My engine makes carbs flood it. I thought my first carb was bad (wierd though, since it had always been reliable for me, and worked just the week before), so I swapped in a nothing but consistent old 2 bbl, and that floods me out like crazy now too!

This engine has run very healthy in this truck, but if I don't get it to start on the FIRST try, and the first couple of rotations at that, I am absolutely sunk.

All the flooding happens in the two rearmost cylinders, and my truck is about 3 inches higher only in front than stock, but this never happened on my old engine!

It seems to me that the reason it floods so easily is that all of the excess gas goes to only 2 cylinders, but why the heck is there so much gas being pulled in, and is my engines incline really that steep?

I can't depend on a truck that needs half a day to dry if I miss on the first crank.

 

Do you maybe pump the gas to much when you shouldn't? Is the choke open?
Hold the pedal to the floor and that should help clear it out since it will pull in alot more air that way.

 

I dunno about the incline issue (perhaps the carb float) but my Mustang used to do that. A carb rebuild fixed it.... it had a leaking power valve.

 

Possible causes:

(1) User error (too much "pedal pumping" on a cold start)
(2) Float height issue (fuel bowl too full)
(3) Stuck needle/gummed seat (prevents needle from seating and over-fills the fuel bowl)
(4) Blown power valve

It's unlikely that it's related to the engine or the truck itself, because all four of these items can easily happen on more than one carburetor. But anything is possible I guess.

 

I tore my edelbrock 600 cfm apart yesterday. I bought it new a year and a half ago. I have been having a hard time starting the truck since day one. It never starts easily. I always smell gasoline around the truck. Running or sitting.

When I pulled the carb to try another that I had sitting, I saw a pool of gas in the intake manifold. When I tooh it apart, one of the quick change spring and needle seat was stuck all the way down. The spring looks like it came from a bic pen. It is shorter and weaker than the other one. I am pretty sure that is where all my fuel has been coming from.

It is all clean and back together now. The one I put on the other day is running well and starts almost as soon as I hit the key.

 

All good ideas but all stuff I've been through. I pump the carb once or TWICE tops, 3 times floods it, and the choke is closed like it should be.

All the rest of the stuff is broken carb related, which just as it was for you guys, was my first instinct, but I'm now on the second carb, both of which ran and started perfectly on a 400 (408 now) when last removed, and both of which run perfectly on this engine as long as it doesn't flood right off the bat.

Holding down the pedal gets me more life sometimes, but I don't think I've ever successfully started it that way.

When I say it floods hard and fast by the way, I'm saying if I crank it more than 5 seconds, I'm getting almost no pops at all, one single cylinder pop every several rotations, or less, and when I pull the plugs on the rear cylinders, gas spills into my hand.

I am baffled, I can't see why one engine of the same displacement would pull harder than another. I'm using a hi torque starter that I wasn't before, maybe I'm cranking too fast for my own good? This is just such an annoying issue, because although when I finalize my carb and get it really tuned, I will quickly get into the habit of starting it exactly how it likes to be, there will always be those times when I forget and give an extra pump or get distracted and flick the key or something, and I can't be without a car all those times!

You guys think it could be the starter???

 

Also, before I tried the second carb, I tore apart the first one, assuming it was bad, and everything looked good.....

 

I have had a similar issue with my new 408, although I'm fouling most plugs. Went through the Holley 600 but still had the same problem. I was about to put a fuel pump regulator on there because it just seemed like it was very difficult to get the floats set properly. I'm use to being able to set them with an electric fuel pump. This engine has a manual fuel pump. So besides the float issue I had other issues I was ironing out and then I could't get the truck to start anymore and realized the carb wasn't getting any fuel. I could have a blockage somewhere, but I bought a new pump anyways because it's about the only part I haven't replaced. I haven't put the new pump on yet to see if the problem went away. I have never heard of a pump putting out more pressure just before it dies....has anyone else?