New duralift running at 3psi

[Meatloaf326]

Hey all,

Today I replaced my Holley red that ran key on at 6psi. I went with the Duralift 40285 supposedly for reliability but it won’t give me more than 3psi. I had ordered 2 to have a spare so I swapped them and same result.

All pumps were mounted in the same place, about 2 feet in front of the tank selector. New fuel filter as well. Also I have checked grounds and power
What’s going on?

 

[silverrex4]

How is your tank pump? In the site glass is it completely full? Any debris at the bottom. You can use an air and blow back into the tank to see if there is a restriction. That pump should be clacking away.

 

[IDIBRONCO]

You went backwards. Most people try the Duralift first because they're cheap. Then they find out that the pumps won't supply enough fuel so they go away from the Duralifts.

 

[hacked89]

Reverse fuel evolution

 

[ROCK HARVEY]

3PSI is actually right within spec for the DB2 injection pump. Per the manual:

“Vacuum at the transfer pump inlet must be avoided. If an auxiliary pump is used, pressure at the transfer pump must not be less than 0 p.s.i. nor greater than 5 p.s.i.”

(The transfer pump it’s referencing is is inside the injection pump)

Just make sure that you’re staying above zero PSI at full throttle and you should be fine. FYI I’ve been running the duralift 40222 for 18 months without issue, but I’ve seen plenty of threads where people reported issues.

 

[ROCK HARVEY]

Here’s a link to the manual for those interested: https://radionerds.com/images/f/f4/Stanadyne_db2_operation_and_instructions_manuals.pdf

 

[Austin86250]

You went backwards. Most people try the Duralift first because they're cheap. Then they find out that the pumps won't supply enough fuel so they go away from the Duralifts.

I learned that the hard way, I’m not sure how people get such good results from them, I was unable to replicate it with 2 models

 

[Clb]

Search function fail
The Standyne db2 manual is in the tech 101 section.
The how to time yer idi
Timing a 6.9-7.3
And much more touch upon fuel pressure.
There must be a 6 pac of e pump threads on here....

 

[Meatloaf326]

I went back to the Holley and I’m back at 6psi and it runs down to 3psi.

I guess I overthought my fuel situation and jumped the gun without doing my homework!

 

[IDIBRONCO]

I’m not sure how people get such good results from them,

My guess is that every once in a while, Duralift messes up and makes a good one. Nobody's perfect right?

 

[Cubey]

3PSI is actually right within spec for the DB2 injection pump. Per the manual:

“Vacuum at the transfer pump inlet must be avoided. If an auxiliary pump is used, pressure at the transfer pump must not be less than 0 p.s.i. nor greater than 5 p.s.i.”

(The transfer pump it’s referencing is is inside the injection pump)

Just make sure that you’re staying above zero PSI at full throttle and you should be fine. FYI I’ve been running the duralift 40222 for 18 months without issue, but I’ve seen plenty of threads where people reported issues.

My RV didn't like unregulated pressure from Holley Red, even with the fuel passing through a Racor W/S filter plus the stock 6.9 filter. Had to put a dial style regulator, set to 3psi, to fix it.

 

[ROCK HARVEY]

Interesting side note: Holley has started selling the duralift pump re-branded as the Holley Mighty Mite 12-430.