Float levels were adjusted down. You now have to nudge the car for fuel to come out. I am sure I am missing something somewhere. And the both power valves I have had in it are 6.5's.
Holleys suck. No, Edelbrocks suck! Wait- Quadrajets are the way to go. No way -quadrajets are junk. Why do we keep seeing this over and over.
I'd make sure the fast idle isn't set too high, and holding the plates open, and starting to allow the fuel from the jets to start coming on... Once the fast idle is def. closed, working the idle screws would be the next step... send them in to the seat, and slightly back them off, if it's still too rich, then there has to be fuel coming from another source, or they aren't seating properly. What fuel pressure do you have going into the bowl? If it's an aftermarket pump, you may need a regulator(as many mfg's suggest for "performance" pumps) Holleys are very simple. There's only a few ways to get fuel into the manifold, shouldn't take long to find where it's coming from.
I would make sure its back to how it came from holley. Get the part number and look on their website. Set it back to original and start from there. Had a similar issue with my holley Posted from the TJJ App for iPhone & iPad
That is raw fuel you are getting, no doubt. Not likely it is a blown power valve, i been testing them for about 20 years and the next blown one i get will be the first one. I believe you when you set the proper float height, so scratch that of the list. If it were needle & seat you'd see raw fuel from boosters dripping into the engine ond/or raw fuel dumping frome the vent tube. It would be obvious. That leaves gasketry. I'd look at the metering block gasket, since it has been apart and back together then i would make a guess somebody has replaced the metering block gasket with the wrong one. I'd look at the cutout for the power valve, it should have a tombstone shape. If it has a tombstone shape with an extra notch at the top then that is the problem. The extra notch is for the earlier carbs that have a 'transfer' tube for the accelerator pump shot. Your carb dosn't use the transfer tube, the supply holes have a slight boss and mate direct to the gasket creating a seal. If you have a notch then the accelerator pump circuit is exposed to the cavity for the power valve and it is under a vacuum - in brief fuel will run from the accelerator pump up into the power valve cavity and dribble into the engine below the throttle blades and you won't be able to see it happening. When you have had the carb apart did you notice if the cavity in the throttle body behind the power valve is wet? it shouldn't be and taht is where the problem is.
Not a fan of Holleys, but are we sure it's the carb? I would bolt something else on to verify the issue. With the amount of time spent on that 600 I would make it wall art and go find another 600 (actually I would find an old Carter AFB or an Edelbrock and move on before you total your piston rings from fuel wash.
Check your fuel pressure.I had a simillar experience. 4 carbs, no change. Turned out my off the shelf stock fuel pump from autozone was putting out 13.5 P.S.I. .
Check the needle and seat. It has tiny O-rings that will rot away. Look at them w/ a magnifying to see that they are full and round, and are slightly larger than the brass shaft the are on. Worn O-rings will cause build up/fouling of plugs. Buy a rebuild kit regardless.
DING DING DING !!!!! We have a winner, I had a small block Ford with a mechanical pump same problem dumping fuel running rich and shitty. I went through everything. The problem was too much fuel pressure, I bought a knock off Holley regulator from Autozone (not the cheap dial one) and that was the fix. Get a pressure gauge and check your fuel pressure and start from there.
Yep....that' would be us ...while everybody else on the planet is, for the most part, living quite happily and contentedly in an EFI world! Hell, some of us are still arguing about the merits of having 'over head valves' as opposed to a flathead!!! Mart3406 ======================
I'm in the power valve camp..... There is a great post in here with the "formula" for selecting the correct one......I'm for going that route first,......"R&R" troubleshooting can get real pricey. Warped parts... Be gentle, when tightening bowl screws.... More, in this case, is not "better". 4TTRUK
I think this to be excellent advice. Sounds like you have checked over the carb pretty well. If you do not have another carb to try: (1) compression test (even if the engine is a fresh rebuild) (2) ignition test (3) fuel delivery test (PRESSURE and volume) If all three of these are good, THEN go back to the carburetor. Jon
Best advice yet! Don't assume that a mechanical fuel pump can't be too high pressure for a carb! I've seen stock mechanical pumps that easily put out 8-12 lbs. pressure and neither Holley or Edelbrock carbs like pressures over 6 lbs. Get a gauge after the pump and see what it's putting out before you get to carried away changing things in the carb.
Where were you last year. I will pick one up tonight on the way home and then put the carb back together again and check some of the items listed that I have not checked yet. Thanks again everyone. (Well almost everyone).
For all our sakes & sanity, please tell us what fixes this problem. There is a reason many folks love Holley carbs & that is they are able to be adjusted dozens of ways & that also can be a problem .
I try and let people know what the solution was regardless of how bad it makes me look. Someone else will have the same problem someday (Sorry if it you).
I don't normally do videos so let see if this works. Hummm not what I was expecting. I am running at 7lb fuel pressure and I did find a second gasket on the power valve when I was looking thing over, Took the car out to test drive it and lost a u-joint clip. (That little clip is a VERY crucial part of the drive train) limped it back to the garage and will be repairing drive shaft and any other damage tonight.
yah, 7 lbs is a bit much for the needle and seat to handle - would have been worse with an AFB or Edelbrock though. I would try a regulator and you fixed the power valve, so I think you found it. Let us know how it runs when you can keep the drive shaft in it!
Will the regulator have a gauge on it or do I need to re-rout my fuel line to get all the extra stuff in there? I thought a holley would die if you adjusted both air screw all the way in also.... I have the air screw at about 1 to 1-1/4 turns out to get it running smooth. It was mentioned that I should adjust the carb with the car in gear but was not told weather the brakes(power)need to be applied or if the car should be running on stands? Lots of incomplete info given to me and I am trying to decipher something that is not in my wheel house to start with.
Set it idling in gear with the brakes on - you want it working against the converter, like you are sitting at a stoplight. Slowly turn the mixture screws in until it starts to slow down, then back them out 1/4 to 1/2 turn, Keep them even as well, turn each one in a 1/4 turn at a time to find the spot.
I like the idea of having someone sitting in the car applying the brakes for all four wheels for you while making this adjustment. Parking brakes don't stop a car as well as you might think, or hope. When you're doing this kind of an adjustment it's not unusual to get things too rich or too lean and the engine may start to stumble and miss and die. It's hard to fight the temptation to give the throttle a whack by hand to keep it running. Standing outside of the car, maybe in front of it, in gear, possibly by yourself... things can get real ugly real quick.
Sorry Dick, post 38 didn't win, it was my post 30 But WTF no OPs read these responses or possible solutions anyway........
Am I missing something Fenders? I have about 20 pages of paper in my garage so I can READ what has been offered for advise and with your help and others I have found two problems so far. If you are just trying to add to your post count, find a different thread. If I took this the wrong way, please clarify it for me.
Not intended personally, I was commenting on my general impression of some who ask for advice then ignore it. I'm glad you are not and look forward to your posting the solutions to your troubles.
Thanks for the clarification. As I mentioned earlier, I had to replace the u-joint last night and will be heading off to the performance shop after work to find a fuel regular. Will follow up as soon as I get that installed.
Ive had nothing but problems with every edelbrock ive touched, but every wrecking yard rebuilt holley ive worked on or ran work like a champ...
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