Fuel - '82 EXP Loses Fuel Pressure | Page 2 | Ford Escort Owners Association (FEOA)
  1. Wash your hands and do not touch your face, keep it safe and clean. Long live Feoa!

Fuel '82 EXP Loses Fuel Pressure

Discussion in '1st Gen 1981-1990 CVH' started by rob289c, May 18, 2018.

  1. denisond3

    denisond3 Moderator Staff Member

    Messages:
    10,158
    Likes Received:
    2,850
    Trophy Points:
    563
    Location:
    south TX or northern VA
    I personally would not rule out carb problems. Back in those days (82 & later) the automakers were facing more stringent emissions, and one result was carburetor complexity. The manufacturers complained that fuel with ethanol in it was hard on some of the internal non-metallic parts of carburetors; like the plastic tips on the electrically controlled valves, the one for the idle cutoff, and the one for the float vent. This was enough of a problem with the Mikuni carb on my 87 Dodge minivan, that the vehicle got its first replacement carb while still under makers warranty, and was on its 3rd replacement professionally rebuilt carb (nationalcarburetors(dot)com) as of two years ago - when I gave up chasing problems. Now that vehicle is just my lockable tool-box.
    The idle circuit fuel shutoff is likely a solenoid driven valve, that shuts off fuel when the ignition is off - so the engine doesnt keep doing what was called 'dieseling', i.e. not shutting off, but coughing and stumbling briefly.
    With my minivan, I could always get it to start by dribbling a little fuel into the carb (either throat), but it would only run till that much fuel was used. Sometimes I could get it to work by rapping the body of the carb with a ballpeen hammer. There wasnt any good way to tell if the fuel cutoff valve was opening up again, or if the other two electrically controlled valves were working; the float bowl vent valve, and a fuel metering valve.
    zzyzzx likes this.
  2. rob289c

    rob289c FEOA Member

    Messages:
    32
    Likes Received:
    11
    Trophy Points:
    8
    Ah, ok...thanks. I figured it would only affect the idle circuit but thought I'd ask anyway. When I saw "fuel shutoff solenoid", I thought I should get more info. I will get this figured out one way or another!
  3. 88ESCORTV6

    88ESCORTV6 The Alpha Of The Omega

    Messages:
    1,282
    Likes Received:
    267
    Trophy Points:
    333
    Location:
    Hawkesbury Ontario
    I have a good carb but it's not for sale.......But.... where do you live?
    zzyzzx likes this.
  4. rob289c

    rob289c FEOA Member

    Messages:
    32
    Likes Received:
    11
    Trophy Points:
    8
    I live in Ontario.....Ontario NY. Just east of Rochester. I see you're between Ottawa and Montreal. I bet you're not even watching the Stanley Cup! I have another carb...don't know the condition and probably never rebuilt. It sits on a spare intake/head assy I have in the garage. I may have that one rebuilt and do a quick swap to see if that changes anything.
  5. rob289c

    rob289c FEOA Member

    Messages:
    32
    Likes Received:
    11
    Trophy Points:
    8
    After more reading and You Tube videos, I am going to go down the vapor lock trail. JOEG5982 suggested that as a possibility earlier on in this thread. Several videos described the symptoms that I am having with a variety of potential repairs: carb spacer, heat shields, fuel line insulation, electric fuel pump to name a few. I am going to start by finding some clear fuel hose and install on the supply line with a pressure gauge. The clear hose will let me see if I have a strong flow or if it starts to bubble and vaporize. The gauge will confirm. Once I see it with my own two eyes I can try some remedies to try to solve my problem.

    Has anyone insulated their fuel lines and with what? How about conversion to electric fuel pump? What did you do about the return line and blocking off where the mechanical pump goes? Did you use an oil pressure interlock switch to prevent the pump from running without the engine running? Any other vapor lock stories to share that will give me more/better ideas? Would changing the thermostat to a lower temp rated one help?

    Thanks again for all the suggestions.

    Rob
  6. denisond3

    denisond3 Moderator Staff Member

    Messages:
    10,158
    Likes Received:
    2,850
    Trophy Points:
    563
    Location:
    south TX or northern VA
    I installed an electric fuel pump on a Fiat. It was just wired to one of the accessory lines, like the radio was.
    I would examine the routing of the fuel lines, to make sure they were not "in-sight-of" or close to the exhaust parts. If so, some aluminum wrapped around either the fuel lines, or to shield the exhaust parts might help. Heat shields on exhaust systems rust away pretty easily. On my 2nd gen Escorts, the original cat converters all had 4 heat shields originally. Most of them are now missing.
    zzyzzx likes this.
  7. zzyzzx

    zzyzzx FEOA Member

    Messages:
    15,209
    Likes Received:
    1,231
    Trophy Points:
    463
    Location:
    Baltimore, MD USA
    One of the reasons I bought a GT in January of 1985 is because my previous car had a carburetor, and you had to go to the GT trim level to get fuel injection. It could still be the carb. I don't care who rebuilt it, there isn't anyone or maybe hardly anyone left who actually knows how to rebuild them, and they work like crap even when new, and are really hard to get them to work right, even with an electronic choke (which is the only way to go, but still sucky). Verifying the fuel pressure is a good start, and going electric with that would probably be an improvement over a mechanical pump.

    Other than the electronic choke, I have never heard of needing electricity for a carb.

    If you don't already have it, get AAA+
    denisond3 likes this.
  8. denisond3

    denisond3 Moderator Staff Member

    Messages:
    10,158
    Likes Received:
    2,850
    Trophy Points:
    563
    Location:
    south TX or northern VA
    The carb on my 87 Dodge minivan has three connectors to the three solenoids inside it. I think there must be a demon or a bad elf inside the late model carburetors.
  9. Joey_Twowagons

    Joey_Twowagons FEOA Member

    Messages:
    2,531
    Likes Received:
    1,189
    Trophy Points:
    413
    Location:
    Vancouver Island, Canada
    While the later carburetors were saddled with numerous add ons that made them complex and prone to trouble, it is unfair to say that carburetors fundamentally "work like crap when new" etc.

    A simple carburetor can work quite well, although not as efficiently as fuel injection.
  10. rob289c

    rob289c FEOA Member

    Messages:
    32
    Likes Received:
    11
    Trophy Points:
    8
    Thanks for the continued feedback. I like all the knowledge we bring each other. The carb on the '82 EXP has the idle circuit fuel shutoff solenoid, and at least one or two other electric actuated solenoids. I don't believe any of them are my culprit. As for all carbs sucking, the Autolite 2100 on my '67 Mustang performs beautifully. The choke works, it runs smoothly, and literally no hesitation. Yes, FI is more precise but I'm trying to work with what I've got. Fuel line routing: The factory plumbing consists of rubber off the tank to rigid steel lines under the car and up the right side firewall into the engine compartment, then back to rubber, then steel lines on the intake side of the head to the fuel pump, then the return follows the same path in reverse back to the tank. The fuel lines are on the opposite side of the head from the exhaust. I could completely modify the underhood routing to keep the lines further away from the engine. I will look to see what that would take. Keep the ideas coming and I will report back as I make progress.
  11. Joey_Twowagons

    Joey_Twowagons FEOA Member

    Messages:
    2,531
    Likes Received:
    1,189
    Trophy Points:
    413
    Location:
    Vancouver Island, Canada
    Is it crazy hot where you are now? If not, I don't see the vapour lock theory being likely.
    What is really needed is diagnosis. If you had a pressure gauge in the line you could see if there were fuel pressure when the fault occurred.

    Another test you can do is bring along a bottle, and when the car stalls, pull the hose off of the carb and direct it into the bottle. If fuel gushes out when cranking, you know it is not a fuel delivery problem.
    You might need to bring along a longer hose to do this test, or even install a tee with a hose and shutoff valve for diagnostic purposes.

    But plumbing in a pressure gauge (0-10 psi or so) that is visible while driving will be most informative. I believe most vacuum gauges have this low pressure scale on their face, specifically to test mechanical fuel pumps.
    denisond3 likes this.
  12. rob289c

    rob289c FEOA Member

    Messages:
    32
    Likes Received:
    11
    Trophy Points:
    8
    My vacuum gauge will test fuel pressure so I will be doing that this weekend. It's not crazy hot but it does get hot under the hood. The shroud over the exhaust manifold is missing but I don't know if that makes a lot of difference in underhood temps. Something I thought of earlier is the stock cooling system incorporated a rigid tube on each side that went under the engine and are the supply and return to the heater core. The one on the left side incorporated a tapping that feeds coolant via a 3/8" hose to the underside of the intake manifold. Both tubes were corroded and leaking when I got the car so rather than go under the car, I routed 1" heater hoses around each side, then fabbed a 1" x 1" x 3/4" black iron tee with 1" hose barbs on the runs of the tee and a 3/4 x 3/8 bushing and 3/8 hose barb on the leg of the tee to feed coolant to the intake. The temp gauge runs way cool as the cooling system is all new with a new radiator, water pump, heater core, hoses, thermostat. I wonder if that 3/8" line to the bottom of the intake has anything to do with vapor lock...IF vapor lock is my issue. I will do some testing over the weekend and report. If I think of anything else I will post.
    Pyoro and denisond3 like this.
  13. rob289c

    rob289c FEOA Member

    Messages:
    32
    Likes Received:
    11
    Trophy Points:
    8
    Here's my update: This morning I swapped the black supply and return fuel hoses that connect the rigid line that come up from under the car to the fuel rail that runs parallel to the back side of the head on the intake side to blue, transparent hoses. I wanted to see if I had a steady stream of fuel to the carb while running and also when it went into its failure mode. After changing to the transparent hose I started the car and observed a fairly full hose, although there was an a bubble at the apex of the supply hose. The return hose wasn't a steady stream and had quite a few bubbles. I took it for a test drive. The weather was clear, not quite 70 deg and low humidity. I drove to the next town over which is about 9 miles away. The outbound trip was on a rural highway and I drove 50-55 mph. On the return trip I traveled a 55 mph divided highway. At about the 14 mile point of the trip I decided to take it up to 65 mph. It began stumbling and felt like it was losing fuel pressure. I let off on the throttle as I wanted to make it home and had about 5 more miles to go. I made it home and parked in the garage. I took a peek at the hoses before shutting down and there was only a very little fuel visible in the line. I went inside and ate lunch to simulate shopping at Lowes which is where it left ma stranded the last two times. I left the hood down so if underhood heat is an issue I didn't want to alter anything by leaving it up and letting the heat dissipate. After lunch I went out and just like at Lowes, it fired right up. I simulated driving in the parking lot by idling about 2000 rpm. Sure enough, it ran itself out of fuel and died. I tried to re-start it once and it did not. There was no visible fuel in either the supply or return hoses. I left the hood up to see if cooling down would make a difference and after about 45 minutes I saw there was fuel in the supply hose. Not a lot, but there had been none after it died. I gave it a shot of ether as that's what I had done in the past when it died and it popped off and ran. I manually operated the throttle under the hood and held it a fairly high rpm and observed the hoses. It went from fairly full flow to very little flow, then as it got hotter under the hood it eventually stumbled, the fuel hoses were empty and it died. I should add that the fuel lines were not hot to the touch, the carb body was not hot, the fuel pump at the top wasn't hot, and the carb spacer wasn't hot. The intake manifold was hot and the bottom of the fuel pump where it bolts to the engine was hot. The next step was to tie in a fuel pressure gauge, test drive it and see what happened with the gauge during different operating conditions. I will report on that in a little while. I have to go help my son get the cover off the pool.

    Attached Files:

  14. rob289c

    rob289c FEOA Member

    Messages:
    32
    Likes Received:
    11
    Trophy Points:
    8
    The rest of the story is going to be later or tomorrow. Have to go out with the wife...
  15. rob289c

    rob289c FEOA Member

    Messages:
    32
    Likes Received:
    11
    Trophy Points:
    8
    OK, I'm back. So I rigged up a contraption so I could tie in my vacuum/fuel pressure gauge to see what kind of pressure the mechanical fuel pump was putting out. I ran the fuel hose though the hood vents and put the gauge under the wiper so I could see it while driving. I did about a 15 mile drive. Fuel pressure started out between 6.5 and 7, then settled out around 6.25. The car ran fine until I got on it a bit at around mile 9. It would stumble when I got the rpm's up. The fuel pressure stayed up over 6 psi even when stumbling. I didn't let it stumble long; I wanted to get home. The operating temp was staying down at the low end of the normal scale. I got it home, left it running, and manually held the throttle open to see what would happen. Eventually the fuel hoses had little to no fuel running through them but the pressure stayed up. When the engine began to stumble, the pressure started going down and when the engine quit fuel pressure was at 4 psi. After a few minutes the pressure dropped to 0 psi. I spent about an hour cleaning the garage and sweeping and when I looked at the fuel hose it had fuel in it again. I was able to start the car and drive it into the garage. I just looked at it when I got home and the supply hose is full of fuel.

    So, after all that, what do you think? I think installing an electric fuel pump back by the tank will be my next project. I'm thinking an Airtex E8012, 12v 5-9 psi, with the OS75 oil pressure safety switch. I think pushing the fuel from the tank to the carb will work better than the mechanical pump trying to suck it to the carb. I would think a full flow through the fuel hose is what I should see. I don't know why the flow goes down to a trickle after running for a few miles. Has anyone installed an electric fuel pump like I am proposing? Anything I need to be aware of? Do I need a fuel pressure regulator? The factory manual says the stock mechanical pump should put out 4.5 - 6.5 psi with the return plugged. I didn't plug the return. Maybe tomorrow.

    So what is the concensus? Bad carb, bad fuel pump, vapor lock? I need to get this figured out so I can enjoy this car. Any opinions will be appreciated.

    Rob

    Attached Files:

  16. 88ESCORTV6

    88ESCORTV6 The Alpha Of The Omega

    Messages:
    1,282
    Likes Received:
    267
    Trophy Points:
    333
    Location:
    Hawkesbury Ontario
    maybe you have,
    Cracked fuel line-hose
    back pick-up tube in tank.
    can you try a inline fuel pump at place of mechanical fuel pump?
    heat from engine block-cylinder head making fuel boil in mechanical fuel pump creating vapor lock, do you have a plastic spacer?
  17. rob289c

    rob289c FEOA Member

    Messages:
    32
    Likes Received:
    11
    Trophy Points:
    8
    The rigid fuel lines under the car and under the hood are solid. All the hoses were replaced and clamped during the restoration. The filter at the end of the pickup was cleaned with carb cleaner prior to installing in the brand new tank. The plastic spacer between the intake and carb is in place and not hot to the touch, while the intake is very hot so it is doing its job. The top of the mechanical fuel pump above the diaphragm where the fuel is is not hot to the touch, however, the bottom of the pump where it bolts to the engine and all the mechanical action takes place is hot.

    I have a spare head with carb so I could cannibalize the spacer and double it up to raise the carb another 1/4" but I don't think that is the issue. I would have to replace the carb studs with longer ones. Not a big deal but not going to do this unless other remedies don't work.

    There is a possibility that when I installed the tank I crushed the supply hose between the top of the tank and the floor of the car. I am planning to get it on jackstands today to scop out where I am going to install an in line electric fuel pump so I will see if I can determine if a hose is flattened while under there. I bought some fuel line insulating sleeve that I will install over the underhood lines during the fuel pump installation. Supposed to reflect 500 deg of heat. The fuel lines are not hot to the touch so I don't think that's going to solve the problem. I am banking on the electric fuel pump being able to overcome any current flow or heat issues. Unless someone has strong opinions against the pump replacement, I am going to order the pump and oil pressure switch later today.
    I have no history with this car. I bought it in 2015 as a father/son project that became a father project. Over three summers I went through it mechanically and then did body and paint. Past ownership is sketchy so I have no good history on it. It had been sitting for quite a few years and very solid with only 44k on the odometer. Maybe this issue is what caused it to sit?

    I am going to get this thing to be dependable. It's a cool little car and I want to enjoy it rather than always worrying if it's going to leave me stranded.
    Pyoro likes this.
  18. rob289c

    rob289c FEOA Member

    Messages:
    32
    Likes Received:
    11
    Trophy Points:
    8
    I ordered my electric fuel pump and oil pressure safety switch a few minutes ago. I have the car on jackstands and scoped out where I can mount the pump and how I will run the line. I sprayed the oil pressure switch with penetrating oil and will do so again a few more times this week so hopefully if will come out easily so I can install the safety switch in a tee in the same port as the oil pressure switch, unless someone is aware of another unused oil pressure port on the 1.6 engine. I hope the switch arrives before the weekend. I'll keep everyone posted.
    Pyoro and denisond3 like this.
  19. 88ESCORTV6

    88ESCORTV6 The Alpha Of The Omega

    Messages:
    1,282
    Likes Received:
    267
    Trophy Points:
    333
    Location:
    Hawkesbury Ontario
    your going to make a safety switch on the electric fuel pump? wow that is grand of you I give honor points for things like this.

    a few companies use this system and it work fine if a car is over on roof pump stops if no oil pressure pump stops so if you turn key off after few seconds pump will stop ....don't forget a fuse.

    my hat off to you.
    denisond3 likes this.
  20. Joey_Twowagons

    Joey_Twowagons FEOA Member

    Messages:
    2,531
    Likes Received:
    1,189
    Trophy Points:
    413
    Location:
    Vancouver Island, Canada
    Good testing so far.
    Mechanical fuel pumps work really well in millions of cars, so there is definately something wrong in the fuel system, rather than a design flaw.

    One more test I would do is to tee in the vacuum gauge just before the fuel pump, to see if there is a clog in the line between the pump and tank. A small bit of debris could have gotten in the line at some point and be clogging the line as it moves around, say into an elbow where it lodges. Insects for example will often put junk into open tubes.

    My experience with an electric pump in a carburetted car is that it was noisy and not as reliable as mechanical ones, and more unpleasant to get at when it failed on the highway on the coldest day of winter.
    denisond3 likes this.

Share This Page