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    #16
    Damn check valves... Common problem for the Jeep XJ's too. I know mine had this issue. It was worse in the winter.

    I've been wanting to get a fuel pressure gauge, now I've got an excuse to get one... Well, another one. I had one but somehow lost it, or it got swiped.

    So, if that's the problem and pressure bleeds off after shutdown do I need a whole new pump? I know that what ever it's got for a pump right now is loud as hell. Thing whines, sounds like a terrible air leak that can easily be heard outside the car while it is running. I hate it. Its about the same volume as my exhaust when at idle. That normal? Or does that sound like my car has a cheap replacement pump in it?

    I should also note that the car still has the fuel filter that was on it when I bought it. Been meaning to change it, got the replacement in the trunk... But I haven't quite figured out how to yet. Funky set up on this car.
    1987 Lincoln Town Car Signature Series-102k miles- LOPO 302, AOD, open 3.27, Dual exhaust w/ Thrush Turbo mufflers

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      #17
      Fuel pressure regulator as well?... Hmm, I wonder how to test that. Other than just replacing it.
      1987 Lincoln Town Car Signature Series-102k miles- LOPO 302, AOD, open 3.27, Dual exhaust w/ Thrush Turbo mufflers

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        #18
        The fuel pressure gauge will tell you about the check valve and the regulator, to a point. A chain auto parts store will likely rent you the tool if you don’t want to buy another.

        I haven’t seen the check valves serviced separately from the pump. If your pump is loud, and the check valve proves bad, I think I’d replace the whole assembly. The stock pump in my 88 is near silent. The spectra in my 90 is not as quiet but certainly not noticeable over the stock exhaust.
        1990 Country Squire - weekend cruiser, next project
        1988 Crown Vic LTD Wagon - waiting in the wings

        GMN Box Panther History
        Box Panther Horsepower and Torque Ratings
        Box Panther Production Numbers

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          #19
          Could also be a split line inside the tank. If you're dropping it to fix either, change the pump. Its not that spendy.

          FPR usually is reliable but if you pull the vac line and its got fuel in it, dead. Can't easily pinch the return line shut to test it otherwise. The flexy lines are plastic and don't really respond well to being pinched shut. Maybe someone makes a dummy plug that lets you unplug the return line for testing that way.
          86 Lincoln Town Car (Galactica).
          5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley

          91 Lincoln Mark VII LSC grandpa spec white and cranberry

          1984 Lincoln Continental TurboDiesel - rolls coal

          Originally posted by phayzer5
          I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousers

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            #20
            Yea, it'll just show if it is bleeding down after shut down, and how fast the pump builds it back up... And of coarse running pressure. Yea, I'll probably just buy another gauge to have in my shop.

            Hmm, I was kind of figuring that the check valve wouldnt be serviceable, but ya never know without asking.

            So, I should just to ahead and get a new pump? What brand is good, reliable, and quiet? This has got to be the loudest pump I've heard on a vehicle. I used to wonder if something was wrong with it but, I have no running problems. Just the long crank/starting issue.

            Split line in the tank? How do I fix that? Is that a line that Would come with a new pump assembly? Or part of the sending unit? Sending unit in my car works fine, I wouldn't want to replace that.

            Pull vacuum line to the fpr, that's easy enough for a test. I'm going to have to look at things in person to see what ya mean otherwise... When I get a guage on it, what's the fuel pressure supposed to be on one of these 302's?
            1987 Lincoln Town Car Signature Series-102k miles- LOPO 302, AOD, open 3.27, Dual exhaust w/ Thrush Turbo mufflers

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              #21
              diag it first. no point in dropping the tank if there is nothing wrong with it.

              The line in the tank is a 6" piece of rubber hose. It clamps on. When the pump hanger is out the hose and how to change it is pretty obvious. Just get hose rated for in-tank use. I don't know the number offhand but its apparently different than regular EFI hose.

              running pressure with the vac line on the regulator is 30-35, no vac line 40-45.
              86 Lincoln Town Car (Galactica).
              5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley

              91 Lincoln Mark VII LSC grandpa spec white and cranberry

              1984 Lincoln Continental TurboDiesel - rolls coal

              Originally posted by phayzer5
              I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousers

              Comment


                #22
                Your symptoms sound like mine, I know my FPR is bad, and there are a few vacuum leaks. I was going to replace the FPR but it wasn't possible to pull it without also pulling the upper intake. I'm swapping the engine in the not too distant future so I just put the FPR on the shelf to use with the new engine and I'll put up with the issues for now.
                1986 Country Squire
                1969 Mercury Cougar
                1960 Land Rover Series II 88"

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                  #23
                  Oh yea, I'll diagnose it first. I hate dropping gas tanks. Though this car don't look so bad compared to the others I've done.
                  For some reason I was thinking of a metal line. Rubber line is easy for replacing.
                  Thanks for the running pressure specs.

                  I still haven't done much with it yet. I've been busy with work and have a lot of other projects lined up before the car. As long as the car keeps running good, than it can wait. So the fpr can't be pulled without pulling the intake? Good thing I haven't pulled it yet!

                  Thanks guys for the info and help so far.
                  1987 Lincoln Town Car Signature Series-102k miles- LOPO 302, AOD, open 3.27, Dual exhaust w/ Thrush Turbo mufflers

                  Comment


                    #24
                    Mini update to this. I don't remember all of what I've done since the last post but the car has been doing better. I did a little more diagnosis and didn't find anything too far off.

                    I finally changed out the fuel filter last week. In 33 years and almost 100k miles, I don't think it has EVER been changed. It was stuck good, rusty and had some weight to it when I pulled it out. The new one is so much lighter, don't know if it's a lighter filter or if the old one is just full of junk. Here's what I do know though. After changing that filter I no longer have to double prime (with the key) before starting. It starts just fine- for now.
                    1987 Lincoln Town Car Signature Series-102k miles- LOPO 302, AOD, open 3.27, Dual exhaust w/ Thrush Turbo mufflers

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                      #25
                      I usually dump the old filters out into a can just to see what sort of crap comes out.
                      86 Lincoln Town Car (Galactica).
                      5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley

                      91 Lincoln Mark VII LSC grandpa spec white and cranberry

                      1984 Lincoln Continental TurboDiesel - rolls coal

                      Originally posted by phayzer5
                      I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousers

                      Comment


                        #26
                        ^Still haven't done that yet, but I still have the old filter on the bench

                        2021 update!
                        Couple of days before I legalized the car for road use this season I changed the oil and checked the other fluids. Checked the operation of the a.c. and went for a short drive on the property. Damn thing stalled when I came to a stop?! Only time it did it though. Been daily driving the car this last week and hasn't had any idle speed problems- then again I haven't been using the a.c. either.

                        What I do have back as a regular problem is extended crank times while getting it started. That's even with double priming the fuel pump. It'll crank for a minimum of 2 seconds before starting and other times up to an estimated 5 seconds. That seems excessive to me. What's normal for these fi cars?

                        Lets get this fixed.

                        So, I picked up a fuel system pressure gauge from the local HF. Checked both my Cherokee and the Lincoln. The Lincoln's readings are kind of odd. Not sure if the problem points to the regulator, a fuel injector or the pump/check valve or a mixture of the 3.

                        When attached, I had no fuel come out. Primed it once, pressure didn't register... Second prime, gauge went up to 5psi.
                        Now- I'm going off memory here... Third prime, gauge went to 10-15psi then started to drop... Fast. Forth prime, it shot up to 39ish psi and dropped fast. Fifth prime, went to the same 39 so I started it that time. Started up fast... But I don't want to have to prime it 4 times everytime I go to start the car...

                        When running, the gauge was reading a solid 30psi. If I revved it the gauge would shoot up a bit to between 35 and 40. When it came down from a rev it would dip into the upper 20's, then settle back to 30psi.

                        Shut the car off. Pressure went back down to 10psi rather quick and slowly from there went back to 0. Slowly as in a few minutes. Went to start it again, pressure went up to 10ish psi and it fired up after some (my normal)crank time.

                        Here's where it gets a little weirder. When shut off again it held pressure much longer. Took like 5 minutes to go down from 30. I walked away and ate my lunch. When I came back it was down to 0, But when I pulled the gauge off it did squirt a little fuel out.

                        That's my findings. The car had an oil change about 2 weeks ago and didn't smell of fuel so I'm not thinking fuel injector. FPR is vacuum controlled and with running pressure looking like what it is, that seems to be operating properly. Can they still bleed it down though, when the system is off but seemingly operate fine while on?
                        Fuel pump to me is highly suspect. Seems to be on the weak side, and this is the pump that is as loud as the exaust at idle. I don't know if that's a sign of an obvious problem or not.

                        What's everyone's thoughts?
                        1987 Lincoln Town Car Signature Series-102k miles- LOPO 302, AOD, open 3.27, Dual exhaust w/ Thrush Turbo mufflers

                        Comment


                          #27
                          FPR would be a cheap and relatively easy try. Otherwise I'm looking at the fuel pump and related stuff in the tank.
                          1990 Country Squire - weekend cruiser, next project
                          1988 Crown Vic LTD Wagon - waiting in the wings

                          GMN Box Panther History
                          Box Panther Horsepower and Torque Ratings
                          Box Panther Production Numbers

                          Comment


                            #28
                            I had similar problems in my 87 mgm for as long as I’ve owned it. I did all the checking you did and it had healthy fuel pressure running but didn’t hold pressure when off or would drop low and stay there. One day I said screw it and replaced the pump and now it starts on the first crank. If it’s the factory pump I’d recommend changing it anyway.


                            Sent from my iPhone using Tapatalk

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                              #29
                              If its dropping rapidly and priming slowly the fuel is going somewhere. Possible its the FPR, could be a stuck open injector, could be the check valve in the pump. The way to see if its the FPR is you close the return line off, but the right way to do that is with a dummy plug that goes in that end of the fuel rail. The line itself is metal except where its hard plastic, and you really don't want to pinch that plastic or it creates weak points where its likely to fail.

                              If the pressure still drops, its not the FPR. The fact that it comes up to the right pressure makes me think the regulator is probably OK. If you want to check for leaky injectors, pull the plugs. If you find one thats wet or at least obviously darker, thats a pretty good clue. If both of those things check out good, my money is on a pump problem.

                              frankly with zero further diagnostics, my money is still on something in the tank.
                              86 Lincoln Town Car (Galactica).
                              5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley

                              91 Lincoln Mark VII LSC grandpa spec white and cranberry

                              1984 Lincoln Continental TurboDiesel - rolls coal

                              Originally posted by phayzer5
                              I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousers

                              Comment


                                #30
                                My experience when cars needed to be primed a few times before starting it was always the pump. Plus the 302 is suppose to be around 55-60 and you said you were getting 40 at most? Definitely the pump is giving up the ghost.

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