Intake plenum gaskets

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Bextreme04

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I got the carb off the truck and apart today, got the air horn off ok. I poured the gas that was in there out. The power valve with the two needles was stuck and a little bent, and the needle valve was completely off and the wire spring that holds it on the float was off. How did that happen, did I do it pouring the gas out? don't think I bent the power valve part, and I think I got it straightened out ok, but maybe the needle valve fell off when I poured the gas out? I put it back together and hung it on the float, should I get a new one? Having trouble figuring out how to check the float level. I found a really good video that is pretty helpful but this is kinda scary for me. Not sure how I'm going to get the needles on the power valve into the jets, and I don't want to try until I know if I should get a new needle valve.
Yes, needle likely fell off when you turned it over to dump the gas, it just hangs on there by the spring normally. The power valve hanger can easily get bent if the last person to assemble it didn't make sure the needles were lined up inside the jets before assembly. It's kind of a pain to get everything lined up and in the right spots in the air horn gasket while assembling it. If you slip and it slides out of the jet and moves a bit to the side, then it will jam up sideways and then get damaged when someone tries to keep bolting it down.
 

Ricko1966

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I got the carb off the truck and apart today, got the air horn off ok. I poured the gas that was in there out. The power valve with the two needles was stuck and a little bent, and the needle valve was completely off and the wire spring that holds it on the float was off. How did that happen, did I do it pouring the gas out? don't think I bent the power valve part, and I think I got it straightened out ok, but maybe the needle valve fell off when I poured the gas out? I put it back together and hung it on the float, should I get a new one? Having trouble figuring out how to check the float level. I found a really good video that is pretty helpful but this is kinda scary for me. Not sure how I'm going to get the needles on the power valve into the jets, and I don't want to try until I know if I should get a new needle valve.
I would replace the needle and seat. Get a non windowed seat. And leave the clip off that holds the needle to the float. After your non windowed seat is in fill the bowl with liquid of your choosing to just below the top of the seat. Walk away,come back later and see if there is a puddle underneath the carb. Yes? You have leaky plug wells,we can walk you through that. No puddle? Put it back together.
 
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yellowdog5

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So it runs good enough to pull a horse trailer down the highway? Seems only problem then is the priming issue?
No it used to run good enough to pull a trailer, priming has been a problem for a long time even though I had it worked on twice, then it started getting worse so I was afraid to try pulling the trailer, it was weak at low speeds and I don't know if it would have pulled a hill. I hauled 4 loads of hay 10 miles on flat ground, pretty puny uner a load and it finally quit. I installed the accelerator pump, cleaned the carb up (wasn't very dirty) and checked the float level to the best of my ability, put it back on the truck and now it starts without priming and runs pretty strong, still seems alittle rough so not sure it's perfect but it does run a lot better. I'll haul another load of hay after I change the oil today and see how it does.
 

yellowdog5

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How come 2 "mechanics", one in a shop, couldn't figure out it needed an accelerator pump? I know for a fact the first one used the old one because a new one didn't come with the kit. Just venting here, I have a lot more questions about the truck since I am using it quite a bit now, but will save them hopefully until I get all the hay hauled. A big thank you to everyone that helped.
 
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DoubleDingo

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How come 2 "mechanics", one in a shop, couldn't figure out it neede an accelerator pump? I know for a fact the first one used the old one because a new one didn't come with the kit. Just venting here, I have a lot more questions about the truck since I am using it quite a bit now, but will save them hopefully until I get all the hay hauled. A big thank you to everyone that helped.
Sadly that is the way a lot of "mechanics" are nowadays. Integrity is no longer a trait the majority possess.
 

Grit dog

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How come 2 "mechanics", one in a shop, couldn't figure out it needed an accelerator pump? I know for a fact the first one used the old one because a new one didn't come with the kit. Just venting here, I have a lot more questions about the truck since I am using it quite a bit now, but will save them hopefully until I get all the hay hauled. A big thank you to everyone that helped.
Because many of us here aren’t even mechanics by trade but are mechanically inclined. Helps that everyone here has some connection to 70s-80s GM vehicles. And at some point I bet all of us got hornsshwaggled by a “mechanic.” And like you either out of necessity or frustration said “fck it. I’ll do it myself!”

Glad to hear it’s running better.
 

yellowdog5

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I hauled hay this morning, started up with 3-4 pumps. It runs ok but seems rough, sometimes hesitates when taking off. I know this doesn't explain much but I think it still needs help, not sure where to go from here.
 
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DoubleDingo

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How's the timing?
 

yellowdog5

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How's the timing?
The guy that looked at it recently checked it and was happy with it, I need to learn how to check it myself, something I have never done. I just looked at a video of it, I need to see if my timing light is a good one or a cheap one, hopefully it will work. Edit: My timing light is Innova 3551, it's pretty old but last I knew it worked fine (not used by me, by my late husband and his father).
 
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DoubleDingo

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The guy that looked at it recently checked it and was happy with it, I need to learn how to check it myself, something I have never done. I just looked at a video of it, I need to see if my timing light is a good one or a cheap one, hopefully it will work. Edit: My timing light is Innova 3551, it's pretty old but last I knew it worked fine (not used by me, by my late husband and his father).
I personally am not familiar with that brand of timing light, but I am sure it's more then capable to check it and set it.
 

yellowdog5

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I personally am not familiar with that brand of timing light, but I am sure it's more then capable to check it and set it.
Okay now I just need to learn how. Hope I can see well enough to see the marks.
 

DoubleDingo

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If you have the oem air cleaner housing, follow the instructions on the label.

On mine, if I time it like I learned to, it'll be off. On mine, it needs to be up to operating temperature, all carb adjustments done, rpm set, and everything hooked up like you would drive it. Then I can set the timing. It goes against everything I learned and what people say to do. I say this so you can follow the correct procedure, granted it has the sticker on the air cleaner
 

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