Help !! Running super rich.

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So just as I was thinking. Bumping up the timing is going to up the idle. The idle screw is backed all the way out. It’s still to high. Even with the throttle disconnected. Idle is high. And there is no more adjustment for me on the idle screw.
lol. . Thank you guys so far. Even after bumping up the timing the idle mixture screws basically had no affect
 
And as the OP said he tried 2 Holleys and 1 Edelbrock. The Edelbrock doesn't have a power valve to blow out. If fuel dribbles out of those it would probably out of the bowl vents because of a needle/seat/float or float adjustment issue. To @71_dart_swinger , did you by chance change the fuel pump? Excessive fuel pressure will cause a rich run issue. You don't need any more than 5#.
Yes. About 3 months ago I put a new oe mechanical pump. But had no issues with the oe 2bbl set up
 
So just as I was thinking. Bumping up the timing is going to up the idle. The idle screw is backed all the way out. It’s still to high. Even with the throttle disconnected. Idle is high. And there is no more adjustment for me on the idle screw.

Engine needs air and fuel both. Obviously you have (more than) enough fuel. So, where is the air getting into the engine if the throttle blades are all closed?
 
Did this engine flood on you recently? If so, have you checked the oil content?
 
Engine needs air and fuel both. Obviously you have (more than) enough fuel. So, where is the air getting into the engine if the throttle blades are all closed?
Exactly. It’s acting like it’s got a giant vacuum leak . Lol. But I mean. I’ve swapped sbm intakes countless times in 20 years. There’s not a lot to it. I’ve plugged everything off. I’ve replaced gaskets 3 times. Lol. Ram like a top with 2bbl. As soon as I put the 4bbl. Garbage lol
 
Exactly. It’s acting like it’s got a giant vacuum leak . Lol. But I mean. I’ve swapped sbm intakes countless times in 20 years. There’s not a lot to it. I’ve plugged everything off. I’ve replaced gaskets 3 times. Lol. Ram like a top with 2bbl. As soon as I put the 4bbl. Garbage lol
Take some real close up pictures around the base of the carb where it's mounted on the intake. And different angles of the intake/manifold under the hood. Post 'em
 
Took a quick handful

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thanks, I was thinking of where the carb mounts to the intake photos. Thermostat housing looks sealed... LOL Kidding :D i generally don't use the end gaskets with aluminum intakes. If you could get fender height photos up close around the where the carb is mating the intake. Idling high and idle screw backed out are the only real key to this. Wondering if the intake isn't warped. Again, vacuum leaks cause lean issues, but something is going on.
 
thanks, I was thinking of where the carb mounts to the intake photos. Thermostat housing looks sealed... LOL Kidding :D i generally don't use the end gaskets with aluminum intakes. If you could get fender height photos up close around the where the carb is mating the intake. Idling high and idle screw backed out are the only real key to this. Wondering if the intake isn't warped. Again, vacuum leaks cause lean issues, but something is going on.
I don’t usually either. Did when I was younger. Last 2 times I changed them I just put silicone. Figured. I’ll just throw it in.
 
Is it my imagination OR DO THE HEADS look "way low" in ref to the intake?
 
Hang on boys;
On a good running combo with a properly set T-Slot exposure, like my 367, I can set the idle timing anywhere I want to from 5* to 25*, and this does not change the fueling even one tiny bit; The only thing that changes on mine is the idlespeed.
To OP
A couple of things worth mentioning are;
>Dribbling boosters at idle is absolutely NOT right.
>The boosters don't care in which direction the air is going thru them; if they see a pressure drop, they will dump fuel.
>At idle, there is NO WAY the throttles should be open far enough to stimulate the boosters.......... unless your cam-timing is severely retarded.
> the primaries of your 4bbl operate exactly like a 2bbl. Ergo, if the 2bbl system that you took off worked just fine, then a properly functioning 4bbl with CLOSED secondaries, on a properly installed intake; should also work just fine.
>IMO, dribbling boosters at idle, with a closed throttle, can only mean one thing; the liquid level in the bowls is too high.

Try this;
Vent the carburator to atmosphere.
If you have a carbon canister, disconnect it and plug the carb ports.
Open the gas cap.
Disconnect the Vcan and plug the carb port.
If you have power brakes, defeat the vacuum to the booster. (pinch the hose)
Make sure the PCV is hooked up to the port at the front of the carb, and that it is working. The PCV has to dump into the airstream at or near the transfers and idle discharge ports, so that the A/F charge is well-homoginized by the time it gets to the chambers..
Put the mixture screws in the center of their working range; about 3/4 turn on the Holleys, 2.5 turns on the Eddy.
Set the Idle-timing to in the range of 6 to 10 degrees.
Now;
with the engine idling, set the speed screw to whatever keeps the engine running, and note the rpm. Next;
block fuel flow into the carb, and wait. As the fuel level in the bowl(s) drops, the engine should stop flooding, AND the idle speed will go up. Eventually the speed will stop increasing, and remain on that plateau for maybe 15 to 30 seconds; then it will rapidly decrease and stall. While the engine is up on the plateau, back out the curb-idle screw to about 700 rpm, and continue to wait.
This behavior proves that there is too high a liquid level in the bowl. Now you just have to figure out the why of it.

> don't be overly concerned about running the single plain on the mild 360. It may not be ideal, but so what. it ain't the source of your woes.
>To check for a vacuum leak into the valley;
Flip the PCV out of the valve cover, along with all breathers; and plug all the openings. Then install a vacuum/fuel pressure gauge onto the dipstick tube. then start her up;
If you see vacuum on the gauge, you gotta fix that.
If you see the pressure rising,that is normal; but shut the engine off BEFORE it gets to 3 or 4psi. Anything more than that may blow out a seal, a gasket, or worst of all, the rear camplug!
> if you have a fuel pressure tester; look for ~4 psi on your baby, and make sure it holds there when you shut it off, for many many many minutes. If it doesn't, you need to figure out the why of it. If the pump is bleeding down, it may not be that big a deal. But if a float-valve is leaking ..... Badaboom! you gotta fix that.
 
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If you cannot set the idle correctly, the transfer slots are probably too exposed on the secondary side. you should remove the carburetor and adjust the T ports to SQUARE, reinstall. LEAVE the idle speed adjustment ALONE and get it to idle using the timing and the air mixture screws.
 
thanks, I was thinking of where the carb mounts to the intake photos. Thermostat housing looks sealed... LOL Kidding :D i generally don't use the end gaskets with aluminum intakes. If you could get fender height photos up close around the where the carb is mating the intake. Idling high and idle screw backed out are the only real key to this. Wondering if the intake isn't warped. Again, vacuum leaks cause lean issues, but something is going on.
If you cannot set the idle correctly, the transfer slots are probably too exposed on the secondary side. you should remove the carburetor and adjust the T ports to SQUARE, reinstall. LEAVE the idle speed adjustment ALONE and get it to idle using the timing and the air mixture screws.
This is the off the shelf Holley. No adjustments

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Ok, but why wouldn't the other 2 carbs run it properly??? We still have an issue ... ??
 
With all carbs doing it (what are the odds?) maybe a manifold issue? Is it used? Did you inspect for cracks before installing?

Hard to tell from a picture. You might make sure the manifold isn't hanging up on the valve cover lips.

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