New '82 SR5 Vacuum issues

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Hey guys, just picked up a 1982 SR5 from my neighbor whom I've been bugging for the better half of two years to sell it. Hadn't asked for months then I got the call; "get it out of my driveway!"

Anyway, it was sitting for 4+ years but overall is a really solid truck. Frame is in great shape. Been working on it and have it running to a point where it's "driveable" but still runs rough. I rebuilt the carb and went though the vast majority of it but I'm stumped as to how to proceed.

There was a huge vacuum leak in the carb between the plate and manifold that I think I fixed. It idles ok (not perfect) at this point, but I still think there is another leak. When driving it, anything from about 40-95% throttle it's stumbles all over and feels like 2-3 cylinders. Full throttle will keep it running, although a little bit is present depending on rpm. I can pump the gas quickly and that will help keep it accelerating.

What I'm stumped with is trying to find this leak (if that's what it is)

I've tried the propane/map gas trick and tried blowing cigar smoke into the manifold through the brake booster hose. Inspected all the hoses and while old, none look cracked. Not sure what else to try.

Thoughts?

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Have you adjusted the carb after rebuilding it?
 
Gorgeous truck... I miss my 79 & 83 everytime I see that gen pickup. New manifold gasket? What about the doughnut gasket(s) at the bottom of the manifold? Both my trucks (20r & 22r) had leaky exhaust manifolds when I first got them running.
 
Thanks! I love the paint colors. Eventually I plan on repainting it with the same scheme/colors. Thinking I'm going to have to have the vinyl accents done custom though, can't find them anywhere.

As far as the engine; wires, cap, rotor, plugs, fuel filter all replaced, carb was set to what is apparently recommended as factory, idle is 3.5 turns out and fuel is 2.5 turns out.

I have not replaced the manifold gasket and I was not aware there were doughnut gaskets under the intake manifold. I was putting a propane in that area at idle and didn't notice anything. Currently the truck starts and idles fine, it's just under load where it runs like poop.
 
warped float bowl. 2nd and 3rd piece of the carb won't seal. Spent 4 hours trying to flatten it out, no dice. Ordered a new carb.
 
I recommend giving up and donating the truck to the closest 22r person in your general vicinity! :idea:
 
New carb did wonders. Runs like a champ! No donations just yet...
 
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