[jasonlambert]

i was thinking.... our pumps are two stage, so is there one that is weaker than the other. my idea was to bypass the first,low pressure, stage and use a holley blue pump, mainly cause i have one layin around, and then still use the second stage of the pump. any ideas on how this would work?

 

[STurbo90]

What are you trying to accomplish? higher pressure?

The first stage is lower because it feeds the fuel bowl, after leaving the fuel bowl it goes to the second stage to increase the pressure.

If you feed the fuel bowl with high pressure it will leak, I believe the first stage is only 10 lbs.

 

[jasonlambert]

i know this holley is only 15 max. i am trying to help w/ pressure drop not get it higher. just wondering which stage of te pump is the weakest link

 

[thedieselkid]

If you are gonna go that far, you may as well just put an electric fuel pump on it and ditch the stocker.

 

[jasonlambert]

lol i know but i could do this for free as a temporary setup..... if it would help anyway

 

[jasonlambert]

so does any one know if stage 1 or stage 2 of the pump is the weakest?

 

[BlueMule]

I've changed out two of them, both because the piston stage was gone.

 

[jasonlambert]

sorry, is that the first or second stage?

 

[BlueMule]

1st is diaphragm, 2nd is piston.

 

[jasonlambert]

you do not think it could be cause the first stage was lacking and it burned up do you? loljust a thought before i give up on it

 

[BlueMule]

I dont know what the 1st stage is supposed to be as far as pressure but mine was still at 6-7 psi. I wonder if shimming the regulator above the factory preset of 46psi it what's causing some of the failures in the 2nd stage?

Even with no pump (actually an electric pump that is electrically disconnected) the PSD will start up and idle just fine. So I dont think your Holley blue is needed and it's 15 lbs of pressure may be more than the fuel bowl will take without leaking where the sensors pass thru the body.

 

[jasonlambert]

ok thanks just thought i'd try lol since it would be free thanks for not allowing me to waste time actually doing it


i guess it may help if your pump was bad to stop the pressure from going to zero cause w/ 2 regulators set to 7 that is what it will hold wot w/ a 950 holley double pumper

but mine is good so no use

 

[danjreed]

[ QUOTE ]
.... wonder if shimming the regulator above the factory preset of 46psi it what's causing some of the failures in the 2nd stage?...

[/ QUOTE ]
Mine wasn't and isn't shimmed, I did the fuel pump about a month ago. It was leaking when I got it. Possibly the original pump given the amount of debris surrounding it.