Edelbrock 1406 tuning question

[Glen]

I run the same sbc, intake, hei, and manifolds in my truck and buick.  I recently put the same 1406 on my truck so both vehicle are set up identically.
I also have the identical problem on both so im hoping it is a common edelbrock concern and one of you guys has already beat the problem.

the carb is great, i havent modified anything.  The symptom though is this:  After a long drive the car is shut off for 20 minutes and allowed to heat soak it starts back up like it is flooded, you have to open the throttle or it will just crank, once you open the throttle it will start but blow a lot of black carb smoke.  its like the carb leaks down after a drive?  I dont think it is a float issue because it runs so good.

I spoke with a friend who has the same setup, and same concern.

[48ford]

I had the same problem on the Mach-l,
I put a insulater under the carb and the problem went away.
Hope this helps
Russ&Irene

[enjenjo]

I've had this trouble with mine too. In my case it was the choke set too rich, it would close too fast on cool down. I backed the choke off a couple notches, and cured the problem. It worked for me. This was on two different cars, a buick 300, and a ford 351. the only other issue I have had is hard starting after setting for an extended period, several days or more. That may be related to the first problem.

[Dave]

same thing on my 34 and now on my 32. takes a bit of cranking to start it after its warm.. Id like to fix mine also

Dave

[Ed ke6bnl]

same thing on my 34 and now on my 32. takes a bit of cranking to start it after its warm.. Id like to fix mine also

Dave

I have notice the same issue on my 1406 on my 327 in my 50 f1 pu.  When it sits for a long time it start in an instant when sitting a short time that would alow heat soak it cranks over a few time to start. Ed ke6bnl

[Glen]

Hey guys, I emailed Edelbrock and got this reply:

"Glen,

You're right; the problem is definitely a heat soak issue. Remember, the
fuel these days isn't too great and will evaporate at the drop of a hat.
Once the engine gets up to operating temperature and is turned off, the
carburetor will heat up and the fuel will begin to boil. It most likely
bubbles out of the boosters and drips down into the intake manifold. The
best solution is to install either a heat insulating gasket, one that not
only separates the carb from the manifold, but also shields the bottom of
the carburetor as well. You can get one from your local parts store or we
sell one, part number 9266. You can also use one of our Phenolic 4-hole
insulators. It provides the best insulation out of the two. Of course, you
can get an insulator anywhere, but ours is part number 8711 should you
decide to purchase ours.

Thank you."

[purplepickup]

I was going to post that my 1406 starts real easy when it's hot and I've got a 1" phenolic spacer but I thought maybe it's partly because I'm not running hood side panels either.  You guys have enclosed engine compartments.  I hope the spacer works for you.  I think throttle response is a little better with the spacer too.

[purplepickup]

========= George,

you running an open spacer or the 4 hole type??

4 hole....I tried an open one but the 4 hole responds better.

[48ford]

Hey guys, I emailed Edelbrock and got this reply:

"Glen,

You're right; the problem is definitely a heat soak issue. Remember, the
fuel these days isn't too great and will evaporate at the drop of a hat.
Once the engine gets up to operating temperature and is turned off, the
carburetor will heat up and the fuel will begin to boil. It most likely
bubbles out of the boosters and drips down into the intake manifold. The
best solution is to install either a heat insulating gasket, one that not
only separates the carb from the manifold, but also shields the bottom of
the carburetor as well. You can get one from your local parts store or we
sell one, part number 9266. You can also use one of our Phenolic 4-hole
insulators. It provides the best insulation out of the two. Of course, you
can get an insulator anywhere, but ours is part number 8711 should you
decide to purchase ours.

Thank you."

This is the one I have,it cured the problem in the Mach-l
Russ

[Sean]

I'm not too impressed with my Edelbrock Carb. Mine has the same hot start problem, plus it has more "Bog" than the stock Qjet I was running before.

[Fat Cat]

I'm not too impressed with my Edelbrock Carb. Mine has the same hot start problem, plus it has more "Bog" than the stock Qjet I was running before.

Have you tried rejetting it?

[purplepickup]

I'm not too impressed with my Edelbrock Carb. Mine has the same hot start problem, plus it has more "Bog" than the stock Qjet I was running before.

You can definitely tune that bog out of it.  You might need different jets, metering rods and springs but if you follow the tuning procedure in your manual you can cover about any engine combination.  Actually, they're easy to tune once you understand how it operates and the manual explains it real good.  If you don't have the manual it's on their website too.

[Sean]

I think I kept the Manual somewhere. I did read about the tuning procedure, but from what I understood the top has to come off to change the secondarys, and thats where the Bog is. It runs crisp and responsive on the primarys.

Mine not only starts hard when its Hot, it also takes some finesse to get it started when its Cold. Full choke until it fires, then I have to back the choke off instantly to keep it running. If I don't get the choke in the right position immediately, it dies and I have to repeat the process. Usually takes 3 or 4 tries before I can get it to idle.

I guess I have just been spoiled with the Qjets. Pump it twice and turn the key....

[Dave]

Hey guys, I emailed Edelbrock and got this reply:

"Glen,

You're right; the problem is definitely a heat soak issue. Remember, the
fuel these days isn't too great and will evaporate at the drop of a hat.
Once the engine gets up to operating temperature and is turned off, the
carburetor will heat up and the fuel will begin to boil. It most likely
bubbles out of the boosters and drips down into the intake manifold. The
best solution is to install either a heat insulating gasket, one that not
only separates the carb from the manifold, but also shields the bottom of
the carburetor as well. You can get one from your local parts store or we
sell one, part number 9266. You can also use one of our Phenolic 4-hole
insulators. It provides the best insulation out of the two. Of course, you
can get an insulator anywhere, but ours is part number 8711 should you
decide to purchase ours.

Thank you."

Just put the 8711 heat insulator on the 32 and it didnt do a thing for it. Still starts the same way same as hte old 30 and 34..  :evil: They aint cheap either..
@#$%%^^
Dave

[Pope Downunder]

>>>I guess I have just been spoiled with the Qjets. Pump it twice and turn the key....

I reckon you'll get better economy and driveability with the Qjet.

My 283 has the 500cfm Edelbrock 4-bbl.  That stumble is common. We eventually tuned the stumble out, but at the expense of economy.  I think this is partly because the engine is mechanically ill, and doesn't generate good vacuum.  I wondered at the time whether it could be caused by the '2-step' metering rods.  A lot of the old Carter rods were '3-step', I seem to recall.  I assume these interchange, so next go at it, I'll give that a try.  At this stage, I don't plan on touching it, as the new motor is going together, and I want to fit that over winter.  I'm sure the new motor will throw-out the current 'compromised' calibration.

Having said all that, if I had a good Qjet, I'd stick that on in preference.