Anyone use a fuel cooler? What is a good fuel temperature? Ideas?

[rbattelle]

Its official as of today that my CP3 injector pump is on its way out. The specs for what it should be doing compared to what kind of pressures its putting out are WAY OFF.



I will see if this helps the fuel temps. If not, a fuel cooler is going on the truck asap.



Looking forward to your temperature reports.



Scotty

Scotty,



Was high fuel temperature the cause of the CP-3 failure, or was the CP-3 failure the cause of the high fuel temperatures?



Since the CP-3 was not providing the correct pressures, did you get a check engine light?



-Ryan

 

[scotty1]

I had one code while in Denver... 0251

the dealer there cleared it and told me they thought the CP3 was going to need replacement. It did not occur again even though I had some unusual studders but I think that was caused by the distortion of the in-tank assembly.



So far everyone is of the belief that the CP3 causes heat no matter what but this may make it worse. I guess I will know better after they put a pump on the truck.



Scotty

 

[rbattelle]

Great, another thing to worry about.



-Ryan

 

[nickleinonen]

Great, another thing to worry about.



-Ryan

diddo

 

[rbattelle]

Great, another thing to worry about.

Well, I checked to see if my aftermarket system is causing an overheating condition in the fuel system. After driving around in 100 degree temperatures on the highway for about 30 minutes followed by another 30 minutes of driving through traffic I found that all the fuel lines (supply and return) and the tank were meerly "warm" to the touch. In fact, they were cooler than the body and frame components which had been heated by the asphalt.



So at least I'm not worried that my custom fuel system is causing a fuel heating problem. If the fuel control actuator grenades itself, it's not directly my fault.



-Ryan

 

[rweis]

errrrrrrrr,



What's a CP3 injector pump?



Bob Weis

 

[rbattelle]

What's a CP3 injector pump?

It's what some of us have instead of a VP-44 or P7100.



-Ryan

 

[scotty1]

What I think is happening in my situation is the CP3 is out of spec and dumping more heated fuel back to the tank... and recircualting it over and over since the relief valve is stuck partially open. The lower the amount of fuel in the tank, the hotter it will get.



I wonder if this is what is taking out lift pumps too?



I will check for the heat as well once the new injector pump is on.

Might have been a dud from the factory and is just now showing the worst symptoms. Sorry to stray off the 2 gen topic guys.



Scotty

 

[formula]

The CP3 is not really an "injector" pump.



The CP3 is part of the High Pressure Common Rail fuel injection system that the 3rd gens have. It is a gear driven high pressure pump. It provides high pressure fuel (20,000+ psi) to a common fuel distribution rail. The distribution rail is in turn connected to each of the injectors. The injectors are fired by an electronic solenoid mounted on top of each injector.





Sean

 

[scotty1]

The CP3 is not really an "injector" pump.



The CP3 is part of the High Pressure Common Rail fuel injection system that the 3rd gens have. It is a gear driven high pressure pump. It provides high pressure fuel (20,000+ psi) to a common fuel distribution rail. The distribution rail is in turn connected to each of the injectors. The injectors are fired by an electronic solenoid mounted on top of each injector.





Sean

I agree but as the dealer pointed out... it is ordered as a CP3 injector pump.



The psi on my pump jumped around from 5500-19,000 at WOT.

 

[formula]

oops..... wasn't meaning to pick any bones



A couple of posts up someone was asking what the CP3 was..... Just wanted to give a little better description.



back to the fuel cooler, eh... ...



Sean

 

[MDEJesus]

insted of fuel temp how about fuel condition [ algae-xnet.com] i think that is the site or just google it . anyway from what i have read pumps go bad because of inproper lube from the fuel , then from anything else. hope that helps , diesel forever

 

[scotty1]

No bones, no problemo here.



Kind of like saying its not an APPS its a TPS... we know what it is.

I prefer to report as it is stated from Dodge. I can well imagine if I tried to convey to the tech, service manager or DC that what they are ordering for my truck is really NOT what they are calling it. It could mean an even longer wait.



Latest on my truck is DC canned the CP3 replacement until I get the fuel return volume from the return line at the head measured as well as the fuel return from the CP3. They seem to think its injector related more then the CP3.



Another thing I noticed yesterday while driving on the highway... 1/4 tank of fuel 97F outside, fuel pressure would normally be at 5 with this new in-tank pump at cruise and now was down to 3.



Stopped by my friends shop and aimed the Infra Red at the fuel tank... 177F!

Maybe hot fuel equals thinner fuel... meaning lower pressure.



Back to the dealer on Weds. We had a lengthy talk about all the time I am wasting with them and the tech and all the guessing. Service Mgr agreed and will work something out for me.



Scotty

 

[rbattelle]

It's STILL overheating the fuel, even with a brand new CP-3?



-Ryan

 

[rweis]

Sort of the point of the thread. It is hard to cool with 177* fuel when the VP44 limit is 160* input fuel temp.



I think it comes in 2 parts.



1. More than adequate volume and pressure. The reason I went to RASP is volume and pressure goes up as rpm goes up. When I tow I lockout O/D to get the torque and rpm. Well with a RASP I also get the fuel volume and psi.



2. Fuel input temp ~ 100* or less. The point of returning the fuel to the vent line which is at the opposite end of the tank from the pickup and puting a fuel cooler to get the fuel at least down to ~100* or below. I think the bigger the difference in input temp to operating temp of the Vp44 is the better possibility to keep the VP44 as a whole system (including the electronics bay) cool. The problem with cooling fuel is the latent heat after shutdown that needs to be addressed with ????. But then at least you are no longer generating heat and maybe a simple outside air ducted fan wil be sufficient.



Oh, and a fuel lubricant (I use Stanadyne Performance) in every tank goes with out saying to keep the condition of the fuel above minimum standards.



Bob Weis

 

[scotty1]

It's STILL overheating the fuel, even with a brand new CP-3?



-Ryan

No CP3 yet as DC jumped in when the CP3 was ordered and told the dealer to do these additional tests to rule out injectors or possibly show that both the CP3 and the injectors need to be replaced. They already authorized yet another in-tank pump but the dealer and I agreed that that should be done after the tests and the parts are replaced to see it in fact it is defective or if the pressure comes back up.



I think a temp of 177F is from the recirculating of the fuel at a higher rate then normal. Which must have something out of spec.



Scotty

 

[rbattelle]

I have often wondered if an excessive flow from the lift pump could damage the fuel control actuator. What's the flow rate on the pump you were using when this trouble started?



On the other hand, there is no Dodge or Cummins spec (that I'm aware of) that indicates an upper flow rate limit. (lower limit is 38 GPH)



-Ryan

 

[scotty1]

I have often wondered if an excessive flow from the lift pump could damage the fuel control actuator. What's the flow rate on the pump you were using when this trouble started?



On the other hand, there is no Dodge or Cummins spec (that I'm aware of) that indicates an upper flow rate limit. (lower limit is 38 GPH)



-Ryan

I asked Cummins this and DC and the only answer I got was from a Cummins tech that I emailed, he forwarded me his phone number and we talked about this at length. He was certain that the stock pumps are barely adequate on our trucks and said as long as I am not jamming high pressure, [he said nothing over 15 psi] it will be fine. I even asked the service mgr about this to make sure and he doubted a higher volume pump would cause this problem... so I guess I have a vague answer... go figure... from DC, there was no answer and at least Cummins took the time to reply and help out.



The only thing Dodge said was to measure the flow from the pump at the CP3 in a measuring cup while the pump ran for 10 seconds. As long as it supplied at least 380 ML it was fine.

My Essex pump did that and a bit more.

the new in-tank stock pump was not tested and will be on Weds.

The Holley new out of the box did 110ML. I think it was a dud out of the box.

the original factory pump at the back of the filter housing was lower then the Essex one time and higher the first time but not a lot of difference. The Essex should have pulled over 500 ML.



Scotty

 

[rbattelle]

as long as I am not jamming high pressure, [he said nothing over 15 psi] it will be fine.

That is fascinating... and an excellent bit of information to keep in my back pocket.



-Ryan

 

[scotty1]

That is fascinating... and an excellent bit of information to keep in my back pocket.



-Ryan

Yeah but when I asked why I did not get an answer. I know several folks running 20-25 psi at idle with two pumps with no problems... or maybe they are not aware of it. I ran at 22 at idle [one pump] and I was gradually reducing it when this glitch happened. I had it set right at 15 psi at idle and was planning on lowering it to 12 after the Denver trip but I never got to it before the problem got worse.



Scotty