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well I bought a new Holley 600 carburetor and slapped it on.
primed it and stared it up, it started and revved to 2500+rpm shut it off instantly.
checked for fuel leaks, then checked the curb idle was all the out just barely touching,
air mixtures were 1.5 turns out. Started it again same thing.
Loosened up the choke, disconnected the power.
Turned the choke clockwise to the last line. started again same thing revved to 2500rpms.
Turned it past the line about an inch started and it was barely running.
Brought it back a little and again revving around 2500rpms shut it instantly.
the fast idle screw is such a PITA to get to I think I will pull the carb off and see if it is causing the issue. so freaking aggravating. if I was back in my 20's one of those carburetors would of got the sledgehammer. my patience is better 30 years later but not much.;)
what do you think, could it be the fast idle causing this?
also it has a spread bore plate on it can I use the open gasket that came with the Holley or do I need the spread bore gasket? I have 2 sets of each.
Wait-what..... spread bore plate? Did you have a 4300D spreadbore carb and is that what you have for an intake?
 

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Wait-what..... spread bore plate? Did you have a 4300D spreadbore carb and is that what you have for an intake?
I read that on my out from work, so didn't really have a chance to respond. Do you have a Holley with a spreadbore base plate, or do you have an intake with a spreadbore configuration and you're trying to install a Holley square bore carburetor on it with an adapter plate? What do you have?
 

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Discussion Starter · #23 ·
sorry, I think its square bore plate,.plate on it.
the 4300 has no tag on it, getting ready to call Carbs-R-Us to see what they charge to rebuild my 4300. its pretty dirty on the inside.
the Holley is a 4160.
The gasket that is on it is this one Felpro universal its the same one that was on the 4300 originally. the Holley came with the open gasket.
I didnt have time to pull the carb last night, maybe tonight.
 

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Discussion Starter · #25 ·
well I turned the fast idle screw all the way out last night, fired her up and still revved high like 2000rpm now, turned the electric choke to the right and tried again, ran around 1500rpm then slowly idled down and stalled and then I couldn't get it to start again.:mad:
checked spark all good, checked on gas squirting in the carb it squirts. pushed it back in the garage and poured a beer. This is baffling me, because if I put the 4300 back on it she fires up runs fine at idle but coughs and sputters on acceleration which I know is the carburetor being dirty and in need of a overhaul. This is a brand new Holley. when I was younger I swapped carbs on my cars and my friends cars and never had this many problems, a few adjustments and they ran great. I have new gaskets coming tomorrow to swap out just in case it is leaking. any ideas? the summer will be over by the time I get it running at this rate.
 

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Discussion Starter · #26 ·
ok Got it fixed now!!!
wasnt a vacuum leak, turns out the fast idle screw from the factory must of been set almost all the way in and it was not dropping out of fast idle.
I tried starting it this morning and nothing, it was like it wasnt getting fuel or spark. looked down the carb and hit the throttle and saw the squirt of fuel, so I moved onto the spark. spark plug wire has spark, checked the points they were sparking. tried to start it again, same thing. pulled the Holley of put my old 4300 on it and it fired right up.
so now I was like this is crazy. took the Holley to the bench and opened it up, well the front bowl needle was stuck closed.
dont ask me how, i had checked the first day and the side screw had fuel coming out when i rocked the car. maybe due to the constant revving and shutting down or something. anyway I took it out and blew some air through it. while I had it off I looked at the fast idle screw and it was still out, Turned it about 5 more turns then it was just touching the cam.
put it back on the car and after 5 or so cranks she fired up and was purring like a kitten.
Didnt have time to tune it with the vacuum gauge since the storm clouds was a rolling in. so its back in the garage and I was happy with the progress.
Two lessons learned
1 never trust the factory settings, check everything
2 I think I said before slow down and look at everything.
 
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