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Dana02
05-31-2022, 06:03 PM
Hey guys,
So I did a full black box delete along with other mods to the carburetor following the guide in this group. I got the car running great after fighting with a spark issue, wire ends were not Into the end of plug wires fully. I drove probably 100 miles since i finished everything but I noticed the jet for the first bowl doesn't squirt any fuel, it stays dry and I can't figure out why. I rebuilt the carb twice now and doubled checked everything. I searched everywhere on the forum and nothing close to my issue. Could any one help out? Thank you in advance

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ShiRen
05-31-2022, 06:55 PM
Which one are you calling the first one? Where are you looking for fuel to squirt out? If you were not getting fuel out of the primary venturi, then it straight up wouldnt run, If you were not getting fuel out of the accel pump nozzle you would bog really hard when you jab the throttle, but I could definitely see it being out of adjustment or broken. If you were not getting fuel out of the secondary venturi then it would fall flat on its face at 50% throttle and go super lean. All of the above are extremely noticeable and would not be what I call "running great"

Oldblueaccord
05-31-2022, 07:36 PM
Hey guys,
So I did a full black box delete along with other mods to the carburetor following the guide in this group. I got the car running great after fighting with a spark issue, wire ends were not Into the end of plug wires fully. I drove probably 100 miles since i finished everything but I noticed the jet for the first bowl doesn't squirt any fuel, it stays dry and I can't figure out why. I rebuilt the carb twice now and doubled checked everything. I searched everywhere on the forum and nothing close to my issue. Could any one help out? Thank you in advance

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Does it only have a accelerator pump on the first stage? Just guessing.

ShiRen
06-01-2022, 04:43 AM
Does it only have a accelerator pump on the first stage? Just guessing.

Yes, you usually dont jab the throttle hard enough that the accel pump squirt overlaps the secondaries opening, at least this was the case with the stock vacuum secondaries.

Dana02
06-01-2022, 02:22 PM
Yes, you usually dont jab the throttle hard enough that the accel pump squirt overlaps the secondaries opening, at least this was the case with the stock vacuum secondaries.Would the accel pump coming on before secondary cause it to not spray in the secondary? Looking at the front of the car, is the secondary the first barrel or second barrel ?

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ShiRen
06-02-2022, 05:27 AM
The secondary is the barrel closest to the front of the car, it doesnt even open until half throttle, assuming you converted to a mechanical secondary. Accel pump sprays in the primary. You can see it spray gas from the back side of the carb from a tiny hole into the primary whenever you crack the throttle, it only squirts momentary.
So if you arent seeing the secondary spray gas you either arent opening the throttle enough or you didnt do the mechanical secondary mod, which is required without the black box. If you open it WOT and you never see the throttle blade open then you didnt do it correctly, the car will also be really slow, but probably runs fine.

Dana02
06-02-2022, 07:38 AM
The secondary is the barrel closest to the front of the car, it doesnt even open until half throttle, assuming you converted to a mechanical secondary. Accel pump sprays in the primary. You can see it spray gas from the back side of the carb from a tiny hole into the primary whenever you crack the throttle, it only squirts momentary.
So if you arent seeing the secondary spray gas you either arent opening the throttle enough or you didnt do the mechanical secondary mod, which is required without the black box. If you open it WOT and you never see the throttle blade open then you didnt do it correctly, the car will also be really slow, but probably runs fine.I did the secondary mechanical mod but I swear it doesn't spray any fuel out. It might be me, I'm not sure. I don't have a way to record the barrel opening or closing right now while driving. I was wondering if the secondary fuel supply is messing up. Is there a way for that?

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ShiRen
06-02-2022, 09:54 AM
As long as you know it is physically opening, if there was not any fuel and you floored it it would fall flat on its face. If it revs fine then I think you are worrying about nothing. It should have a little studder when you pass half throttle, the faster you give it throttle the more pronounced it will be, simply because the carb cant compensate for the large ramp in air volume as the secondary opens, as more air goes through the secondary it pulls fuel out of the venturi, if it didnt pull fuel out you would technically have a giant vacuum leak

Dana02
06-02-2022, 12:52 PM
As long as you know it is physically opening, if there was not any fuel and you floored it it would fall flat on its face. If it revs fine then I think you are worrying about nothing. It should have a little studder when you pass half throttle, the faster you give it throttle the more pronounced it will be, simply because the carb cant compensate for the large ramp in air volume as the secondary opens, as more air goes through the secondary it pulls fuel out of the venturi, if it didnt pull fuel out you would technically have a giant vacuum leak Okay thank you I might be over thinking it then. Lol I should probably double check vacuum lines and gaskets just to be safe.

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ShiRen
06-03-2022, 04:47 AM
If you did the vacuum delete you shouldnt have more than like 2 lines right? Yes, you should use some new hose though. Only gasket that should matter is the carb base gasket.