Just finished installing a 600 CFM Holley 4160 on a bone stock 1982 f100 with a 302. I swapped the stock manifold out for an Edelbrock that went smooth enough. I used Felpro gaskets on the heads and a big bead of RTV on the block. New plugs, plug wires, new coil, put a hole new distributor on because the vacuum advance didn’t work on the old, one and you can’t buy it by itself. Anyway we got the carburetor on and all the vacuum ports plugged or connected. After a couple of cranks it fired up. The truck idled high about 2000 ran for 5-10 min we tried to adjust timing and air/fuel then it died. Next attempt resulted in massive FLAME BALL backfire, very exciting. It ran a couple more times but always with high idle, hitting the gas just kills it. As of last night when I left the garage it wasn’t running at all. If I look strait down into the barrels the jets are dripping fuel, I bought some smaller jets to try out. Someone told me it may also be a bad vacuum leak, perhaps around the intake due to poor gasket installation!?! Any ideas?

 

Hi,

If fuel is dripping down the throat of the carb the first thing I would check is the fuel level in the bowl. I would hold off on the new jets. If you remove the plug(screw) on the side of the bowl gas should just trickle out if you rock the truck side to side. In other words the gas level should be even with the bottom of the plug hole. If incorrect adjust with the inlet valve control screw on top of the bowl. CW on the screw will lower the fuel level.

Since you had the dissy out double check your timing to make sure it is correct. Also, double check that the plug wires are not crossed up. I know, but it happens.

You say that the idle is hi around 2000rpm. Is the choke opening all of the way? If not, adjust this. There is also a fast idle speed control screw on the passenger side of the carb. It's located with the choke linkage and is kinda hard to get to but you might try adjusting this when the carb is cold and the choke is activated. I think I set mine for around 1200rpm.

You really can't adjust the timing with the engine idleing that high. At 2000rpm your timing is being influenced by the centrifical advance and your readings will be wrong. You will need to be down around 700 or so and have the Vac advance line disconnected and plugged.

Good luck and let us know how it turns out.

 

Make sure that you have a good inline fuel filter before the carb. Holleys are very dirt sensitive it only takes a small piece of something to hang the needle and seat open.
Was the fuel dumping into the carb after it wasn't running? That's no good. I wo remove the needle and seats, clean them out by blowing thru thr pointed seat area. Reinstall them about 1/2way threaded down into the bowl. remove the site plug in the passengerside of the bowl. Start it up and adjust the fuel level until it is just below the sight hole. If you rock the truck a bit, it should slosh out. Reinstall the site plugs and make sure that the set screws are tight on the needle and seats. If you are still having problems, then either the choke linkage has the throttle stepped up ,you have a large vacuum leak and or your timing is out of whack.
Jimmy

 

Well I messed with it for about 2 hrs last night after work, still wouldn’t start. The battery was almost completely dead. It acted like it wanted to start but just wasn’t quite right. I gave up and got some sleep. My friend worked on it for a few hrs after he got off work, he called me a few min ago to tell me its running. Apparently the vacuum break booster is out and that was causing the vacuum leak. I bought a new one on my lunch break and will be putting that on tonight. I also got a pack of secondary springs, I know the carburetor has a #69 jet in it I bought a 66 and a 64 to see if can get the mixture right, any advice on springs and jetting? Thanks for all your help. You guys rock!

 

Hey that's good news!

As for selecting the correct jet size, I don't know a whole lot about this but I will tell you what I do know.

I read about the following procedure on this site awhile back. Hook up a vacuum gauge to a manifold port. Drive the truck with it's original jets installed at a steady hiway speed on level ground and record the Vac reading.

Change the jets and repeat your drive at the same steady speed noteing the Vac reading. Repeat this with differnet jets until you find the one's that give you the strongest Vac reading. It is also best if you do each drive at times that the air temp and humidity are are as close as possable for each drive.

Good luck,

 

Drive it then check the spark plugs. If they are black it's too rich, if they are clean looking and it doesn't ping, then I would leave it alone.
As for the spring in the secondaries, I would drive it and see at what rpm that the open. Should be around 2500rpm. Much less than that and it will bog when they open.
They usually come with the black spring which is the heaviest so that it won't open if the carb is too big for the engine.
If it doesn't open, you can try the natural spring. Don't use the yellow one. It will open too soon and give you a hesitation.
Jimmy

 

with it backfiring thry the carb, you might want to check the power valve , or a least be aware that it may be blown, good luck , bob