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One drawback to carbs if they get dirty then idle problems and cutting out starts happening. That's just part of it. I don't like rebuilding holleys but that's what I ran on most of my cars. I just bought a new carb every other year most of the time
Expensive but lazy approach. I will fully admit my mechanic friends laughed at me about it but my car ran perfect all the time, theirs didn't......
Again I could rebuild them just wasn't worth the effort to me. But the carbs may cost more now, this was years ago, and it might not be worth it now.
One other thing I just thought of it may be running out of gas. If it dies while idling or has dead spots (rev it up more and it picks back up aka only dies at certain points of the pedal with pushing the pedal more getting past the dead spot) then its the carb.
If you rev it up and it just dies anyway no matter what aka will only run x amount of seconds with the time being shorter the more you push the pedal down its fuel delivery.
If its fuel delivery then its a restriction (dirty filter, sock/filter in tanks, collapsing fuel line somewhere) or a bad pump. Most aftermarket low psi pumps are junk and don't last all that long anyways from my experience and 90% of the time people who mod a vehicle doing a low psi pump conversion screw up and put the pump to far from the tank. These pumps are designed to push fuel not pull it.
Basically if the pump is under the hood its done wrong and will cause the problems like mentioned. They need to be as close to the fuel tank as possible. Most people don't understand just how strong those old mechanical pumps are compared to the weak aftermarket electric pumps. The electric ones just cant draw gas reliably from long distances.
Fuel pump is in the back, it makes a loud humming noise. it has gas, i may have done something wrong, but i filled it with premium gas(i hope that not a no-no). im sure its just something with the carb, but when i mess with the timing. it still dies....
I noticed that in your pics you have a fuel pressure gauge inline before the carb. Gets someone to watch that when it dies and see if the pressure is dropping when it quits.
As for premium fuel that's the good stuff so your fine there.
1) Do you have fuel in the filter.
2) If you rev the engine to keep it running...is there still fuel in the filter...it should be full...not bubbles.
3) From the Holley web site....
FUEL PRESSURE: This carburetor has been designed to work best at fuel pressures between 5 and 7 psi. Holley recommends 7 psi at idle, and a minimum 4 psi at engine redline. Three 8” fuel lines can result in adequate (indicated) fuel pressures, but restricted fuel flow. Use of a Holley electric fuel pump at the rear of the vehicle next to the fuel tank assures adequate fuel pressure under even the most
severe operating conditions.
So turn you fuel pressure back up to about 7 psi.
Have you checked the fuel level in the front bowl? I suggested that you remove the sight plug to see what the level was in the bowl. You can adjust the fuel level in the bowl with the engine running.
You loosen the nut on top of the carb and with a screwdriver turn the screw counter-clockwise to raise the fuel level.
@ John A. Maker,
You should show him a pic of the sight plug so he knows which one to remove so he can see when the fuel runs out so he knows the float is set high enough.
I was looking for a good picture of that, but could not find one. Even in the picture above showing how to adjust....the sight plug is in the bowl...good lucking setting the level that way.
Remember that you have the primary fuel bowl in the front to feed normal running conditions. There is a second bowl in the rear for your secondary fuel supply...WOT. So you want to set both levels.
With your low pressure (3 PSI) per your post, you are probably running out of fuel. If the floats are set low too, this will contribute to fuel starvation. When your goosing the throttle to keep it running you are probably pulling fuel from the bottom of the bowl. If you have the air cleaner off (engine not running)....grab the linkage and twist it. You will see at the top of the carb two little nozzles coming out in a "Y" that when you twist the linkage hard will squirt fuel into the throat of the carb. This pulls fuel from the bottom of the bowl. Your linkage will push down on a shaft at the base of the bowl which pushes the other end of the shaft up against a diaphragm which in turn pushes the fuel out the nozzles.
Last edited by John A. Marker; 10-08-2015 at 10:34 AM.
alright jackasses, I'm back. took the damn thing to 2 repair shops, one a goodyear, the 2nd Karl performance. a local performance shop who primarily work on cars like these. They had told me i had a little bit of fuel in the oil. due to a bad carb, low fuel pressure about 1 psi. my fuel pressure gauge is broken. stuck at 5 psi. Ive decided on a holley red, since the people who built this thing went with some weird off brand in-line fuel pump. i dont know what kind of carb to buy. (CFM, street avenger, all that s***).
alright jackasses, I'm back. took the damn thing to 2 repair shops, one a goodyear, the 2nd Karl performance. a local performance shop who primarily work on cars like these. They had told me i had a little bit of fuel in the oil. due to a bad carb, low fuel pressure about 1 psi. my fuel pressure gauge is broken. stuck at 5 psi. Ive decided on a holley red, since the people who built this thing went with some weird off brand in-line fuel pump. i dont know what kind of carb to buy. (CFM, street avenger, all that s***).
I have been in Karl performance once a few years ago. It seemed like a pretty honest and knowledgeable place. (Some sweet cars as well!!)
There are clearly some less friendly individuals on the forum but calling them "jackasses" doesn't help. The best thing you can do is buy some books about your car and a general one of the small block chevy. I'm sure one of the shops you went too could direct you to a few good books. One of the benefits of working on your own vehicles is that you know the quality of work that is done. Ask the performance shop what carburetor to buy I'm sure they have a preference that they like to work with. You should start a build thread with a ton of pictures of your car ( outside, inside, engine, underneath) just so everyone can get an idea of whats going on. Most people are here to help. I don't know what your budget is but a shop like Karl's is probably 100$ an hour so it's worth spending $500 on books and basic tools. I know there is a corvette club in Des Moines, you should probably get involved with them for help as well. Keep us updated!
Its a carburated SBC. It is the easiest engine out there to work on.
Did it run when you bought it?
Is the battery charged?
Does the starter turn over?
If it does not, find out why. Loosen it up and make sure it is not stuck.
You need spark and fuel to make that engine run. Its not hard.
Might be better to ask in a Chevy forum or the C3 section.
They will be less critical.
Once I know the battery is charged and working we can move father along.
I could probably get that car running in under 30 min if it was in front of me.
Dont get upset cause corvette guys are giving you hell. Its a SBC... its not complicated.
Its a carburated SBC. It is the easiest engine out there to work on.
Did it run when you bought it?
Is the battery charged?
Does the starter turn over?
If it does not, find out why. Loosen it up and make sure it is not stuck.
You need spark and fuel to make that engine run. Its not hard.
Might be better to ask in a Chevy forum or the C3 section.
They will be less critical.
Once I know the battery is charged and working we can move father along.
I could probably get that car running in under 30 min if it was in front of me.
Dont get upset cause corvette guys are giving you hell. Its a SBC... its not complicated.
Yes the battery is fine, i just want to know about carb throttle linkage to a 700r4, and the right cfm. i have basic tools.
Been following your thread since day 1.. Just want to send some encouragement your way Dude. I hope you get through it soon, I think everyone here agrees that you are awesome for your attitude and tenacity. Dont let the nay sayers discourage you, you can do it just keep on keeping on.
A 650 CFM is a general start for a SBC. Your mods I would get a 700 to a 750, but I tend to go on the rich side.
Depends on how you tune it, what mods it has and what altitude you live in.
A 650 CFM is a general start for a SBC. Your mods I would get a 700 to a 750, but I tend to go on the rich side.
Depends on how you tune it, what mods it has and what altitude you live in.
Thanks alot! i do plan to drive this thing on a daily basis. thanks for the bracket link too! do you recommend any specific Holley? double pumper, street avenger? i just want one that works at this point, since itll be a DD
Last edited by Levi Kragt; 02-10-2016 at 03:27 AM.
10-07-2015, 08:42 PM
