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Old 04-21-2010, 11:36 AM   #1
D-Rat
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hard starting with new Edelbrock when warm

The 1406 on my 400 makes cold starts a breeze...fires up on the first crank every time. The problem is when the truck is warm, it doesn't like to start and usually requires me to pump the gas pretty good while turning the starter. Eventually it catches.

What do I need to adjust? The carb is brand new and unaltered. Let's assume timing is fine becuase this was not an issue with the previous carb, though it did have other issues.

I'm also down on "stab it" power compared to the 730CFM Holley I took off. Ideas?

I'm not crazy about rejetting, etc., as I've never torn one of these down, but if that's the only option, well...
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Old 04-21-2010, 12:09 PM   #2
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Re: hard starting with new Edelbrock when warm

Sounds too rich. Next hot start don't pump it, just hold the throttle half open and crank. If it starts right up then you are definitely too rich.
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Old 04-21-2010, 12:12 PM   #3
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Re: hard starting with new Edelbrock when warm

Your "stab it" power is down because it's only 600cfm.
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Old 04-21-2010, 12:19 PM   #4
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Re: hard starting with new Edelbrock when warm

do you have a carb spacer like edelbrock recomends in the instruction booklet so that the fuel doesnt boil
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Old 04-21-2010, 12:29 PM   #5
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Re: hard starting with new Edelbrock when warm

Is the choke plate open when it is warm? If not, then the choke is not working and it needs to be fixed/replaced. When you pump the gas, you are actually opening the butteflies and allowing more air to enter, which is what the engine needs when warm. A warm engine should not need to be pumped to start up. However, when the engine is cold the choke plate needs to be closed, which explains why your cold starting is great. A closed choke plate will also kill your power. The cfm is fine for your engine and should not be a source of your "stab it" power issues.

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Old 04-21-2010, 01:20 PM   #6
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Re: hard starting with new Edelbrock when warm

Are you getting any hesitation on take off? And re-jetting an Edelbrock is quite simple, and can be done while it is on the engine although I doubt this is your starting problem. Edelbrock makes a nice jet kit for this. Also, like Cdowns said, a spacer is recommended.

What type of choke did you get, electric or manual?

even though your last carb worked well, its a good time to check you timing anyways. The PO of my truck had the timing way to advanced and it would be a bear to start in certain conditions.
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Old 04-21-2010, 01:24 PM   #7
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Re: hard starting with new Edelbrock when warm

Quote:
Originally Posted by cdowns View Post
do you have a carb spacer like edelbrock recomends in the instruction booklet so that the fuel doesnt boil

Thats what I would guess
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Old 04-21-2010, 01:33 PM   #8
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Re: hard starting with new Edelbrock when warm

Choke is working fine.

There is no carb spacer. It's bolted directly to the manifold with just the gasket in between. That explanation makes sense.

What part are others running here? How thick? Anyone have one laying around they're not using?
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Old 04-21-2010, 01:41 PM   #9
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Re: hard starting with new Edelbrock when warm

Quote:
Originally Posted by D-Rat View Post
Choke is working fine.

There is no carb spacer. It's bolted directly to the manifold with just the gasket in between. That explanation makes sense.

What part are others running here? How thick? Anyone have one laying around they're not using?
Do you have a spread bore or square bore intake?
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Old 04-21-2010, 01:52 PM   #10
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Re: hard starting with new Edelbrock when warm

my truck has a dual plane intake..never boiled

my surburban has a open intake..it boiled until I installed the spacer
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Old 04-21-2010, 02:05 PM   #11
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Re: hard starting with new Edelbrock when warm

Quote:
Originally Posted by Leviticus View Post
Do you have a spread bore or square bore intake?
Not sure I know the difference, but it's one big hole. It's an Edelbrock RPM intake if that helps.


I'm looking at spacers...which is better - open design or 4 hole?
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Old 04-21-2010, 02:07 PM   #12
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Re: hard starting with new Edelbrock when warm

use the 4 hole

that should stop your problems..and it will also help you idle circuit
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Old 04-21-2010, 02:26 PM   #13
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Re: hard starting with new Edelbrock when warm

Quote:
Originally Posted by D-Rat View Post
Not sure I know the difference, but it's one big hole. It's an Edelbrock RPM intake if that helps.


I'm looking at spacers...which is better - open design or 4 hole?
If it is one open passage (not divided) than you most likely have a single plane square bore. You should be able to pick up a carb spacer at your local auto parts store/speed shop.

Just make sure it will match your carb and intake. The 4 hole designs should help as well, as Charlie said.

Here is a pic of a spread bore dual plane intake for reference.

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Old 04-21-2010, 02:46 PM   #14
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Re: hard starting with new Edelbrock when warm

I had the same problem until I installed a 4 hole plastic spacer to insulate the carb from the manifold heat.
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Old 04-21-2010, 02:50 PM   #15
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Re: hard starting with new Edelbrock when warm

Definitely sounds like a "Heat Soak" issue. I would try the phenolic spacer to remove the heat from the bowls of the carb. I am running one on my stroker engine with the Edelbrock carb and intake.
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Old 04-21-2010, 03:28 PM   #16
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Re: hard starting with new Edelbrock when warm

Nabbed a 1/2" one off ebay new with gaskets and studs for $22.99 shipped. Will see how that works. Thanks guys.
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Old 04-22-2010, 04:31 PM   #17
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Re: hard starting with new Edelbrock when warm

Most of the edelbrocks i have require about 1/4 throttle push with no pumping when warm. I have been told that all these drip a little fuel out the bottom? Sometimes i give mine 1 pump before i start it?
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Old 04-22-2010, 09:38 PM   #18
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Re: hard starting with new Edelbrock when warm

Hey D-RAT I'm having the same problem with my 1406, I had a 1405 and it would start fine every time, the 1406 takes a while to start when hot, I have an edelbrock performer intake so it has the 4 holes. let me know if that spacer fixes the problem.
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Old 04-23-2010, 12:46 PM   #19
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Re: hard starting with new Edelbrock when warm

will do.
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Old 04-23-2010, 12:54 PM   #20
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Re: hard starting with new Edelbrock when warm

Don't me to hijack, but since you all are talking about Edelbrock carbs.

What would be the best one for my stock '73 454 with an manual transmission.

Thank you.

Danny
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Old 04-23-2010, 03:06 PM   #21
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Re: hard starting with new Edelbrock when warm

The 600CFM is marginal for my small block 400 but might work ok on a bigger motor with larger jets. A stock '73 454 is pretty low compression and probably doesn't have much in the way of high flow heads, so you might not get much benefit out of anything larger.
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Old 04-25-2010, 10:30 AM   #22
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Re: hard starting with new Edelbrock when warm

Spacer seems to have done the trick!
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