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CP3 fuel supply

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48re troubles need help

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EZeis

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I've been thinking about adding a 2 micron filter and a 8 micron water separator (heated) between the CP3 and the OEM filter/heater assy. With the OEM lift pump. Both fleetguard, FS1212 and FS1003. BTW, truck is stock down to the air filter.



I've read all the threads on 2 micron filters and pressure drops and such. My question is what happens if the lift pump fails with the OEM system system? Does your CP3 burn up? What happens if the OEM filter plugs? Does the CP3 burn up?



I've heard GM trucks run the CP3 without a lift pump. Good sign the CP3 won't burn up easily.



So if adding more filters to the OEM system with the OEM lift pump, wouldn't you have engine performance issues long before you waste the CP3?



I may have overlooked this, I didn't see much mention on the CP3 fuel supply specs. I would think as long as you have flow even 0 psi, the CP3 would still be able to build high pressure for the rail.



Anyways, I guess that's what I'm really after, the CP3 fuel supply specs and what happens with low or no flow and what kills these pumps?



Thanks,

Earl
 
It is said you won't burn up the CP3 with no fuel going to it. Yes the Duratrashes run with no fuel supply. Do a search this was just discussed on the 3rd genners forum. I think it's risky with the stock lift pump . Just my . 02
 
Take a look at the link in my sig... from all the research I did its the best way to go. And when the OE LP fails the liberty mod and a external LP will easily go between the BF1212 and the OE Canister.

The FS1003 is not a 2um filter thou, its a 10um filter.

What are you planning to do for heating the fuel? I want to add a heater to mine.

To answer some of your other questions. The CP3 has the ability to draw fuel, so unless there is an abnormal failure of your LP the CP3 will suck fuel thru it, maybe not enough for full power, but enough to get you home. . in theory. The CP3 only needs flow, not pressure, to operate. The Bosch specs on flow are -5 to +15psi.
 
Anyways, I guess that's what I'm really after, the CP3 fuel supply specs and what happens with low or no flow and what kills these pumps?



Unofficial specs for the Dodge configuration is +3 psi at the CP3 inlet for stock fueling, for higher HP tunes that will have to go up or the flow is not adequate to supply the needed case pressure. An OFFICIAL number is not available becuase neither Cummins nor Bosch will commit to something like that and and be held to it. ;)



Don't get sucked into the "Duramxes don't have a lift pump" theme either, they may not have an LP but they suffer more issues and power loss than the Cummins engine becuase of it. Fuel line size, tank placement, etc, are all different when comparing the Chevy and Dodge platform. Don't believe it when it is said a CP-3 will run a 0 psi becuase thats a balance point. Simply not true.



Will the pump "burn up" from lack of fuel? Short answer, no. However, thats not where these pumps damage themselves the most. The supply pump in a CP3 is a gear rotor pump that can suck its own fuel supply if needed but thats not what it is designed for. With any pump of this type a head pressure is needed to stop cavitation in the pump. Cavitation is THE single worst problem the pump faces and will do more damage than anything else. With the CP-3 it beats up the drive end of the pump shaft and spits metal shavings into the rail supply and pump lube supply. Guess how long a pump lasts in those conditions?



The secondary result of low supply pressure is fuel is prioritized to the rail. When case supply drops below optimal lube\and cooling is slowly reduced until a balance is met. Little to no flow thru the pump is going to promote heat and wear, period. The CP-3 will last much longer with an adequate lube\cooling supply.



There is no easy or short answer to how much pressure is enough, that is dependent on what is going in the pump, down stream of it, and supply line size. The only way to know for sure is a rail pressure gauge and a case pressure gauge. What has worked both for stock and performance applications is a constant 15 to 35 psi at the CP-3 inlet. The CP-3 can take as high as 100 psi inlet pressure with no issues so the high side is generally not a problem. The low side of the pressure is the crtitical point, in this case more is DEFINITELY better than less, even though less may suffice.



If that isn't confusing enough we could throw entrained air into the equation and look at its impact. :-laf
 
What are you planning to do for heating the fuel? I want to add a heater to mine.



This is the water sep with built in fuel heater I'd like to use. The heater is between the filter and the head assy. Also the filter has a water probe on the filter that can be wired to light a LED or bulb if you wanted.



Earl
 
How about just a water separator between the CP3 and OEM filter? Like a high micron rating of 20? Water is my biggest fear as the OEM isn't a real sepearator. Do they make a water separator without a filter?



Earl
 
How about just a water separator between the CP3 and OEM filter? Like a high micron rating of 20? Water is my biggest fear as the OEM isn't a real sepearator. Do they make a water separator without a filter?

Earl

Why do you feel the OEM isn't a real water separator? Its rated better than just about all the aftermarket f/w seps are (Like FASS and AD).

I would put an additional f/w sep before the OE canister, just like how my BF1212 is.

You need filter media to remove water, so no you have to have a filter to separate water.
 
Why do you feel the OEM isn't a real water separator?



I've seen and heard of water getting past the OEM separator and destory the whole injection system. There have been posts on TDR of this happening as well. I never get any water out of mine nor has the light ever come on. I don't trust the thing.



Earl
 
I've seen and heard of water getting past the OEM separator and destory the whole injection system. There have been posts on TDR of this happening as well. I never get any water out of mine nor has the light ever come on. I don't trust the thing.



Earl



The factory filter, Donaldson Cross, and Baldwin Cross are all rated at 98% free water separation and 95% emulsified water separation; on the same standard that the FS1003 and FS1212 you listed are, in fact the OE filter is rated for more free water sep than either the FS1003 or FS1212. .



I have 2 f/w seps on my truck that are both rated at 95% or better for free/emulsified water sep and I haven't seen a drop of water in 40K miles. Modern fuel is much better than it used to be, but there are still bad batches out there, hence my excessive filtration, but I have been very lucky.



The OE WIF light is less than adequite, it takes a lot of water to set it off, and needs to be cleaned. I think most people don't clean it, which makes it less effective, or inoperable and then the driver has no way of knowing that they have water getting thru.



The other issue I see is people run cheap filters, which probably don't separate water as well. The only 3 filters I have found to meet OE spec are the ones I listed above. . the rest don't.
 
I want to add a heater to mine.

Why do you feel the OEM isn't a real water separator? Its rated better than just about all the aftermarket f/w seps are (Like FASS and AD).

The implication is that you've eliminated the stock filter canister. Why?

Even after all these years and countless threads on the subject, I cannot understand the reasoning behind eliminating the stock filter canister. Well, I suppose maybe if you're building a pulling truck and need to minimize restrictions, but then filtration, water separation, and heating wouldn't be your major concerns.

Ryan
 
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The implication is that you've eliminated the stock filter canister. Why?



Even after all these years and countless threads on the subject, I cannot understand the reasoning behind eliminating the stock filter canister. Well, I suppose maybe if you're building a pulling truck and need to minimize restrictions, but then filtration, water separation, and heating wouldn't be your major concerns.



Ryan



I run it, I have 3 filters. . one of them is the stock canister with the PF7977. . But I want a heater for the 1st filter.
 
I run it, I have 3 filters. . one of them is the stock canister with the PF7977. . But I want a heater for the 1st filter.



Ah yes, I see now. And the fact that there's one before the stock canister explains the desire for an additional heater.



Ryan
 
Hot fuel do not give you as much power as cool fuel. That is they have laws on the temp of gas at the pumps. I don't thank they have a set temp on diesel fuel as of now. It has ben talked about.
 
Thats not true either, diesel has a temp range that it is the most efficient in and thats what the fuel heaters are trying to address. Temp at the pump is beyond the scope.



Diesel fuel combustion efficiency is best between 85 and 110 degrees with 100 degrees being the optimal point for injection.
 
Hot fuel do not give you as much power as cool fuel. That is they have laws on the temp of gas at the pumps. I don't thank they have a set temp on diesel fuel as of now. It has ben talked about.



My understanding on why they have temp laws at the pump is that hot fuel does not give you as much VOLUME of fuel, due to the relation between temperature and expansion, not temperature and HP.
 
Hot fuel do not give you as much power as cool fuel. That is they have laws on the temp of gas at the pumps. I don't thank they have a set temp on diesel fuel as of now. It has ben talked about.



Trust me, when it's 5 degs out you want fuel heaters or you won't be going anywhere. Also fuel heaters warm the fuel, not make it hot. Also fuel heaters only come on when needed.



Earl
 
Trust me, when it's 5 degs out you want fuel heaters or you won't be going anywhere. Also fuel heaters warm the fuel, not make it hot. Also fuel heaters only come on when needed.



Earl



If its properly winterized heaters aren't necessary. . I ran just fine at -13*F this winter with good fuel, and gelled at -2*F with bad fuel.
 
If its properly winterized heaters aren't necessary. . I ran just fine at -13*F this winter with good fuel, and gelled at -2*F with bad fuel.



I'd rather not gamble and most OEM's don't either since they install fuel heaters. lol Been driving diesels for almost 20 years and never had a filter wax up or gel yet and I don't use treatments. Filter waxing will start before the fuel gels. Once fuel gels, no fuel heater will help you as it won't pump. Also warm fuel flows more freely through a filter than ice cold fuel. We can't run our power plant without our fuel heater at work. The pressure drop across the filters in the tank farm is so high with ice cold fuel our engines drop out. We run a 50KW 3 phase fuel heater and its just as sweet as it sounds. lol We run 48 60 series, 16MW worth.



How many miles and years or hours have you been running your extra filters on your OEM LP?



Earl
 
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