CP4.2 Owners Club

[Wayne M.]

Newsa, I’ve not heard of a common rail engine running away for a fuel problem.
I’m a big supporter of letting the tank run very low on occasion, but now I hear it’s not a good idea with this CP4 pump. I’ve also had very good results with “polishing” fuel. I’ve saved many a tank of questionable fuel by using our polisher.

 

[TCDiesel]

Its just a good practice to keep your fuel Tank full on any Diesel engine when convenient.

 

[Wayne M.]

Its just a good practice to keep your fuel Tank full on any Diesel engine when convenient.

Yes, generally speaking. But I treat it like an automatic transmission- either you drop the fluid often, or never at all. I’ve been running my tank down regularly since it was new. My primary don’t even tint from asphaltine.

 

[Newsa]

That's good info.. I guess the old 12 valves also had mechanical injectors too

 

[Wayne M.]

That's good info.. I guess the old 12 valves also had mechanical injectors too

Note of sarcasm there?

 

[Newsa]

Note of sarcasm there?

I shouldn't have used the word "too". Not sarcasm. Just trying to understand the evolution of different gens

I had a friend with a 97 12V 5.9 Cummins (Ram 2500) who said "everything is mechanical". He said even when his PCM died, the engine still ran fine. That made me think that the entire fuel system must be mechanical?

 

[Wayne M.]

Ok, my apologies.
-12valve used a basic full mechanical timed injection. The injectors were pressurized and at a certain pressure, they “popped” off and sprayed at a certain pressure. Other than the solenoid that turned the pump on/off and maybe some timing controls, this was a full mechanical system.




-24valve before 2003 used a similar mechanical pump but with more electronic timing and volume controls, but the injectors are still mechanical.
-24valve after 2003 is a common rail system. This is what we’re dealing with in this thread. If you understand gasoline port fuel injection, you’ll understand this is the same idea, with electronic solenoids on top of the mechanical part of the injectors. The PCM controls the pump pressure at the pump, and the timing and duration of the event at the injector. The pump controls no timing.

Regarding your friends truck, they still used a PCM to control other things like AC clutch, cruise control, auto trans, dash cluster, etc. he was right. You could take the battery out of that truck (if you disconnected the shut down solenoid) and it would keep running.

 

[Newsa]

Still good info. Thx!

 

[R.Taylor]

I miss the mechanical days... A few of my old bikes had a magneto for the spark and a gen to provide 12V to 2 light bulbs. I guess I got fancy when I put a capacitor inline so my lights wouldn't dim and flicker at idle.

 

[Ozymandias]

I dont, way to much maintenance back then, every other day was something to repair.

 

[jhenderson]

I agree with Ozzie. Things were made easy to work on because you had to work on them regularly.

 

[TFucili]

But I didn't have to take the cab off to change points in my old Fords

 

[Signal73]

I missed my ol dinosaur right up until I hooked up to our travel trailer for the first time! My 19 sleeps in a Unheated garage in the winter months, seems like keep the tank full and the stanydyne is recommended. I’ll run it occasionally when the roads are clear from brine and salt to keep fluids moving to where they should go once in a while. Good point about the plastic fuel tanks and condensation.

 

[TCDiesel]

I will try to get a pictures, Customer did NOT follow My recommendation on DO NOT LET YOU TANK DROP TO EMPTY LIGHT, Try to keep 1/4 or more and when convenient FULL. He was traveling long distances pulling a Wagon UNTIL the truck Stalled, the liner inside the Fuel tank melted (Areas) and little pieces destroy his lift Pump Fass (Yep destroying the Fass saved the rest of the HPCR components) because the plastic was found on top of his Fass filters and the factory Canister stopped the rest. At least He took my advice NOT to remove the Factory Canister. When He stalled, He crawl under the truck ( to change filters) and touch the Fuel tank ,that's when he discovered how hot it was, after the tank was dropped , no explanation was necessary were the plastic was from.

The reason I bring this up is because he called today, about this thread, it was back a few years and if he still has the pictures he will be forwarding to Me. 2006 Ram.

 

[Newsa]

I will try to get a pictures, Customer did NOT follow My recommendation on DO NOT LET YOU TANK DROP TO EMPTY LIGHT, Try to keep 1/4 or more and when convenient FULL. He was traveling long distances pulling a Wagon UNTIL the truck Stalled, the liner inside the Fuel tank melted (Areas) and little pieces destroy his lift Pump Fass (Yep destroying the Fass saved the rest of the HPCR components) because the plastic was found on top of his Fass filters and the factory Canister stopped the rest. At least He took my advice NOT to remove the Factory Canister. When He stalled, He crawl under the truck ( to change filters) and touch the Fuel tank ,that's when he discovered how hot it was, after the tank was dropped , no explanation was necessary were the plastic was from.

The reason I bring this up is because he called today, about this thread, it was back a few years and if he still has the pictures he will be forwarding to Me. 2006 Ram.

Does the recirculated fuel coming back from the engine bay cause the hot tank?

 

[Wiredawg]

Newsa, I’ve not heard of a common rail engine running away for a fuel problem.
I’m a big supporter of letting the tank run very low on occasion, but now I hear it’s not a good idea with this CP4 pump. I’ve also had very good results with “polishing” fuel. I’ve saved many a tank of questionable fuel by using our polisher.

Wayne,

Catching this late in the game... I never run my tank lower than 1/4 to 1/2 tank: Reason is from the old 2nd Gen injection pumps. The pump is cooled by diesel fuel and the less fuel at the source, the warmer it gets. Since I tote around 112gal diesel, I make a point to run at least 60 miles a week on my 5500, when primary gets down to around 1/4 tank, open valve, fill primary, shut off valve aux tank valve, refill it, and repeat the process. I've had aux tanks on my truck for 20 years, and this seems to work.

FYI: I had a FASS pump operating as a fuel transfer pump on my former 09 4500. I was in Colorado, going to one of those wonderful campgrounds with the privat lake and beautiful scenery when primary tank got below 1/4 tank. I pressed fuel transfer switch, got busy, forgot it, and ended up blowing out the anti flow ball on the main tank vent and estimate I blew out 10-15 gallons of diesel. Had a nice little trail to my campsite. Anyhoo, I installed 1/2 lines on my 5500 and only use gravity feed.

Great thread!

Cheers, Ron

 

[Wayne M.]

I know Ford has been using a small plate fuel cooler. I forget if it’s coolant exchanger though.
I don’t make terribly long trips, and I don’t see temps like the southern guys do. Probably why I haven’t had a problem.

 

[Ozymandias]

I know Ford has been using a small plate fuel cooler. I forget if it’s coolant exchanger though.
I don’t make terribly long trips, and I don’t see temps like the southern guys do. Probably why I haven’t had a problem.

Many european diesels have that return flow cooler, pretty common.
The fuel tanks are way smaller and so it was a needed addon, its just a little heatsink somewhere along the underbody.

#ad

 

[gsbrockman]

The pic of the 19's filter looks more like a FleetGuard setup to me. It has a replaceable filter element, not a complete filter like the RACOR.

Anyone know the answer to this hot topic???

The 2019 rear separator filter is indeed a cartridge style now. I’ll ask over on CF if anyone has changed their filters on a 2019 yet and see if the rear separator is Fleetguard or another manufacturer.

I had not originally intended in perusing this thread, but I got sucked into it. Appears to be some decent material in here as well.

 

[TCDiesel]

Newsa, First the Owner that melted the liner was running Dual pumps.

When we test our Pumps ( unless for Max when in development) its 1700 RPMs at 8000PSI the compression (fuel) raises the Pump temp+(X) the Pump can get hot to the point the fuel is Now Cooling the pump , the combustion increases fuel by 15-20F @ 8000PSI ( ambient fuel temp ) , It raises the combustion fuel 8-10F for 4000-6000PSI the returning fuel from the Pump at running temps at 1700RPMs 5-8F+increase from inlet fuel, remember the Pump is returning XXX Liters, This is conditional according the Gear Pump and COV Cascade Overflow Valve..Mod these correctly increase many things but it comes at a cost and you had better know what your doing.

Now install the Pump in the Truck .The combustion fuel feeds the Injectors... OK those sprayers are locate just above the Piston holes and those holes get flame temps above 1000s+ Whatever fuel not used for combustion returns to the circuit or valley in the head...Again its hot 160-240+...now its on its way back to Tank. Now the return rate varies according to many thing but I will use the AVG ML at Idle 50ML PM is Perfection ( Don't share this with anyone, it starts arguments and I may NOT be accurate IYNWIM), increase the RPM and the FCA Volts VS Cycle determine the rate to the Rail and Injectors. the AVG return at 1700RPMS 130ML-180ML PM that's a lot of HOT fuel going back to the Tank. On Factory Module the HOT fuel dumps in the the canister to stop the 1/4 run out of fuel when hitting the Brakes or climbing hills. the Factory pump is were! Yep getting ALL that HOT fuel dump right on top of it.

Now consider you have only 4 Gallons of fuel in that tank pulling your wagon for 100s of miles in the Heat of Summer... Hmmmm. its possible for that fuel to vaporize

No what effective does Additive have on The fuel being used flash Point? Clear # 2, Bio-Dsl ,Blended, Whats the refiner additive Package, That's Why I always state to call your local refinery and ask the chemist dept if you should add additives, When it comes to fuel States are like different Countries, the Feds have their standards and the States have theirs.

This is Cummins 5.9/6.7 ONLY.