Lift pump on a DMAX?

[Duramaster]

Here's a question. I had a customer ask about adding an inline lift pump to the fuel system. I see that JBPLOCK has an AC DELCO EP-158 installed inline. My concern is does it cause too much restriction? Is there something better without going with the belt driven CP pump? This particular truck is a stock unit used for hauling RV's across country. :confused:

[WILLYD-MAX]

I have installed 3 of Kennedy Diesel's units and they are top notch. Check them out at kennedydiesel.com;)

[jbplock]

Duramaster,

My primary reason for adding the EP158 Lift Pump (http://rides.webshots.com/album/77018086bLHHHC) (EP309 works too) was to prevent vacuum induced out gassing in the large 2micron Baldwin BF7635 (Kennedy Mega Filter) (http://www.kennedydiesel.com/detail.cfm?ID=241), which is plumbed inline after the OEM filter. With out the pump the large filter would loose prime. John has since designed a new nipple for the Mega filter-head that eliminates this problem. However, a lift pump provides other benefits as well. I have the pump plumbed in near the tank with a Stanadyne FM100 30 micron pre filter. The pre filter precedes the pump followed by a tee at the output. The through path of tee feeds the OEM filter and the other output of the tee is routed through a bypass loop with a needle valve to an auxiliary input fitting on the FM100 filter head. The bypass loop with the needle valve acts as a pressure regulator. I use a Kent Moore Vac/Pres gauge (http://rides.webshots.com/album/73314886FLnSco) connected to the Schrader valve near the alternator to set the regulator needle valve for –1hg to 0 psi at the input to the OEM pump. The flow through design of the EP158/309 will also allow fuel flow in the event of a pump failure, which in turn will protect the stock pump from excessive suction load. This arrangement keeps all three filters fuel packed without loading the OEM pump. With the stock vacuum system the OEM filter is only partially full of fuel. (see Suction/Vacuum Side Fuel Filters (http://www.baldwinfilters.com/engineer/pdf/94-6R1.pdf) )

As WILLD-MAX pointed out a better option, which became available after I built my setup, is John Kennedy’s Lift Pump (http://www.kennedydiesel.com/categoryresults3.cfm?Category=3&SubCategory=157&SubCategory2=126).


:)

[Kennedy]

I also do have the GM pump with custom fittings in stainless that screw in directly to the pump (ORB) and install in 1/2" hose. I developed this setup for guys at stock power looking to maintain psi in the system most of the time. My KD pumps are more $$ but a much better solution. Here is the Universal unit:

http://www.kennedydiesel.com/images/ACF47D.jpg

[Duramaster]

And that is my only concern (EP-158/ EP-309). Having seen too many of them fail in the 6.5 Diesel application then causing a low power complaint. Since I'm not an engineer or a scientist (not afraid to admit it either), if the AC Delco pump fails will it cause a restriction? :confused:

[jbplock]

Duramaster,

The AC EP158 (or 309) will still flow fuel if they fail which is the main reason I went with it for my Dmax. I had one fail at about 60kmi on my 98 K3500 6.5TD. The truck would still run but would sometimes stall on startup due to loss of prime. At that time there was some disscusion in the 6.5 forum on the reasons for lift pump failures.The consensus was that adding a pre-filter in front of the pump would pro-long it's life. IIRC the EP 309 has a higher flow rate and a built in pressure regulator as compared to the EP158. The EP309 is also a few more $'s. Since I was adding the bypass regulator I went with the EP158. Iv'e got about 70kmi on my current setup and it's still going strong.

:)

[mattb5150]

I am considering adding Kennedy's Mega filter to my stock '03 LB7, with no plans to add power in the future. Do I need to add an inline pump for a stock power setup with the newly redesigned nipple on the Mega filter setup?

Matt

[DmaxMaverick]

I am considering adding Kennedy's Mega filter to my stock '03 LB7, with no plans to add power in the future. Do I need to add an inline pump for a stock power setup with the newly redesigned nipple on the Mega filter setup?

Matt


The simple answer is no. You do not need a lift pump if you add the Mega Filter. I've been running the Mega (original model) for over 50K miles w/o a pump. I do need to bleed air from the Mega every so often, or it will stall during a cold start after about 1K miles of short trips (lots of cold starts). No big deal, as I (and everyone else) should get under the hood at least that often. Only takes a minute. JK's later Mega models have this issue resolved (IIRC), but it's no big deal if not. Adding a lift pump will eliminate the issue, but is in no way necessary. Good filter choice, BTW. A lift pump would be a very good idea just for priming. Filling both filters after a service is a LOT of pumping, and an electric would be just a flip of a switch. I've planned on adding a lift pump for some time, but I guess it hasn't become inconvenient enough to get serious about it. Still plan on it, but just haven't got around to it.

[Kennedy]

Like DmaxMav stated, lift pump not necessary, but I personally feel that it is a good idea for ANY Duramax.

[Rabbler]

It's a common add on in Northern Canada.
Mostly to add a little Insurance against starvation due to fuel gelling at -50 :eek: