The Stovebolt Site Forums The Shop Area The HiPo Shop Chevy 350 with Edelbrock 600 cfm

My truck will fire up instantly after it has been sitting all night, but after driving around I have to turn the engine over for about 3 seconds before it fires. It has a mechanical fuel pump. Do you think I should add an electric fuel pump?

It has electronic ignition and is just a basic 225hp 350, if that matters.

Might want to check to ensure your fuel lines aren't too close to heat source ( exhaust, block ). Also check / replace fuel filter and filters in carb ?

Does it act like it is flooded when you go to start it? After you shut it off look down the carb throat & see if any gas is dripping into the bore. If so you could have too much fuel pressure or dirt in the needle & seat or a bad float. Could the heat rizor valve be stuck shut sending too much heat to the carb base causeing the gas to percolate.

I had the same carb do the same thing on a 283. I added a 1/2" thick phenolic carb spacer. It's not perfect, but 95% better now.

Thanks for the advice, I will report back once I've had a chance to examine the carb in more detail.

Ok, took it for a long spin and there is no gas dripping but the secondary "butterfly" things were pretty wet. I usually don't get into the secondary while driving. Maybe that would account for my bad gas mileage (9.5)?

I was on Edelbrocks tech site and noticed this post:

Q: Which side of the carburetor do I put my dist vacuum line to?

A: Generally the distributor vacuum line goes to the timed (pass side of carburetor) port. This is mandatory on emission controlled applications.

Mine was on the drivers side. I moved it to the passenger side and noticed the plug on the p-side was cracked.Taped it up and plugged the drivers side.

I also pull a spark plug or two this weekend to see what's going on.

So what to make of this? Any ideas?

What's the choke arrangement?
You can get a calibration kit to set the carb up for your vehicle, driving style, and other conditions. I have a factory reman 600 on an sbc...it runs rich.

cm

starfire4,
Electric choke. Wish I had gone with a manual though.
I thought mine was running rich, but I pulled a spark plug last night and it was in perfect condition. I did notice that moving the distributor vacuum line to the p-side port let the engine run smoother. The starting hasn't changed much. I might try adding a spacer like mentioned by Southtowns27.

Assume you have a stock fuel pump. 6 psi max for a standard carb. No high volume pump should be used on a stock 350.
If pump is stock, then a question: is carb new? rebuilt? by whom? when?. If it was operating fine then started doing this, it's probably not the float, but if it's been "rebuilt" reciently then I am aiming towards float level and float drop adjustments. Edelbrock is a very easy one to rebuild (Carter two piece). Also: 3 seconds is not a lot of time, so it's not flooded and it is getting gas. It is acting backwards, usually should take a little longer when cold than hot. Seems like it's the float adjustment because after overnite it evaps and drains a little so that the level is good for fast start, then fills and remains too high of a level and is slightly flooded. A sagging choke butterfly can be the problem as indicated by others here. But 3 seconds is not bad. Try various start procedures after it is hot. A one pump, a two pump, three pump.... of the gas pedal.

You mention the carb has an electric choke.When you start the first time of the day the carb is ambiant temperature.For the rest of the day there will be some heat in the motor.Therefore the choke will not work the same way.

I had a similar problem on a fresh rebuilt engine, I won't say what brand. I too put in a spacer under the carb and it made a world of difference. I was also told to clip wooden clothes pins to the fuel line, if it makes a difference then the fuel line is getting too hot. The clothes pins serve as a heat sink.

wood is not a heat sink, it has zero conductivity. I hereby "bust" this myth. Vapor lock itself is almost a myth. There are not too many mechanics who use that excuse anymore. It was always Fuel pressure problems, carb or timing, fast moving fuel stays coolish and hardly has time to get hot. Clothespins are for clothes.

Maybe not zero, but very low indeed. I would disagree about an insulator not making a difference. Phenolic spacers have been used to good effect for a long time. It's not the temp of the incoming fuel, it's the manifold heat boiling the fuel in the bowl that's the problem. Phenolic, or any other insulating material, will help this condition.

No one has said that spacers do not make a difference. There is nothing to disagree with. The point about zero is that it has no conductivity and will not work as a heat sink. We don't need you to sharpen every point on every post as you do: like.... "but very low indeed". That's just posting for numbers not for info. You comment and ride piggyback on everyone elses answers and disagree with an imaginary poster.
In my opinion: the subject of vapor lock, boiling gas out of carb and all that does not apply here. He starts in 3 seconds, it does not die when running and 3 seconds is NOT hard starting. It is not vapor lock or anything like vapor lock. The vehicle is not exhibiting what was called vapor lock, that is the wrong track to be on. He is not stranded along the road waiting for the engine to cool off. There are many good comments and ideas expressed here regarding other possible issues.

Bartamos,

Have bad day? Merry Christmas.

And everything has conductivity. Just some more than others.

I think we all value both of you guys opinions. We are all just looking for friendly info.

Merry Christmas!

Cool it dudes or I'll have to take your toys away.

yeash seems the forum has goten a mean spirit over the holidays lol saw bout the same thing happen to a guy about rear end gears this is a time to be happy and spread joy tax time is for bad mood :P

I don't have a mean spirit. if you are speaking of me. My spirit is fine. I just call's em as I see's em in any season. I don't think any more comments about my comment would be fruitful. 4 is good.

What was the question again?

Im not sure when the last time u checked the timing, but i always like to make sure its right before i start messing with the carb.

Back to the original question...
I think that a 3 second start is nothing to be overly concerned about. That is acceptable. Let me ask....Are you pumping the gas when the engine is warm, or are you just turning the key?
..and no I don't think you need an electric fuel pump.

Minnehaha is right on! and do what I proposed at the end of my post on page 1.

My opinion?...Put on the correct Quad with the correct choke set-up on and be done with it. Performance carbs are for performance, not drivability. The Quad is one of the best carbs out there! My old wood hauler starts in about 1 revolution, every time,
Scott

I have run the 600 edelbrock for years on both my trucks. You need the spacer under the carb. After it has been sitting and you try to start it push the gas pedal just a little and it should start faster dont pump it or anything just open it a little. Try this it will work.