studder problems HELP

Discussion in 'Technical' started by Rob C, Dec 15, 2003.

  1. Rob C

    Rob C Member

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    ok heres the story... tanks got some rust like most 30+yr old cars so i switched out fuel filters again. cept this time i put an inline fuel filter before the fuel pump.i then took the car to the shop they reset my points and timing and replaced the gaskets betweent carb/spacer and spacer/manifold. so now it running good until today i noticed that when i hit 45-50mph it starts to buck and it sounds like the motor is about to die but it doesnt stall out. its fine from a stand still and backroad driving but main roads and highways are crap.

    could i have clogged filters again? could the filter that is before the fuel pump be starving the motor of fuel? its a cheap see through filter from pepboys. i figured that if i started to suck rust again i could see it this way. maybe did i install it wrong? im sure the flow direction is the right way but do you have to fill it with fuel or something before installation?
    if that isnt it then tell me what it is please!
    ANY INPUT IS GREATLY APPRECIATED!
    thanks,
    rob

    sorry for the long post guys
     
  2. Bluegrass

    Bluegrass Jr. mbr. not really,

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    A fuel pump can act this way. At engine speeds under a certian level, the pump keeps up with supply. Out on the highway at higher 'sustained' speeds the pump can't keep up the supply and fuel runs low in the carb.
     
  3. Country Mav

    Country Mav Die-Hard Ford Guy!

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    My pump can't keep up

    It does good until I run it, and then sit and idle, the fuel filter will run completely dry. I haven't noticed it wanting to die, but I know that it would run better if I had a better flow rated pump. One day..........Country
     
  4. Mavaholic

    Mavaholic Growing older but not up!

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    Another thing to check is the rubber hose back at the tank and under the car (if there is one). If it has those spring type clamps, trash them and put some new screw clamps on there with a new piece of hose. I had a Bronco that would intermittentlt suck air through that spring type of clamp. Drove me nuts for a month before I finally found it.
     
  5. Grabber75

    Grabber75 Member

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    i have the see thru filter on my truck.....the one you can take apart and clean the element right?.....i have noticed that it runs dry on it too but have never had a problem with it so i dont think its your filter
     
  6. Rob C

    Rob C Member

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    my bet it is prob. the carb. now should i just replace it? and would local shops like napa pepboys or abc auto carry and or be able to get it?

    if i were to take it off and clean it up nice where do i start and what am i looking for (bowl)
    just give me an idiots guide if you dont mind!!! please:p
    im only 17 and pretty much everything i do its my first time so give me some instructions!

    thanks for the input guys!
     
  7. Dan Starnes

    Dan Starnes Original owner

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    Rob, a lot of good advice has been posted above. I would take the carb off after exhausting all other possible problems. It could be as simple as a rubber portion of you fuel line collapsing. Pretty cheap to fix but sometimes hard to find. If you have not replaced all the rubber segments of your fuel line, tank to carb, it would be a good idea and then would rule that out. This is a part of troubleshooting which is time consuming but mandatory when working on old cars. Also, have you thought of rebuiding the carb? Instructions on how to do are included with the kit you buy. Not real hard to do, but it is very important to get the carb clean when doing this, and I mean parts washer clean. Not carb spray clean.
    Dan
     
  8. 71gold

    71gold Frank Cooper Supporting Member

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    rob, another check i would do is to see if the vent line on the tank is not stopped up.it is the one that goes to the little canister under the hood. it is on the pass. side next to the heater hose connections at the firewall...frank...:bananaman :bananaman
     
  9. Rob C

    Rob C Member

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    alright well i did replace all the rubber fuel lines under the hood. including the metal line that goes from the pump to the next section of rubber. where is the rest of the rubber lines located? i guess what im trying to say is where does it start a point of reference would help.

    i would drop the tank out because i know that needs to be cleaned and recoated but currently i have no area to do that kind of work. im moving to a nice house in jan. ill get that job done then.

    about the carb rebuild kits do you happen to know where i could get one? would the local chains carry them or would i have to order from a specialty place?

    thanks for all the info guys i know im a pain in the @$$:D
     
  10. 71gold

    71gold Frank Cooper Supporting Member

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    :rolleyes: rob, you might want to pull the sending unit and check the sock.( fillter) on the end of the pickup tube...frank...:bananaman :bananaman
     
  11. Rob C

    Rob C Member

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    AHHH good thinking with the sending unit cuz mine has crapped out according to the mechanic. he said i needed a new one. if i were going to replace it do i have to drop the tank out? any pointers would be great. hehe thanks again:rolleyes:
     
  12. 71gold

    71gold Frank Cooper Supporting Member

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    :D two points. first you don't have to pull the tank to get it out. it has a big ring nut with ears to tap on to undo. be careful with the o ring. second. why does he think it has crapped out?...frank...:bananaman :bananaman
     
  13. Mavaholic

    Mavaholic Growing older but not up!

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    Try to run the tank as dry as possible before you pull the sending unit. That creates 1 big hole for gas to dump out of.
     
  14. Rob C

    Rob C Member

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    i get no reading at all from the gas tank. he checked it out and said that it needed to be replaced but he couldnt get the part. and besides it cant hurt to be replaced right?

    where on the tank is it?

    hehe lack of experience sucks and bad weather sucks cuz i cant go out there and figure it out myself!:rolleyes:
     
  15. 71gold

    71gold Frank Cooper Supporting Member

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    :rolleyes: good point dennis. the unit is behind the driver side rear wheel. you don't have to take the wheel off but it is easier to get to if you do....frank...:bananaman :bananaman
     

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