CPence

[CPence]

After returning from a cruise three weeks ago my stock (unmodified) 2003 3500 6 speed 4x4 with 113000 miles would not start. No codes in the OBD, so I assumed that it was the transfer pump. The local Carquest was able to get me a new Carter replacement pump, the truck ran for three days then again would not start. I changed the fuel filter (which was black) again it ran for about three days then would not start. A pressure test on the out side of the fuel filter showed 8-9 lbs pressure and low volume. I returned that pump and ordered a FASS DDRP-04 kit to mount on the frame. The truck now runs great but is slow starting, it seems to me that it is cranking longer than it did before my problems (cranks about 10 to 15 seconds before starting).

I want to put a pressure gauge in the fuel line and feel that the gauge shoud be between the fuel filter and the high pressure pump, not on the fuel filter top where it measures the in pressure only. I have gone back through my TDR magazines and can not find where anyone has put a gauge on the line between the filter and the High Pressure Pump, is there a reason that I am missing?

Also in issue 62 of the TDR, HuffnPuff from Springfield VA refures to a check valve in the return fuel line. I have the MOPAR shop manual and cannot find a check valve in the return fuel line (is it the Cascade overflow Valve). Any help and suggestions would be greatly appreciated. C Pence

 

[MMeier]

I call it a pressure relief valve myself. . think cascade overflow is the same . To check it you want to take off the banjo bolt on top, don't lose the sealing washers, and then crank it over, or if it will start, make sure no fuel flows from the valve. If it does, either replace the valve ... or do what many here have, myself included, cap the thing off. Mines been capped for 3 years plus now with no ill effects.

 

[cerberusiam]

Genos Garage has a set of larger banjo bolts with one tapped for 1/8 NPT fitting. Put that on the CP-3 inlet and read your low side pressure there.



FYI, what you had for pressure with the Carter pump was more than adequate. Don't think you have a fuel supply problem. The filter will turn black the minute fuel hits it and it will still be good 15k later, don't use color as an indicator.



AFAIK, the only restriction in the return line system is in the back of the head for the injector return and its just an orfice. Same with the CP-3 and rail relief valve. The COV (cascade overflow valve) is CP-3 internal pressure control only.



Quite likely you have injector problems from the description you posted. You can check the rail PRV to make sure it is not leaking and while you have things disconnected check the injector return volume for excessive flow. Those 2 will give you an idea where to go next.

 

[CPence]

Tried to start it this morning, no luck, it just cranks with not effort to fire. I will order the banjo fitting and a pressure guage from Geno's this morning (it is8:45 AM here in CA). Thanks for the help I will keep you posted. Ches

 

[cerberusiam]

Try some starting fluid and see if that works. If it does you probably have something interfering with rail pressure building correctly.

 

[blacksheepdiesel]

Is the starter turning the engine over fast enough to start? Marginal cranking speed is inadequate to start the Cummins.

Godspeed,
Trent

 

[CPence]

The Batteries are good and the cranking speed is good. I just took the "fuel control actuater" off and it does not rattle like the manual says it should. I put power to it off of the engine and it snaps and moves internaly. I don't know if it is good or not. Is there some way to test it off of the truck. I am open to suggestions. I was told that if sarting fluid hits the hot air grid it could blow the manifold up where do you spray it? (in the air cleaner ?).

MMeier: is the valve that you blocked off the one on the high pressure pump just above the fuel control actuator ?

 

[MMeier]

Relieve valve I capped is located on the fuel rail, if no one else does , I'll try to get a pic here later. Several people sell them here. Not sure how many volts the FCA uses, but IIRC, it is only 5 volts going in, anyone else have any info ? I f thats the case hopefully you didn't zap it with 12+ volts.

 

[CPence]

I did not do anything on the rail only checked the fuel control actuator which is on the back of the high pressure pump. Thanks

 

[MMeier]

Tried taking a pic, but didn't come out in the dark . It is just about in the middle of the rail... if you are by the LF tire looking at the fuel rail, it has the return tube coming off at about the 7'o'clock position, also appears to be the highest point on rail. Like I said before, remove the banjo bolt and spin it over for 10 seconds, or if it does start, look for ANY seepage from there.

 

[blacksheepdiesel]

Have you tried starting with the FCA unplugged? If you do and it starts, shut it off immediately.

Godspeed,
Trent

 

[CPence]

I have not tried starting with the FCA unplugged. Should that make it start if the FCA is defective?

I have the FCA off right now and was planning on ordering a new one from Geno's garage monday.

 

[cerberusiam]

If it is sticky it might help build rail pressure faster. whether or not they rattle if shaken doesn't really tell the whole story. They can be bad and rattle.



To try the starting fluid just disconnect the grid heater relays so it doesn't fire.

 

[TCDiesel]

Try starting Fluid Like Cerb suggested,Just wait until the grid heaters time out or disconnect. In most cases If it runs fine after using SF,the problem is related to Injectors,By the Way T&C has sold over 3000 CPRV and I can only think of 5 or 6 being sold for NO/Slow start condition,Both the FCA/Pressure sensor may cause this But its rare.

 

[CPence]

Thanks for al the input, I am makeing an order to Geno's todawill post the outcome later.

 

[CPence]

It's January 17and I am still waiting for my parts from Geno's Garage, Weather has everything messed up. I will post results when I get more info.

 

[DogramTD]

What conclusion did you finally come to on your truck?