Edelbrock accelerater pump

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Airdwayne

Airdwayne

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An someone explain to me the pump system on my 1406. Technically the 1477 kit. All I was able to do was pinch the rubber plunger past the 4 spokes as you might say to swap with the new one in the kit. Used the new check ball and weight as well. I have no pump shot. Only a light dribble. If that really. Unused in the kit is an umbrella looking thing and plastic disc with a hole. Doesn't look like the pump assembly comes apart without possibly breaking the 2 plastic pieces.

It's a used 1406 off craigslist I bought to replace my 4160 for $40 cause the guy switched to a dual feed Holley. I've dipped in carb/ metal cleaner. Barrymans I think. Took the air horn/ top off and nozzle out. Stuck gumout carb cleaner in and sprayed. Bubbled back to the bowl. Pumped by hand and bubbles in the bowl. Put it all back together and pumped by hand. Still nothing. Did I miss something? I replaced every part I took out. The instructions never go into detail on the pump assembly.

I thought I would try an eddy on my eddy manifold and so far, even with this issue, I'm glad. Idles far more even, starts right up.

Thanks in advance!
 
You had plenty of fuel in the pump area of course?
One little trick I can tell you is to put a small metal shaft (screw, machine bolt, whatever) and tap the weight on top of the ball to be sure the ball is seating.

You can test how it seals by removing the fuel from the carb bowls and fill the pump cavity to see if it leaks down.
Basically the ball is supposed to work as a one way valve and only let fuel in via the hole under the ball.
Otherwise the spring on the pump shaft can be threaded (unscrewed) off the shaft and the new one threaded on.
as long as you dont bend it all up it will work fine.
 
I removed the top again to verify float level. Adjusted the drop to specs. Checked the length of the pump assembly rod to air horn. Getting more amount just not steady stream. This week I will buy a new assembly. If that don't work, back in the dip followed by streams of carb cleaner and compressed air.
 
Probably your plunger did nt seat properly due to the installation technique, or there is dirt in the well. Carb cleaner will not do it any good....if there is dirt in there, it need to be cleaned out; carb cleaner and dip will just push it down in and will be hard on the pump rubber (and any soft seals).

BTW the ball is there to prevent air from being sucked back into the pump shot cavity rather than fuel, as the pump retracts after each use. The ball and weight rod need to move freely, and the ball needs to seat well as noted by Trailbeast; otherwise, it sucks in air. Refer here: [ame]http://www.edelbrock.com/automotive/misc/tech-center/install/1000/1404_manual.pdf[/ame]
 
nm9stheham said:
Probably your plunger did nt seat properly due to the installation technique, or there is dirt in the well. Carb cleaner will not do it any good....if there is dirt in there, it need to be cleaned out; carb cleaner and dip will just push it down in and will be hard on the pump rubber (and any soft seals).

BTW the ball is there to prevent air from being sucked back into the pump shot cavity rather than fuel, as the pump retracts after each use. The ball and weight rod need to move freely, and the ball needs to seat well as noted by Trailbeast; otherwise, it sucks in air. Refer here: http://www.edelbrock.com/automotive/misc/tech-center/install/1000/1404_manual.pdf
Click to expand...

Sorry man, but that isn't the case with the check ball.
If the check ball doesn't seal the pump will push the gas back into the fuel bowls instead of out the squirter horns.
 
Hey T-beast,

Check out the diagram on page 8 and the description on pgs 7-8 of the supplied Edlebrock manual link. It describes the ball and weight as being on the discharge side of the pump and the diagram shows it clearly; the 'lip seal' is the inlet side 1-way valve. I assume that Edelbrock is properly describing their carb operation....in their manual.....

I am familiar with Holley's doing as you say....

Regards, Mark B.
 
nm9stheham said:
Hey T-beast,

Check out the diagram on page 8 and the description on pgs 7-8 of the supplied Edlebrock manual link. It describes the ball and weight as being on the discharge side of the pump and the diagram shows it clearly; the 'lip seal' is the inlet side 1-way valve. I assume that Edelbrock is properly describing their carb operation....in their manual.....

I am familiar with Holley's doing as you say....

Regards, Mark B.
Click to expand...

No ****, you are right the Eddie does do it that way.
I think that is the first carb I have ever seen put the check valve downstream.
Sorry about that Mark.
 
nm9stheham said:
Nothing to be sorry about....heck, I had to check the manual to be sure!
Click to expand...

Then this kind of verifies that it could ONLY be his pump (as long as the ball is seating anyway) and the float level and pump actuating rod is right.
 
All I know is I'm going to borrow a compressor from work and blow it out like crazy. To me it's like the pump assembly doesn't quite clear the break between bowl and pump cavity. And fuel level is low even with float set. I'm hoping there's just junk in there and will blow out.
 
If you mean that the fuel level in the bowl is low with the float set, then the float setting needs to be changed! Not sue if you mean in the bowl or...????
 
Yeah the fuel level in the bowl seems low. Maybe an inch or so full. Coming from holleys I'm relatively new to these types of carb so I have no idea where full with the top cover off is in general. When I get home ill remover the air horn and try to post a picture.
 
OK, 'twould be interesting to see, but ultimately we can all look at pix all day long and not be able to say for sure if the level was 1/6" low or high or what; that much difference will usually have an effect. I'd reccommned that you just read up on the manual's procedure for setting the float (p 14) and check it. If it IS way out, show us a pix so we can all say "How the he** was that thing running?!?" LOL
 
After going over the manual, primarily the secondary side of things since it's mechanical secondaries, could it possibly be I have yet to create enough air flow through the secondaries to draw fuel? Since the car has only been sitting, revving in park, and not having a load on it. I've got pump squirt now and using the plain step up spring since it has 20 or so inches of vacuum at idle in park and doesn't really drop in gear.
 
[ame]http://youtu.be/4XDvj5jDBDE[/ame] a short clip. Reminds me of a modified at local speedway.
 
If you very slowly open the throttle, will it rev up at all? If not, it is almost like the main wells are totally gummed/plugged up. This would restrict idle fuel for any off-idle operation. Since this is off CL, and used, seems like it would be subject ot any amount of crud in the carb.

When you said you checked the float drop, did you also check the float height from the cover with it inverted as per the manual?
 
Yeah I checked with the cover inverted. Multiple times. I'm pretty sure if I go slow it will increase as normal. Not 100% sure. Been too busy at work to mess with it. Either way I bought a new kit and accelerator pump and will leave it to soak maybe over night. But I've been hearing mixed reviews of barrymans chem dip. Followed by a long round of compressed air. Am I right about using the heavier step up springs for my 20 vacuum at idle in park and idle in gear?
 
I assume that you are totally disassembling the carb when cleaning? If not, then I would not be expecting to get it fully clean (assumign that is the issue). With this being off of CL, I would be stripping it ALL apart to clean, and inspecting for cracks, loose venturi mounting, bent/binding metering rods and linkages, etc.....the seller could have sold for problems other than he stated.....gee, that never happens, right? And there was a recent thread here about a casting/machining issue in the base of one of these carbs......

The stronger staging spring makes sense with the higher vacuum readings, but I don't think that is likely the issue; if you are fuly opening the throttle from idle when sitting; the vacuum is dropping below even the lowest staging spring setting, and certainly the stongest one (at 8" Hg) and the metering rod is doing its thing in moving. The way the video sounded, it seems like there is very little extra fuel getting to the engine for the air.

Dumb questions: Are the secondary air valves closed at idle? Have you looked into the secondaries with a mirror while trying this quick throttle opening and seeing if the air valves stay closed? I would expect them to stay closed in this light load condition of opening the throttle when sitting still. And is the einge warmed up when you try this? (Is there a choke on this carb?)

And BTW, I am no expert on these; I am just reading the manual on how it works and applying my Holley and Weber and general carb experiences to try to help. (Carb's work pretty much on the same principles....) Any experienced Edelbrock guys should lend their expertise.....
 
Anything that can be removed is removed prior to a dip. The air valve stays closed when the throttle is moved. I wouldn't think it would open with no load.

I had this same problem when I had the Holley on it. But the Holley would have nice response when idling in park. It would only go into a lean like bog when gradually increasing speed going down the road. Mashing the pedal from a stop would spin the tires. Only seemed to do it when a rolling start.

Current time is between 18 and 20 initial with FBO limiter plate in the 14 degree slot.
 
Update: Im glad to say i no longer face this problem. been reading about an over night soak in Pine Sol so i decided to spend $11 for 2 large bottles of pine sol vs $25-$30 for 3/4 can of Barryman Chem-Dip. New Gasket kit, New Accelerator pump assembly. good, steady stream upon throttle movement.
 
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