 Fuel pump pressure relief and checkvalve |
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| saigon71 |
 Nov 30 2009, 10:06 PM
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Advanced Member  Group: Members Posts: 2,000 Joined: 1-June 09 From: Dillsburg, PA Member No.: 10,428 Region Association: MidAtlantic Region 
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Will have time tomorrow to work on the car. 74 2.0 D-jet. Car starts right up cold but requires two taps on the accelerator to keep it from stalling - after that, it runs great. I will be checking the routing of the fuel hoses as recommended by Rich.
Another reply questioned the proper functioning of the fuel pump pressure relief and check valve in the fuel pump. Fuel pressure set at 30PSI when the starter cranks. Pressure drops immediately to 20 PSI when the starter disengages. From 20 PSI, it bleeds down to zero within four minutes...but I have no idea if this is normal. Has anyone taken the pressure relief and checkvalve out of their fuel pump and cleaned/replaced the springs? Is this recommended? Thanks. |
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| davesprinkle |
Nov 30 2009, 11:04 PM
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Senior Member Group: Members Posts: 720 Joined: 13-October 04 From: Berkeley, CA Member No.: 2,943 Region Association: None
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QUOTE(saigon71 @ Nov 30 2009, 08:06 PM)  Will have time tomorrow to work on the car. 74 2.0 D-jet. Car starts right up cold but requires two taps on the accelerator to keep it from stalling - after that, it runs great. I will be checking the routing of the fuel hoses as recommended by Rich. Another reply questioned the proper functioning of the fuel pump pressure relief and check valve in the fuel pump. Fuel pressure set at 30PSI when the starter cranks. Pressure drops immediately to 20 PSI when the starter disengages. From 20 PSI, it bleeds down to zero within four minutes...but I have no idea if this is normal. Has anyone taken the pressure relief and checkvalve out of their fuel pump and cleaned/replaced the springs? Is this recommended? Thanks. The over-pressure relief valve in the pump isn't designed to be serviced. If you open up the crimped can, you likely won't be able to crimp it back together and then you'll have a serious leak. Don't do it. Couple observations: 1. A perfectly tight fuel system, that holds pressure indefinitely, is ideal. And also unrealistic. Bleeding down over 4 minutes is fine. Don't worry about it. 2. You should have 30psi when the engine is running. 20psi isn't enough. Try turning in the adjuster screw on the pressure reg. |
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Posts in this topic
saigon71 Fuel pump pressure relief and checkvalve Nov 30 2009, 10:06 PM
saigon71
Will have time tomorrow to work on the car. 74 ... Dec 1 2009, 10:14 AM
type47 I see your comments about cranking fuel pressure, ... Dec 1 2009, 10:23 AM underthetire If it is bleeding off to fast, probably a fuel inj... Dec 1 2009, 11:27 AM Cap'n Krusty It's doping what it's supposed to do. Jum... Dec 1 2009, 11:47 AM underthetire
It's doping what it's supposed to do. Ju... Dec 1 2009, 11:50 AM swl So back to the original question - he needs extra ... Dec 1 2009, 08:21 PM |
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