Cranking problem

[rally]

Hey guys,

If I start my truck for the first time that day, I turn the key to on, press the pedal down all the way, release, then press the pedal down slightly and start the truck. Most of the time, it fires right up without a problem.

However, if I drive around and park it, say to go into a store, then come back out and try to start it, sometimes it just cranks and cranks before finally starting. Sometimes, it fires right up again.

What is the cause in the difference starting for the first time that day and starting after parking it for a few minutes? The only thing I can think of is that after I park it and try to start it again, I'm going through the same routine: turn key to on, press pedal all the way down, etc...maybe that's unnecessary and I'm flooding it a bit?

I'm not sure if there's something I can do to fix this to where it's more consistent with it's starting, or if there's something I need to change in my process for starting? I don't think the carb is draining out or anything, especially since the first time I start it that day it fires right up. Suggestions?

[davepl]

It's not fuel injected, so are you using the pedal at all? Normally once it's hot some vehicles require the throttle to be cracked open a little when cranking in order to start.

Do NOT do the "full pedal to the floor" except when cold. The point of that is to prime the engine with the accelerator pump and to set the choke, and I bet that's flooding it a little when you do it when its warm.

So, cold start: pump a couple of times, no foot, crank
Hot start: just crank or crack the throttle a little and crank

You CANNOT make it "consistent" cold start and warm start because they are different functions and you need to operate different mechanisms. It's not just a throttle blade, you have choke springs and doors and accelerator pump diagraprahms all trying to work together. In some ways its a lot more complicated than EFI.

[cdowns]

if you do not have a phenolic spacer under the carb the heat will cause the fuel in the carb to perculate

[lutronjim]

Or a sticky needle in the float assembly

[rally]

Originally Posted by cdowns

if you do not have a phenolic spacer under the carb the heat will cause the fuel in the carb to perculate

Probably a stupid question, but what is a phenolic spacer?

[rally]

Originally Posted by lutronjim

Or a sticky needle in the float assembly

It LOOKS like a fairly new carb. When I pull the cleaner and stuff off and look down into it, it doesn't look to have any buildup or anything. Any suggestions on how to clean it? Throttle body cleaner from autozone? I might have to pull it to put a phenolic spacer on, so I might as well clean it.

[cdowns]

Originally Posted by rally

Probably a stupid question, but what is a phenolic spacer?

it is a spacer with holes drilled in it but is made of nonmetallic stuff to stop the heat flow from the manifold to the carb

[geezer#99]

Like this.
http://www.speedwaymotors.com/Moroso...y-390,616.html

[Steeveedee]

2BBL or 4BBL? It makes a difference. The 2BBL will have a hollow brass float, the 4BBL (if stock) will be a QuadraJet and will (most likely) have a composition float. There are different things that can happen based on which one you have. It has already been pointed out that you shouldn't push the pedal all the way to the floor when hot. I doubt that there is any bleed down from the needle and seat, or percolation after you shut it off, based, as you said, on the fact that it starts cold. If the bowl was empty, it would still crank for a bit before it started, cold.

Have you always had this problem? If it is a recent occurrence, Think about what has changed from when it did work properly.

[rally]

Originally Posted by Steeveedee

2BBL or 4BBL? It makes a difference. The 2BBL will have a hollow brass float, the 4BBL (if stock) will be a QuadraJet and will (most likely) have a composition float. There are different things that can happen based on which one you have. It has already been pointed out that you shouldn't push the pedal all the way to the floor when hot. I doubt that there is any bleed down from the needle and seat, or percolation after you shut it off, based, as you said, on the fact that it starts cold. If the bowl was empty, it would still crank for a bit before it started, cold.

Have you always had this problem? If it is a recent occurrence, Think about what has changed from when it did work properly.

It's an Edelbrock 1406 4BBL from what I can gather on the front stamp and looking into it. I haven't had the truck for very long, and it spent about 2 weeks in the shop when I bought it to get everything sealed back up. I noticed it a couple of days after I got it back. They did set the timing, but it runs fine and starts quick when it wants to start quick, so I don't think it has anything to do with timing itself. I'm probably just flooding it when I start it after it's already hot.