Thread: issues with the Edelbrock 1406

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My '57 Willys CJ5 has a 283 SBC. A little background on the powertrain. The engine has been rebuilt and has 1300-ish miles on it now. Th rest of the drive train is stock (rebuilt) with a 3 speed T90A tranny, Dana 18 T-case, rear Dana 44 with 5.38 gears and front with a Dana 25 5.38 gears and both with powerlocks. The carb is an edelbrock 1406 (electric choke) with a performer intake manifold and 305 heads.

1) I was having some issues initially with hot starts. The engine had to crank a while before it would start. I narrowed it down to heat from the intake to the carb causing boil over of fuel (especially with the ethanol content). I used an edelbrock heat gasket (some issues with vacuum leaks but fixed) which worked a little with the starting issue (at hot). I eventually went to an aluminum spacer but I still have some issue, especially now with the hotter temps. I have found that if I can get the electric fan on (if engine temp is hot enough to trigger it) and let it run for a minute, then the engine usually starts ok except for a burst of smoke (almost like flooded). Any suggestions? Would a phenolic spacer be better? The intake is a dual plane but the current spacer is an open spread bore. Does that matter since the intake is a dual plane?

2) The engine runs well at idle and take off in first. However, when accelerating in 2nd and 3rd, there is a hesitation during the acceleration. eventually it evens out and runs well. The carb has the same metering rods it came with in the package. I got the Edelbrock due to its out of box and run setup. It is big enough for the job at hand.

Thanks,
Paul

We run the same carbs on both my 27 and my Son Don's 23. We only had that problem one time. We got back from a long drive one 95 degree day and his T started cutting out. We felt both carbs and they were smoking hot, so we figured the fuel boiled. Strangely enough, I have exactlly the same 2 x 4 setup on my 27 and when I felt mine that day the carbs were cool. We are going to add two of those phenolic spacers to his carbs if the problem reoccurs. I think part of the reason his carbs were hot and mine were cold is because his intake is highly polished aluminum and mine is satin. Perhaps the shine was reflecting the heat back up to the carb bases? That is the only reason I can even think of why his is hotter than mine. Once his car cooled off it fired right up and ran like normal.

You might also try some of that covering that goes over the fuel lines to keep the temps down.

Don

Originally Posted by md85

Would a phenolic spacer be better? The intake is a dual plane but the current spacer is an open spread bore. Does that matter since the intake is a dual plane?
Thanks,
Paul

Yes, a phenolic spacer would be better, and as Don said some use a pair of them. Heat transfers through your aluminum very fast, whereas phenolic is a fibrous material that insulates. The open spread bore configuration of the spacer is not going to matter in your application.
On your stumble in 2nd & 3rd, sounds to me like a slight adjustment in your accelerator pump to increase the shot might fix it.

Aluminum is a great heat transfer medium - so good that many companies use it for radiators. Next, most Performer intakes have an exhaust gas passage though there are versions without. If it has that EGR/exhaust passage set up, that adds even more heat to the carb. The boiling point of gasoline can be as low as 100 degrees F up to 400 degrees all depending on the additives. A phenolic spacer is the first step with a heat shield as a follow up - there are others, ceramic insulated versions, besides the usual and conventional Edelbrock, Holley and Mr Gasket

I had an imperial in here monday for similiar problem, edelbrock starting when hot. I added a fuel pressure gage to the fuel line at the carb and we let the engine idle, i took temp readings with a gun and the engine became stable at 160deg, (heads, carb base and radiator top) and fuel pressure was 5lbish. When we shut the car off i watched fuel pressure (it is trapped at 5lbs between the satisfied float and fuel pump check valve) after a brief time it dropped to 4lbs, later to 3 1/2lbs and so forth. I was watching the effect of the fuel boiling in the bowl and forcing fuel out into the carb, the float would drop and allow more fuel into the bowl and the cycle would repeat itself until there wasn't any fuel left in the line and the fuel in the bowl evaporate.
I took the carb off and saw fuel in the wells of the rear 'gate', the only way fuel can get there is from being forced out of the boosters. I checked the carb for other 'oddities' and ressembled everything and used a mr gasket #98 isloator, a sandwich affair of alternating layers of aluminum and gaskets. We started the engine and got it back to the 160 degrees, the carb was now 30 degrees cooler and when we shut the engine off the fuel pressure stayed constant at 5 lbs.
I wish i had both a phenolic and a wooden spacer to compare but i didn't.

How about a phenolic or wood spacer on top of the aluminum spacer.. to add distance from the intake. I am also going to purchase some heat shield sleeving for the fuel line that runs in the engine bay. I saw wood and phenolic spacers on Jegs..and only phenolic on summit. So it shouldn't matter as far as the divided plenum and the spacer being open or divided right? I will look into adjusting the accelerator pump. I borrowed an inline flow meter to check the pressure of the fuel line..to make sure it isn't over pressurized.

Got the phenolic spacer. Will complete the install tomorrow. Hopefully it will cure the hard hot starts. I am thinking about going with the Holley truck avenger in the near future, for the off road capability. I read it does pretty good with angles, inclines, and nose dives. Right now I have a straight forward Edelbrock, not good for off road use. I saw some videos on the Holley site about tuning it. The avenger is supposed to be a straight out of the box and run, with minimal tuning. I was going with the smallest, 470cfm, for my stock 283 (except headers, performer intake, HEI (Malllory) distributor).

Comparing the 'avenger' to the edelbrock? Bear in mind that the 'avenger' is a holley product and they will tell an absolute lie in a heartbeat. For instance, it is in fact a warmed over 600cfm vacuum secondary carb - they were popular with the dumptrucks with the optional governor - the venturii is the same, the blades are the same etcetcetc but they have mysteriously gained another 50cfm - no big deal, edelbrock did the same with thier 'thunder avs' carbs so i personally don't believe a word any of them say.
All carbs are supposed to be 'out of the box and run' and i find the edelbrock does better than holley, the difference is taht while holley can be a performance carb the edelbrock never will be. If i were serious about off-road stuff i'd have fuel injection, nobodies float/needle&seat/fuel level will perform as well as fuel injection.

thought about EFI..however it looks complicated and not sure which one to go with. The Jeep forums also say EFI is the way to go..no stalling issues.. I have seen some that bolt right up to the stock 4 barrel manifold..