Superhuman Lift Pump on Steroids!

[DEZLPWR]

I got my Westach fuel pressure gauge in this weekend (thanks Dawg-1!)and noticed that my new (less than 1 month)lift pump must be on steroids or something. At idle I am showing a steady 15-15. 5 psi and at various speeds and RPM's going down the road I am showing pretty much a steady 14 psi. I got it down to 11psi today by really nailing the throttle, but as soon as I let off it went right back up to 14psi.

Is anyone else seeing readings like mine? I'm certainly not complaining, I just haven't seen other TDR members with similar readings.

I am also curious to see how long the pump will continue to put out these high PSI readings.



Just wait till i get the Comp box and DDII's!



Bombitis has hit me hard, and I don't think there is a cure for it.



Steve

 

[RustyTRanch]

Mine was 14 when new,

never below 12

It has been going south slowly

now 11 at idle

and 8 loaded

I am ordering a spare-

H*!! with warranty

they are idiots

later

mike

 

[24V-DSL]

Oh...something else

Steve... .



Did you use the 3990105?



I bought one at the same time I bought my fp gauge, thinking that after the install of the gauge if the numbers were lousy, I'd just put on the new 3990105.



To my suprise, my readings with my factory pump are very good per my Autometer 0-15psi. Truck has 18K miles.



Idle = 14. 5



50-65mph = 13-14 consistent



WOT = as low as 7, but more often 9-10. That's of some concern, but I don't go to WOT all that much, and at "aggressive acceleration" I get 11-13, so I'm thinking that's ok.



Also, Ray T. banjo's were installed at same time as gauge, and I suspect they are helping the good numbers, but of course have no way to prove this since I had no readings with the stock banjo's.

 

[DEZLPWR]

Yeah, I got the 3990105 lift pump from Cummins along with the wire harness that is needed for the 99's and 98. 5's.



Steve

 

[DAWG-1]

Great ....

I was surprised at the pressure. That is a nice gauge and sender. Your welcome Steve. Sam

 

[Devildog]

I wonder how your pump will do with an ultimate fuel module with the DDII's, at WOT my pressure goes down to 6 psi.

 

[Ron Bissett]

Re: Oh...something else

Originally posted by 24V-DSL

Steve... .



Did you use the 3990105?



I bought one at the same time I bought my fp gauge, thinking that after the install of the gauge if the numbers were lousy, I'd just put on the new 3990105.



To my suprise, my readings with my factory pump are very good per my Autometer 0-15psi. Truck has 18K miles.



Idle = 14. 5



50-65mph = 13-14 consistent



WOT = as low as 7, but more often 9-10. That's of some concern, but I don't go to WOT all that much, and at "aggressive acceleration" I get 11-13, so I'm thinking that's ok.



Also, Ray T. banjo's were installed at same time as gauge, and I suspect they are helping the good numbers, but of course have no way to prove this since I had no readings with the stock banjo's.

Larger ID will not increase PSI restriction will increase PSI . Pumps make flow restriction to flow makepreassure, The readings ? post filter or Pre filter. Ron in Louisville Ky

 

[24V-DSL]

Oh-oh

Ron... .



the readings are post filter. Now you and the rest of the TDR know my ignorance about fluid pressures, etc.



The edit on my original post was the addition of the Ray T. banjo bolt stuff



At the time I thought it was kinda brilliant... .



Joe

 

[Ron Bissett]

Re: Oh-oh

Originally posted by 24V-DSL

Ron... .



the readings are post filter. Now you and the rest of the TDR know my ignorance about fluid pressures, etc.



The edit on my original post was the addition of the Ray T. banjo bolt stuff



At the time I thought it was kinda brilliant... .



Joe

Joe I did not in any way try to sharp shoot you just wan't to know how pressure was taken, and for any other readers, that read post that do not know much about the subject. How and why on the Lift pump, or some times called a transfer pump, Whats going on . Thats how we all learn . Keep on posting, and others out there, let us know your thoughts . Saves $ if informed. We need all the help we can get . Thanks Joe . Ron in Louisville KY

 

[24V-DSL]

Thanks, Ron

Absolutely no offense taken, Ron



Well. gotta run, it's time to change the air in my tires.....

 

[GBerry]

Good Idea!

Well. gotta run, it's time to change the air in my tires.....



air in my tires have almost 30k now guess I should have changed it by now !!!

changed my tires air the last time I was at the Sand Dunes a couple of weekends ago buried it real good (first time I wished I had held out for a LSD ) got the trailer hung up trying to get out of the way of someone else trying to get bye in one of the trails to the camping spot we like to frequent

Guy

 

[B. Gill]

can any one please tell me what is the easiest way to change air in my tires and i have over 42k on my truck?

also any possible damage that may have been done due to not changing it so far