600 grit wet/dry emery cloth.

What is supposed to rattle or pull out? I've read that before too. The new ones (mine and dad's '03) I installed a few months ago had no loose moving parts. They were identical to the old ones only cleaner.

 

[robertyoke]

Can you post some pics or a link please? I'm not familiar with this mod.

here is your clicky http://relentlessdiesel.com/forum/viewtopic.php?t=19

 

[robertyoke]

How many miles on the 03?



How hard was the plunger to cut with the dremmel? Would it be easy to cut too much?



Were you having high idle issues in warm weather, hard starts, etc. , or just low power?



Glad to hear it was a success.



Carl

It was easy to cut with the dremmel... well cordless drill with the dremmel attachment.



no other problems other than surging. it was annoying!











"What is supposed to rattle or pull out? I've read that before too. The new ones (mine and dad's '03) I installed a few months ago had no loose moving parts. They were identical to the old ones only cleaner. "



The piston is supposed to rattle when shaken and when you take it apart it should just about fall out. Take a look at the clicky above.



-robert

 

[steved]

The piston is supposed to rattle when shaken and when you take it apart it should just about fall out. Take a look at the clicky above.



-robert

While this might have been the"norm" at one point, almost every post I have read about replacing the FCA indicated they no long rattle when shook, and therefore, that "test" is not a reliable one to determine pass/fail for the FCA.



I wonder since I read several FCA numbers, if theyb have been upgraded so that they don't incur the wear you noted on your FCA????



steved

 

[steved]

I just got my new Cummins FCA, and it does not rattle...



The Bosch PN# is as follows:



0 928 400 666



followed by:

25504

68518



Cummins PN# is 4932457 (this is a repackaged Bosch part)...



Looks like I got an updated (read: current) part... the package date is 17 August 2006...



steved

 

[GOT-Torque]

what sort of hp gain would be expected with both mods listed in the link above?

 

[steved]

what sort of hp gain would be expected with both mods listed in the link above?

I would assume that this mod would benefit someone running a box/chip that's pushing more than stock HP levels...



I was wondering what it might do to mpg... probably nothing since the injectors pretty much control that...



steved

 

[Bob Wagner]

The new beta 4. 2 smarty software is really showing great results on the 03/04 trucks. The 04. 5 and up is rock solid too

 

[drasko]

ok sorry to resurect this thread but im gonna do this relentless mod and want to order a new FCA and the gear case so i can drill and try them out..... i have the FCA PN# but does anyone have one for the gear case? ive searched quickserve but cant find a number for it!!

adam