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Discussion Starter #1
Found something strange. I just replaced the upper radiator hose and started the engine to check for leaks. Took the engine to 2000 rpms a couple times to see if that would cause any leaks. While I was doing that I noticed a weird problem. Every time the engine got to around 1600 rpms it would stumble and then keep going. This is in park, too. When I drove it around the block, it didn't stumble at 1600 (but does stumble off idle every now and then).

:confused:

Also, if I brake too hard the car wants to die (rpms go down to around 500), and when I let off the gas to slow down a bit and then give it some gas to accelerate again, it stumbles before it goes. I'm having a lot of problems with this carb and the problem is I don't know how to do anything on Edelbrocks. When I had the Holley I could at least do the basics like changing the float level, but how do you do that on an Edelbrock? There's no sight plugs, and it looks like I'd have to bend the float to change the settings? :eek:

Carb is an Edelbrock Thunder Series AVS 650.

If you guys need any more info, just ask.

EDIT: I can also get a video of the 1600 rpm stumble if it would help.

Thanks in advance.
Matt
 

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Is there a point when moving the throttle that it starts to sputter and will stay that way or does it stumble and then run fine? I wonder if the transfer slots are dirty?
 

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Here I went on edelbrocks website and got this off there manual section. They have pictures on there to help you out. Go to carbs. Then performer manuals. You do have to bend that tab. Good Luck :)

To properly adjust the floats in the EPS carburetor, two procedures must be followed. First, invert the airhorn cover (Figure 8) holding the airhorn gasket in place. There should be 7/16" between the airhorn gasket and the top of the outer end of the float. To adjust the float level, bend the float lever until the recommended level is attained. DO NOT press the needle into the seat when adjusting the float lever. Next, you should check the float drop (Figure 9).
Hold the airhorn upright and let the floats hang down. There should be 1-1/4" ± 1/4" between the airhorn gasket and the top of the outer end of the float. To adjust the float drop, bend the tab on the back until the recommended float drop is attained.
 

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Discussion Starter #5
Hmm, was afraid of that. Thanks, I'll try that tomorrow. :)

Matt
 

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Yeah there is no way around it. You have to bend that tab to adjust it. It kind of sucks but thats the way its gotta be done. Good luck and let us know how it goes. :D
 

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Discussion Starter #7
Well, took it apart and the floats were definitely out of wack. There was maybe 1/4 of clearance where there should have been 7/16", and when the floats hung down there was about 2" instead of the 15/16". :eek:

Seems to be driving better, but it sounds weird at idle. Sounds like there's a tapping/knocking sound. Not like engine knock, though...I'll have to see if there's anything I forgot to hook up or something like that.

I'd like to think that the adjustments are the cure, but the weather suddenly got cold and rainy, so it could be that. :(

Matt
 

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Check your header gaskets. This one time I went threw and adjusted all my roller rockers on the left side and I couldn't get the tapping to go away. Turns out it was just the header bolts were loose and blew my gasket apart. :mad: I'm glad you got it running good. Let me know if the gasket was the problem
 

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also make sure you tune the carb with a vacuum gage. Tune each screw to acheive the best vacuum. Good Luck :D
 
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