Always make sure you ignition is new or known to be in excellent shape before you make changes to your carb. Fuel pump must keep min and max pressure at all times 4.5 to 5psi. If its a known pump and makes more than 5 psi then youll need a reg at all times. Also make sure you dont have something in your tank disrupting fuel flow and make sure you have a filter before and possibly a glass one after your pump to monitor for debris. I try never make changes to any of these parts in the same day or same time.
running a carter avs has recent prof. rebuild. ignition is fine .now have a problem with the idle raising and goes low then after a min car dies and or in gear.when i go to reverse or drive it dies i have to keep feathering the pedal to make the car stay idleing.also just installed a new edelbrock manifold and new carb base gasket new cap and rotor on the hei and has new vacume lines(power brakes)timing is 12 intial around 38 at 2800 rpm.running a small 4-7 psi electric pump with regulator set at 5.5... with or with out the reg still has the problem?anyone local that can rule out this problem sprayed carb cleaner around the carb& manifold no signs of a leak also i do not have a hard starting problem turns over on the first bump could there be a vacume leak inside the carb?
also checked the plugs they are a nice tan..also checked firing order and everyhing is good and connected..
out of curiousity....what type of gas tank? i had issues with a faulty gas cap , that wouldn't vent....and had similiar issues.
67 mustang gas tank.will have to double check the cap but you are saying that if it doesnt vent.it would cause the idle to raise or drop?
my double pumper just did the same thing...i had it rebuilt and it cured it ...but if it did it 1 time your more than likely gonna have to clean or maybe even replace the needle and seat...i took off the manual pump and put a electric pump on and thats when it started..never could get it right with the electric pump
first page was enough-i'm not reading the full thread.... I'm so sick and tired of the "holleys are the Debil, and they should be taken off of your motazzz!" The op obviously had bowl filling problems, either with the fuel pressure or the needle/seat/float. hmmmm. Edelbrocks, Carters, Rochesters and Stroms ALL have fuel pressure limits and needle/seats Just because YOU couldn't make a Holley work doesn't mean the rest of us can't. My 850 runs just fine, thank you. -rick
problem that i had was floats not adjusted properly.fixed that.got rid of it because there were other problems with the carb so a friend gave me a rebuilt carter avs .i have nothing against holleys.and dont know why people were bitching on this thread about throwing the holley away and stuff like that.because it didnt help me at all...so i still have this odd problem. so can any one help.........
by odd problem i mean the idle is going high to low then dying and if i drive it and put it in park the idle goes to 1200 then eventually dies.also someone told me today that i might need bigger jets any truth to that? also going to throw a 600 holley that was the only carb that would stay idleling..
If you're still having overflow problems from bowl vents, then first you need to verify 3 things: 1.Is the carb your friend gave you clean (needle/seat). 2. Is your fuel pressure appropriate for the carb you're running. -different carbs take different pressures "ideally" but they're under 8 lbs. 3. Are you running a QUALITY filter. Change it anyway. there really should not be any other reason for carb bowl overflow- i would check the accuracy of your pressure gague as it sounds like it takes a bit to fill up then overflow. are the bowls empty when it starts? (long time cranking to get her going)? are you giving it a pump during startup? (starting off of the pump shot will sometimes hide an empty/low bowl) Is it overflowing from BOTH vents? i dont remember what regulator you're using and what pump you're using. if you're running a double pumper then you're mill either needs it or not- and if it needs it, step up to a return style fuel system with a return style regulator and get true control over your fuel. be as specific as possible when describing your equipment an issues, and let's get this handled- I'd like to see your holley back on the mill since it USED to run right- then we go from there, if that's not possible, then we'll just deal with what we got....
dont have the overflow problem any more this is a different problem having idle issues please read the rest of the thread.thanks
Just bump the timing up one degree at a time until it runs good and still starts good. What ever you end up with is the correct number of timing for your peticular motor and set-up. Sometimes thats a lot of raod testing but worth the effort. I always find a good freeway service road, take my timing light, and start playing. My two cents.
You might need to check you time chain. If you put the motor together with one of those timing chains that allows you to advance or retard the cam timing, you might make sure you are using the correct marks with each other. I am not saying this is your problem but, I have seen some doggy motors that the timing chain was installed incorrectly.
its got a pete jackson gear drive and motor was done by a well known professional engine builder here in orange county..
you could also have a intake manifold leaking on the inside or cracked. I know most people are going to say that it would suck oil if the intake leaks on the insde of the lifter valley, but not always true. Also what carb was the manoifold orginally designed for? Are you using the rubber seals on the front and back of the intake manifold?
I f the heads have ever been milled or resurfaced a lot, the rubber seal will hold the manifold up enough that the intake gaskets will leak on the inside and not on the top. If this is the case,Use silcone on the ends and MGR extra thick intake set.
I f the intake was originally for a Q=jet carb, there is a thin plate(.060 or so) that has to be installed under the carb when Holley or Edelebrock bolt pattern carbs are installed.
no leaks sprayed brakleen alaround the carb and manifold.has brand new intake and layed the silicone on very thick..
Try finding out if it is lean or rich at idle. While it is idling, (and be careful!), slowly close the choke blade by hand. If it speeds up, it's getting too much air. If it slows, it's getting too much gas. This will help us figure out what to look for.
i have placed my hand over the carb rpms are bout 900 and it changes trying to remember if its lower or raises will double check but if that the case what next.thanks
the earlier post that the fuel pressure bounces from around 5-7,or 8 ish at 3000 rpm means that the float cant keep the needle/seat controlled and it's either sticking, or more likely being pushed open. Choking it by hand and getting a raised rpm indicates a lean mixture, either by tune or by vacuum leak. Since you didn't mention pulling the intake, lets assume that you haven't acquired a vacuum leak spontaneously (but it's possible i guess) Is the carter new? anyone dial it in or fresh out the box? I'd check the vacuum lines and the other end as to what they're attached to.
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