Carb / intake manifold spacer

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brodphish

brodphish

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I have a Koffel’s 417 striker in a 67 notchback. Fairly frequently the gas will boil or evaporate out and the car is very, very hard to start. It might start 20 times in a row super easy and then just won’t go. I been told a phenolic spacer between the carb and intake would be a solution to stop the heat transfer. Would you agree?

The engine has an Edelbrock Torker II 340 manifold and a Holley 770 Avenger. What kind of spacer would be best? I see there are canvas and plastic. Also would I need the spacer to have the big square opening or the 4 circular holes?

Hedman told me a ping plate might be a solution too.

I can get the car started by taking off the shaker assembly and air cleaner and dropping some fuel in the venture. It’s a 20 minute sweaty process off / on and no fun when I’m out to dinner with my wife or in the parking lot at work.
 
This will definately help alot If not eliminate it . You can also try a return fuel line to tank and will def stop your boil off issue.
 
Hedman told me it’s a thin metal plate that surrounds the carb (like a pie tin?) and block heat transfer. I’d consider it as there’s pretty much space around the carb but going up with a spacer might be a problem due to the shaker.
 
I had this problem with my 318, Torker intake and Edelbrock 600 carb. Here's the thread and all suggestions:
Edelbrock 1405 Help
The carb is getting heat soaked and boiling fuel out of the carb and into the engine. You end up with a flooded engine and little to no fuel in the bowls when you go to hot-start. Ultimately, I fixed the problem by running ethanol free fuel from QT gas stations. I had a 1" open-spacer on bottom and a 1/2" phenolic 4-hole spacer underneath the carb to help keep heat out of the carb. It didn't matter, so I doubt just adding a phenolic spacer will help if you're still using ethanol unleaded fuel. I even messed with float levels, didn't matter. I was told it was other issues and ethanol fuel wasn't the problem. Bottom line, I started using ethanol-free unleaded and the hot start problem went away. My current Duster is the only carb'd hotrod that has ever had this issue, so something on this combination must have had all the stars align. Maybe it's the Edelbrock carb, as I've never had Holley's that did this, only this one Edelbrock carb. Maybe I'll try ethanol laced fuel when I switch engines and run the Holley 750 DP.
 
brodphish said:
a thin metal plate that surrounds the carb
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I had one on my Slant, works. But for your application I would use Edelbrocks base gasket 12410. Open fro the Torker II intake.
Summit Racing #EDL-12410 $38.95 A thick fiber gasket.

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I had a GM heat plate that I used under the carb.
I didn't see that it helped .much, quit using it.
For your problem, I would try the plate, along with a four hole phenolic or plastic spacer
(Engine Masters test, basically: open spacer on a two plane intake, four hole on a single plane. Yrmv)
 
Kendog 170 said:
That's very odd.
Click to expand...
I "think" the Edelbrock 1400 series carburetors are very sensitive to hot start issues with ethanol fuel. I say this because I've never had issues with Holley's and this is my first experience running this type carburetor. You-Tube has video's out addressing the same thing, so it's not just me. I troubleshot the crap out of this carb, including rebuild, various float settings (7/16" (recommended), 1/2"), 4 psi fuel pressure (verified), etc. and couldn't stop the issue until a started running ethanol free fuel from our local QT gas station. I've got it dialed-in and it runs great on my 318, the hot-start issue is my only complaint about the carb. Once cooler weather sets in, I'll be dropping a 360 in that has a fresh Holley awaiting install. I'll see if I have the same issue with it with the ethanol fuel. Hopefully, the OP will fix his problem with a phenolic spacer.
 
I must have had 20 or more customers come in with the same problem and posted this several times. You need to install a return . If you have a mechanical pump ust this filter and run a return to the tank. Your problem will be solved. You could put a 2 inch heat spacer under the carb it will not solve nothing. They are to cool the carb while running for performance gain

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So I've always known to put a return on to solve this issue, however at the moment my brain has forgotten the mechanics of it.

Help a brain out here.

Carb is getting heat soaked, gas boils in the bowls, escapes, down into the intake it goes.

Now the bowl is empty, or less full, and the engine flooded.

Cranking fills the bowl, but it won't start because it's flooded.

I always thought the return should be after the carb so it's always getting cooler gas.
 
Here is what happens. After the engine warms up the ethanol mixed fuel which has a lower boiling point.

When you crank the car the bubbling fuel enters the carburetor.

The floats will not shut the needle and seat because the floats will not float in the bubbling fuel. There is little liquid and more air bubbles not strong enough to lift the float against the pressure of the fuel being dead ended up against the needle and seat under pressure.

The return gives the fuel somewhere to travel to allowing fresh cooler fuel to enter the carb and operate the float

For example

With my electric pump on a switch and no return I could Start the pump and shut it off. Start the car and turn the pump off and on as soon as cool fuel reached the carb the float would work and the car would idle. then I could leave the pump on.

With the return hooked up on the same car I could start the pump and start the car and it would idle perfect .

On the early 80's mopars is what the return filter was used on until they went to fuel injection. That is what you would buy the filter for 1987 318 dodge ram. 1988 were fuel injected.

Put a float in foam suds and it will sink. That is what your fuel looks like when its warm and forced through the needle and seat into the bowl. Its nothing but foam. before and after

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That makes sense, I think I knew that at some point but it was overwritten with newer useless information.

So the OP was shutting off the engine and experiencing a no start.

I imagine at that point the fuel in the carb must also be getting hot enough to bubble, and with more hot bubbling fuel being pushed in past the floatless floats, the engine becomes flooded and will not fire.

Adding fuel manually to the carb is introducing cooler fuel, so it starts.
And possibly the time it takes to r&r the air cleaner may let some heat escape.

I was also thinking my car with efi has no pressure in the line when off, and the fuel actually drains out of the tbs, so it's a non-issue.

Knowing that, I kept starring at the filter with the return thinking it has to be retaining heat, as well as the line up to the carb, but I was missing the bubbling part.

I need to order that filter for my other car. Now that I understand it more better I don't have to overthink it and try to make a return off the carb.

Thanks again fabo.
 
There was a post that someone uses an inline electric fuel pump along with the mechanical pump. This pump allows fuel to pass thru when off. You just turn it on before cranking to refill the bowl. I searched but couldn't find the thread. I do agree that return line is the way to go. This other method would come in handy if you don't drive your car often.
 
Kendog 170 said:
There was a post that someone uses an inline electric fuel pump along with the mechanical pump. This pump allows fuel to pass thru when off. You just turn it on before cranking to refill the bowl. I searched but couldn't find the thread. I do agree that return line is the way to go. This other method would come in handy if you don't drive your car often.
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I tried that it was worse. If you ever use an electric pump on a dead ended fuel system. It just pushes all the foamed fuel into the engine until cool fuel reaches the carb.

No matter what electric pump you use . It must have a return regulator after the carburetor.

When ever we go to the track and watch carbureted race cars restart after going a round or two. You can tell which ones don't have a return. On restart they are revving the engine with a rich black smoke coming out until it clears up.

They sell a sending unit with a return nipple on it. I use that and the vent line used on all 71 and later cars run side by side with the fuel line.
 
Found the return filter, 33054.

Recently put my 62 Dart together, including new tank/sending unit.

What's the best way to install a return to the tank?
 
“I would use Edelbrocks base gasket 12410. Open fro the Torker II intake.
Summit Racing #EDL-12410 $38.95 A thick fiber gasket.”

Makes sense to start here - I wanted to call Edelbrock yesterday or today but couldn’t get to it. I will next week, and report back once installed. Many thanks to all who responded - as Matthon said “thanks again FABO”

One other thing I wanted to mention - I put only BP 91 octane no ethanol gas in it.
 
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I have electric fuel pumps only and have a simple solution that works for me. When I arrive wherever I'm going, I shut off the electric pump and let the engine idle until it nearly dies (runs out of fuel). Usually about 30 seconds or so. Then I shut off the ignition.

When its time to start, simply turn on the fuel pump and let it refill the bowls. Takes about 2-3 seconds. Half a pump shot, hit the key, and boom, they fire right up. No black smoke, no chugging, no drama, etc.

Obviously this only works if you have an electric fuel pump without a mechanical pump also. And it does waste a bit of fuel idling. Depending on the temps, I might not let it idle until all the way close to death but if it's a nice toasty Florida afternoon near 100F, then I let them idle until almost dead. Works for me!!
 
An elec pumps drains back when switched off. It does NOT hold pressure in the line.

I watched a 440 being dynoed earlier this week. It had the Carter 100 gph electric fuel pump & no return line[s]. The engine was stopped/started many times during the testing to make adjustments & it fired up easily every time.
 
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