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Stalls when pressing gas too fast

Discussion in 'Tech Discussion' started by thecantaloupeman, Jul 25, 2019.

  1. Doppleganger

    Doppleganger Supporting Member Supporting Member

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    I sent my Rochester to Mountain Man Carb and FI in Arkansas. Took about a week and cost me something around $275 (returned postage included). Quadrajets is his forte' - look him up on the hot rod sites. This is what it looked like when it came back:

    04 After.jpg

    I'm going LS or TBI so wont use it. Was going to toss it on feebay.
     
  2. thecantaloupeman

    thecantaloupeman Full Access Member

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    Im not 100% sure if that carb would work on my truck or not because it looks like it has an electric choke, and the layout is a bit different, but how much were you thinking about selling it for?
     
  3. Doppleganger

    Doppleganger Supporting Member Supporting Member

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    I agree you should compare it to yours. Mine was a left coast truck so might have had extra emissions garbage on it also.

    I was going to toss it on feebay for $300. It even came back with new gaskets.

    Here's another pic of the backside.

    02 After.jpg
     
  4. thecantaloupeman

    thecantaloupeman Full Access Member

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    Yeah yours is electric choke and I don't think I wanna mess with that. It's also got the vacuum in the back instead of the front. I might consider having mine sent to that place in arkansas though.

    Only thing is the previous owner claims to have rebuilt it. It does look fairly clean, so I don't know if its worth almost 300 for a re-rebuild. I might just see if I can pop the top off to replace the accelerator pump. After that I might buy a quadrajet from the junkyard and then I can practice rebuilding it, then I might rebuild mine to be really nice later on.
     
  5. DoubleDingo

    DoubleDingo Vacuum Leaks, The Root Of All Evil

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    Doesn't mean he knew what he was doing or did it correctly. A properly rebuilt and adjusted q-jet will operate like a dream.
     
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  6. 4WDKC

    4WDKC Full Access Member

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    in my mind no, not sure if it will actually come apart or not but more importantly its a whole lot harder to drop a screw in the engine if the carb is not on the engine.
     
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  7. 4WDKC

    4WDKC Full Access Member

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    Im no carb guy but isnt that a computer controlled carb?
     
  8. 1987 GMC Jimmy

    1987 GMC Jimmy Automobile Hoarder

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    This should be an 85-86 carb with a dual capacity accelerator pump. The E4ME has the little plug on top for the MCS plus the TPS connector sticking out of the body on the front driver’s side of the carb.

    I second Mountain Man. That’s where I sent my E4ME, which is the feedback variant of the Quadrajet used in non-TBI, V8 powered GM cars from model years 81-90 and in California square bodies from 81-86. That’s easily the most complicated carburetor ever built so if they can do that... Mine was like $200 plus shipping, though.

    I would do this and not worry with it for a very long time. I think there are too many variables to combat with not having torn into one before, trusting the word of the PO, who can help me locally if something goes wrong, etc.
     
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  9. Nonstop

    Nonstop Full Access Member

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    Not trying to be “that guy”, but it is time to shit or get off the pot. This thread is almost a month old. Every time you drive your truck, you are putting yourself in harms way if the accelerator pump is shot. That means you cannot take certain evasive actions if needed, and unless you are constantly cognizant of what is going on, you risk stalling out constantly. This is a more important issue than say, what color should I paint my truck, or should I lower it.
     
  10. thecantaloupeman

    thecantaloupeman Full Access Member

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    I haven't driven it since I had this problem. Nor will I have to until I finish Basic Training and go to wyoming to join the Air National Guard.
     
  11. Nonstop

    Nonstop Full Access Member

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    Ah, then my hat is off to you! Might be the best time to send it out then while you are in basic.
     
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  12. thecantaloupeman

    thecantaloupeman Full Access Member

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    Actually I may not have to. I just got in touch with the owner and he says he replaced the accelerator pump. Maybe I'm doing that test wrong or something. I suppose it's possible it broke even if it's new, but it seems really unlikely.

    He said check the other fuel filter under the truck. I don't see one other than one on the right side of the truck, but that tank is bypassed. I'll send a picture, but something here looks wonky to me.

    [​IMG][​IMG][​IMG][​IMG][​IMG][​IMG]

    Sent from my SM-G950U using Tapatalk
     
  13. TravisB

    TravisB Full Access Member

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    I put a new accelerator pump in a rochester 2jet and it lasted one day.

    https://www.gmsquarebody.com/threads/69-gmc-c-15.24904/page-5#post-502772

    I drove it a couple of days with it like that. This is what it would do in the garage. Ignore that goofy dog barking but maybe you can hear what the truck is doing when I open the throttle somewhat slow versus pretty quickly.

    https://photos.google.com/photo/AF1QipOqqVvUz0milNSG0C6Aay965cPMcd0IHYpAfhCr
     
  14. thecantaloupeman

    thecantaloupeman Full Access Member

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    Your video is not showing up for me. I get a 404 error. But why do you think the pump failed so quickly? Maybe I'm having the same problem as you. Bad part maybe? Maybe the previous owner that rebuilt my carb bought the same part as you.
     
  15. TravisB

    TravisB Full Access Member

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    The first link to my thread is a picture. I took it apart again to see what went wrong and the rubber plunger came off the pump rod and was just hung in the bottom of the pump well. I wasn't sure that's what was wrong until I took it apart. The pic shows the pump and plunger as two pieces instead of one like came with the rebuild kit.

    https://photos.app.goo.gl/Yd6ALD52nNGTrsJa7
     

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