I have an Edelbrock 600 (W/electric choke) on a RPM manifold too. The engine is a 68 327 and stock internals (heads were just rebuilt). Lately it seems to want to stall when I drive it around. Example, first start-up is good. Drive it around for a good hour. Stop at a place, starts up, then when I accel/give it gas, it seems to want to stall but then runs fine. Doesn't stall when I'm waiting at a stop sign. What are the tools or info to know that your carb is set to best setting? I just dont know. I mean, I dial in the throttle for a decent idel sound, but that's it. Any info or point me in the right direction would be great. Thanks Ken
I have found that your question is a good one however, it has a thousand answers. I just bought a book on Holley carbs, cuz I don't know squat about them, and it doesn't take long to discover that they are complex. I'm sure that someone will jump my ass about this but, I never realized how many different models Holley has made over the years. I also didn't know that they've been around since about 1906 or something. Anyway, what model do you have and what type of secondaries does it have?
You need to pull the plugs and see if they're black or tan or white. That's the 1st indicator. If it stumbles on accell then it may be as simple as the accellerator pump position. I think there's 2 settings, one for a long duration pump shot and one for a bigger faster (higher volume per stroke) shot. If it idles and drives OK there's probably just 1 or 2 settings to play with. Take a look at the accell pump rod and see what you have. I don't know if there's an online tech manual for em but that'd be worth a search.
read the book that came with the carb buy the kit and start changing things but one change at a time and keep notes on what you did and what the effect is
Aman You're right! Well it's basically a Weber 4 barrel (With Edelbrock name slapped on it). It's a 600 cfm with electric choke. When I first bought it (About 5-6 yrs ago). All I did was install a new Edelbrock RPM instake and the carb and set timming. I screwed the distributator, because it died a couple days later. I was in Riverside at the time and took to a shop that dialed it in for me and was perfect for then on. Now after re-doing my truck (4 years) the engine was gone through and seems to be having these little set backs. Is this carb junk and buy a better carb? What are your thoughts on a good strong 4 barrel carb on the market? Ken
As Aman stated there could be many causes for your problem. The first check on any Holley is your float setting. With the car on level ground pull the sight plug on the side of the float bowl and gas should just start to spill over the edge. If it doesn't - back off the large screw on top of the needle valve and turn the 5/8 nut to the left until gas does start to spill out then tighten the large screw. If gas gushes out of the sight plug when you remove it do the opposite. Until you know the float level is correct any other diagnosis is futile.
I'd check fuel pump pressure and fuel filter....also if you have made any changes in the fuel lines,etc, it could also be vapor lock. And why do people keep giving you tips on Holleys?
I know, but it doesn't really matter, right? All carbs are designed to do the same thing. The fuel lines are new. I fabed stainless steel lines (3/4") All ends to the rubber connections have been double flared. Rubber lines from the tank to the electric fuel pump (Holey) in the middle and from the firewall to the carb. I heard from Dreadman at the Mooneyes show that the after market glass fuel bowls type filters cause Vapor lock. There's no filter, just using it as a visual trouble shooting, fuel is getting to the carb. Anybody else shed some light on this? Ken
Did it have this problem before you made the lines? If it didn't, then look at routing of your lines....make sure they push the fuel uphill (firewall fuel block should be below the float bowl levels) Also check the lines to make sure they don't run near excess heat sources. Fuel may be getting to the carb, but so can air in the lines when driving.
the edelbrock carb is a good carb to use, and easily adjustable. you need to decie whether or not your acceleration problem is due to a rich or a lean pump shot. once you have done that, then you can start adjusting the acceleration system. if you added performance items like a larger cam, etc. then likely your pump is lean. you might also need to change the jets and/or metering rods to get the fuel curve you need.
Ok. is the choke properly adjusted to fully open after warm up? There are 3 positions for accelerator pump. Also Do you have a spring kit for the carb? Any time you change the engine characteristics you will have to redial the carb.The spring kits have 5 differant size springs in them that basically control rich and lean, if that is any part of the problem check into that.It's the 2 phillips or torx screws on top and on either side of the carb.Springs are color coded so you don't mix them up.If none of that works I dunno unless you may have the floats too high
Guilty in having the Fuel filter above the carb, then a rubber line to the carb, see pic. I also have a fuel filter (Incomming)screwed into the electric fuel pump (located by the gas tank). Also, Thanks for everyones input. I'm really not to clued in on engine stuff and need to learn. Thanks Ken
If it doesnt want to stall in stop and go traffic your problem is not going to be the accel pump or fuel mixture, from your description it sounds like you only have this problem after a hot restart, could be the fuel is leaking out of the bowl (which isnt likely as you didnt mention a cold start problem) or perculating. do you have a phenolic spacer between the carb and intake? Larry
Just the plain ole gasket that comes in the Felt pro kit. What is a "phenolic spacer"? Yes it happens when I've been driving for awhile, stop somewhere then it starts up then hit the pedal it kinda hesitates then gets back and drives fine. This hesitation/stalling only happens when I'm hitting the gas pedal too. Again thanks for all the info. I'm going through the carb with the above notes. I need to be more knowledgeable and will do this, this weekend. Ken
phenoilc spacers are a heat absorbing plastic that will help if you are having perculating problems. Sometimes you can tell by looking down the throats and seeing a brownish color.The spacers you can buy in differant thicknesses but if that's your problem a 1 or 2 in. will probably help
I always use a one or two inch spacer under an Edelbrock to avoid heat soak after a short shut down. To set up the carb, you need a vacuum gauge with a hose long enough to put the gauge in the car and go for a ride. Drive the car like you normally would, start out fast enough to keep up with traffic. Record the lowest vacuum level averaged from a half dozen starts. If the answer is seven, put in a set of springs for six. Then set the idle screws for best vacuum setting. Read the book well. Its really easy, if you take the time to understand it.
no filter? five year old carburetor? open it up, clean it out, put new gaskets in it and use a good inline filter
If its "perculating" then float level is too high and overrunning needle and seat. Fuel pressure has to be around 4.5-5.0 PSi. Got that info from the Edelbrock rep... Spoons
Edelbrocks are pretty sensitive to fuel pressure - check that first. They are also sensitive to boiling the fuel (percolation) when shutdown. Unless its on an intake that is isolated from heat, I would use a phenolic spacer.
First, Thanks for all the feed back. Great Info! I'm gonna go through the carb whether it' the problem or not, just so I know. Again Thanks! Viva La HAMB! Ken
I just rebuilt an edelbrock carb for a friend. It was model #1405 (600 cfm,manual choke,non emission). If you find it's an accelerator pump adjustment:1.back out idle speed screw to allow primary throttle valves to seat in the bores. On models 1400,1405,&1406,the pump connector rod goes in the 2nd hole from the top of the pump arm. You have to bend the pump arm to get 17/32 of an inch between the top of the pump shaft and the top of the bowl. On the 1407 model, the pump rod goes in the top hole of the pump arm,but that measurment is 19/32 of an inch between the top of the bowl and the top of the pump shaft.
All right, I don't know if this is allowed, but I;ll post it anyway. The answer is on another board in this thread: http://www.diamondbackengines.com/mainsite/cartersetup.htm also some great carb info here: http://www.moparstyle.net/forums/showthread.php?t=74069 and here http://www.diamondbackengines.com/forums/index.php/topic,68.0.html I didn't write these, a guy named Damon Kuhn did. I can attest to him being one smart SOB, who has tuned countless cars. He doesn't miss much. If you want it running right, follow his directions. DOn't let his forum name fool you, he goes by Fugly, which in the name of his 61 Plymouth Fury Drag car. .......You ever seen one of them run a 9.60?......with AFB's?? anyone who run in the 9's with AFB's has my respect.
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