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1987 Fleetwood Brougham
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239 Posts
Discussion Starter #1
I just bought and installed a new fuel pump on my '87 FWB. The old pump's diaphragm broke and it actually hopped off the mounts, so it had to be replaced. The new pump is putting out 11 PSI of fuel pressure and causing my carb to flood. Should I replace the pump again or is there possibly a clog in the return line or something that I should examine?
 

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Registered
1987 Fleetwood Brougham
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239 Posts
Discussion Starter #3
terrible one said:
What carb do you have? You just need a fuel pressure regulator. (regulates the pressure going into the carb)
It's the stock Q-Jet E4MC. I thought about putting a regulator, but shouldn't the mechanical pump only put out 5-6 PSI on its own? Wouldn't 11 PSI mean it's having a valve problem?
 

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1976 Eldorado project
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1,631 Posts
The Q-jets don't like more than 3 psi. Any more will squeeze its way past the float and all.

It depends on what the pump is rated for. Many are rated in the 7-11 psi range. I am going to be running a Holley Red fuel pump which is 1-4, but will also be using the regulator to be keeping it at 2.5 or so.

So what pump ARE you using?
 

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1987 Fleetwood Brougham
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239 Posts
Discussion Starter #5
terrible one said:
The Q-jets don't like more than 3 psi. Any more will squeeze its way past the float and all.

It depends on what the pump is rated for. Many are rated in the 7-11 psi range. I am going to be running a Holley Red fuel pump which is 1-4, but will also be using the regulator to be keeping it at 2.5 or so.

So what pump ARE you using?
I've got some generic Master fuel pump from Advance Auto. It was whatever the computer pulled as the OEM replacement for the car. $17 and change :D

You think I should invest in a cheap $25 Mr. Gasket regulator from the parts store and dial it in to like 3-4 PSI?
 

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1987 Fleetwood Brougham
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239 Posts
Discussion Starter #6
Oh, on a side note, the flooding of the car was related to a vacuum line being disconnected from the carb. It, in a roundabout way, went to the MAP sensor. I'm assuming that if the MAP reads low vacuum in the manifold, it assumes I'm at full throttle and riches me out. I plugged that line back in yesterday and the car runs better than it ever has since I've had it.
 
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