CK5
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77 Sub, my Qjet finally took a dump, so I ordered a rebuilt thru reputable mfg. 3 rebuilt units later & still junk. Got Holley, can’t get running ?

"throttle body was too worn out till after I reinstalled-thus big vacuum leak" Unless it wasnt rebuilt right I dont see how this could cause a big vacuum leak. Leaving one of the big vacuum lines open will cause a big leak. Assume you have verified every vacuum port is connected or capped and the lines connected to it arent cracked somewhere along their routes.

You said it constantly floods. I know this is a dumb question but if its an electric choke carb, do you have the wire connected? Have you verified the choke butterfly is properly/fully opening after a minute or two with just ignition power applied?
The Qjet s were flooding issue, not Holley which I have converted into electric choke. Ya dummie me forget to put fuse in , then it dawned on me next day ! Swear I used to have no problems with this stuff, now I can’t remember were I just put wrench down.
 
If the bowls are full and it started with the Holley on it I really don’t think it’s a fuel/carb issue. Look down in the carb and see if it sprays fuel when you open the throttle if so I think you need to look elsewhere….did you do the other work (plugs, wires etc) when the carb was off? If so are you sure the plug wires are on in order….did you remove the distributor?
 
Flooding could be as simple a thing as a float set too high or missing check ball. Qjets aren't as simple as a double pumper to work on but also not that much harder. They take a lot of heat but are good carbs if adjusted properly.
 
If the bowls are full and it started with the Holley on it I really don’t think it’s a fuel/carb issue. Look down in the carb and see if it sprays fuel when you open the throttle if so I think you need to look elsewhere….did you do the other work (plugs, wires etc) when the carb was off? If so are you sure the plug wires are on in order….did you remove the distributor?
Yes fuel spray is normal, when opening throttle, I have double & triple checked plug wires-there good. No I didn’t remove distributor , just changed cap.etc.With Qjet on.I just checked distributor hold down nut & it’s moving . Know I remember a guy came over to help me & I remember him loosening it to check timing. It was set 8btc, that maybe an issue also.
 
@MrHappy please reread this entire thread and answer specific questions.

How do you know you have 6 psi of fuel pressure?

If your mechanical fuel pump is a stock type pump (vs a high pressure, high $$ performance pump) why install a regulator?
I don’t know for a fact that I have 6psi pressure,just going by what Holley Tech told me gauge is pre-set at. He said carb. requires 6psi & my mechanical fuel pump is putting out 7-9 psi. Only reason for running a regulator. First gauge I put on didn’t work, haven’t put on 2nd gauge.
 
Take all the spark plugs out, disconnect the power wire at distributor coil. Crank the engine. If fuel sprays out, your engine was flooded and possibly hydro-locked. A new set of spark plug is recommended if indeed is flooded that badly.
Is just hunch that the cylinders are full of liquid gas, since several mentions of battery charging.
My qjet is running fine at 6.5 psi (engine running). A stock replacement mechanical fuel pump, for a 77 should be fine for your needs. Stock pump will have 3 ports 1, 3/8" threaded tube in, 1 out, and 1/4" push on nipple for return to tank.
How are you measuring your fuel pressure? T'ed in while running, or disconnected at carb with gauge dead headed ?
 
1) I would not trust "preset" settings, I would get a gauge and verify. Autozone rents fuel pressure gauge kits basically for free BUT with a mechanical pump I doubt you have too much pressure. You mentioned flooding - define this, was fuel pushing out of the vent tube(s).

2) With 4 carb attempts having a similar no start issues, I don't think it's a true carb problem.

3) Why did you have to charge a new battery?

4) Has this engine ever consistently run or is this a first start?

5) Is there any backfiring through the carb when trying to start it (with any of the carbs)?
 
Take all the spark plugs out, disconnect the power wire at distributor coil. Crank the engine. If fuel sprays out, your engine was flooded and possibly hydro-locked. A new set of spark plug is recommended if indeed is flooded that badly.
Is just hunch that the cylinders are full of liquid gas, since several mentions of battery charging.
My qjet is running fine at 6.5 psi (engine running). A stock replacement mechanical fuel pump, for a 77 should be fine for your needs. Stock pump will have 3 ports 1, 3/8" threaded tube in, 1 out, and 1/4" push on nipple for return to tank.
How are you measuring your fuel pressure? T'ed in while running, or disconnected at carb with gauge dead headed ?
Don’t have Qjet anymore, got Holley, adjusted distributor cap to face #1 cylinder & low NDOT behold he fired up !!
 
"It started &ran 10 seconds & hasn’t run since." Was it a smooth idle or sputtering? Was idle speed normal, fast or barely running? Did it just shut-off, like turning off the key, or sputter and die, like running out of fuel? May give a clue if its fuel system or electrical.

Just so I have it clear, your Sub was running fine then one day wouldnt start. Since then you have replaced the carb 3-times, cap, rotor, plugs, wires, had someone check the timing which was set at 8BTC (assume with engine running) and now the cap/rotor is loose? Did you reverify your timing is set correctly?
 
1) I would not trust "preset" settings, I would get a gauge and verify. Autozone rents fuel pressure gauge kits basically for free BUT with a mechanical pump I doubt you have too much pressure. You mentioned flooding - define this, was fuel pushing out of the vent tube(s).

2) With 4 carb attempts having a similar no start issues, I don't think it's a true carb problem.

3) Why did you have to charge a new battery?

4) Has this engine ever consistently run or is this a first start?

5) Is there any backfiring through the carb when trying to start it (with any of the carbs)?
Yes pre-set isn’t precise from Tiawan or ?? Flooding yes it was coming out bowl vent tube & accelerator rod. 2. I got it started & running by adjusting ignition timing , it was retarded too far . 3. I over cranked engine & drained battery. 4. I’ve had this engine in burb for 60-70k miles. 5. Carb. 2&3 almost caught engine etc. on fire . What I would like to know is if I can run this Holley knowing mechanical fuel pump is putting out 7-9 psi & Holley says it needs 6 how will it run with No regulator ??
 
well, i just deleted a whole diatribe... :haha:


glad you got it worked out.. :waytogo: TDC, #1, lace...



you might wanna apologize to quads now... ;) superior carb to a holly any day..
Wished I would’ve kept one & rebuilt it correctly, then I wouldn’t have had to change everything to get this Holley adapted to my engine !!
 
Yes pre-set isn’t precise from Tiawan or ?? Flooding yes it was coming out bowl vent tube & accelerator rod. 2. I got it started & running by adjusting ignition timing , it was retarded too far . 3. I over cranked engine & drained battery. 4. I’ve had this engine in burb for 60-70k miles. 5. Carb. 2&3 almost caught engine etc. on fire . What I would like to know is if I can run this Holley knowing mechanical fuel pump is putting out 7-9 psi & Holley says it needs 6 how will it run with No regulator ??


if you have too much pressure it will blow past the needle/seat, and flood... most carbs are fine at 7 to 9... 6, is what "they" want...
 
"It started &ran 10 seconds & hasn’t run since." Was it a smooth idle or sputtering? Was idle speed normal, fast or barely running? Did it just shut-off, like turning off the key, or sputter and die, like running out of fuel? May give a clue if its fuel system or electrical.

Just so I have it clear, your Sub was running fine then one day wouldnt start. Since then you have replaced the carb 3-times, cap, rotor, plugs, wires, had someone check the timing which was set at 8BTC (assume with engine running) and now the cap/rotor is loose? Did you reverify your timing is set correctly?
He loosened the distributor nut & it never got re tightened , so guessing all the cranking moved it too much. I haven’t had a chance to pursue it today
 
if you have too much pressure it will blow past the needle/seat, and flood... most carbs are fine at 7 to 9... 6, is what "they" want...
That’s a good deal, the motor when it is running sounds like it’s starving & cuts in & out. I would like to take regulator off. Because I think its restricting gas flow & the fuel line is doubled in length to accommodate it in my engine compartment.. I’ve got same carb on my 72 pickup & it doesn’t have a regulator & it runs good.
 
I have only ever run Holleys and I have never once ran a regulator with a mechanical pump, never even checked pressure, just set up the carbs and ran them….glad you got it worked out, this is why I don’t like “buddies” helping me out
 
I had a mechanical pump that wouldn't stay below 7 psi. I had to regulate it. Only one ever.
I have been pleased with my Qjet from Sean Murphy Induction. Got it done over 10 years ago. He made it run well with my solid roller cam.
I have no recent experience with SMI though.
 
We ran Qjets @ 8 psi, so it would make 6 psi @ 6800. Electric pump
 
At one time a sbc pump was available with Bb Chevy diaphragm, I had to run one on hot 327 with a big holley on it. Engine ran out of fuel at the top end on a normal sbc pump.
I have a Jegs brand 80gph pump i tired on my burb before i went electric, normal is 40gph.
 
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