(video update)More Carb trouble possibly? ??

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The installation manual says 199r-7948-5 if that helps.

I guess I'm going to buy new plugs and if it's too much hassle im going to have the store give me a new carb. only 2 1/2 weeks old and haven't ran it much.

 
Okay that looks like a 4160 with non adjustable floats, that carb is calibrated to run at 6 PSI fuel pressure max. If you are making more than that you will need fuel pressure regulator. Check fuel pressure and go from there. Good luck.

 
You should be able to get a reading, I have a feeling your pressure is a couple PSI over what it should be. I know Edelbrocks dont like more than 6 PSI with 5.5 being ideal. Yours being a holley I really dont how much of an effect it will have. Keep us posted.

 
Well like I said it ran great even moved it around. Couple days later I started it up again and did great. One possibility I'm thinking about is I had a glass filter in line to the Carb but its only a screen and not a paper element. Maybe somehow some trash in the line from pump to Carb got by the screen and making the float not work properly causing it to overload the engine with fuel. Not saying it isn't a fuel.pressure problem but it seemed to run great when I first took it out the box and bolted it on and ran it for quite a while. I would think if it had to much pressure it would have made it apparent at that time.

Thanks for the help I may just get a new Carb I have a 90 day warranty so I could just get another one and put a good real filter in line.

 
Well I got home took off the Carb and when I drained it nasty orange fuel came out the secondary bowl while clean clear fuel came out the primary bowl. Maybe moisture got to the fuel somehow from sitting that hot humid week. I'm taking it back to the parts store tomorrow to get a new one being under warranty. Going to pick up some new plugs while I'm at it and start over again.

 
You need to figure out where that nasty orange fuel came from or you'll just have another carb messed up real soon. The secondary bowl fuel can only get contaminated from one place unless the car was sitting in the rain hood up and no air filter and that is from the fuel feed line. You are running an external fuel source to the old pump thru the old line to the new carb. I have to believe your problem is located in that small section of the fuel system.

I personally disagree with the decision to take the carb back without some particular evidence of fault in the carb. Pull the secondary fuel bowl, clean it our, clean the filters, replace or at least clean and verify that the fuel pump and line are all in good shape. Just swapping it isn't going to teach you anything, nor is it likely to fix the problem-not to mention, now someone is going to get that carb with nasty orange fuel in it and wonder why their car doesn't run right.

 
I returned it as defective. I agree that my problem is in that section so I got new Carb on and bypassing all old crap. Plus I added a actual filter instead just that screen glass one even though I cleaned it and now running 2 filters. Getting ready to fire up and see what happens.

 
Well there's still a problem..no change. They gave me 18mm plugs so I couldn't change them. My engine takes the small 5/8 plugs which seems to me like this 302 is not original to the car. I think the plugs are just so fouled that some aren't firing like they should. Guess I will have to wait until tomorrow.

 
Well there's still a problem..no change. They gave me 18mm plugs so I couldn't change them. My engine takes the small 5/8 plugs which seems to me like this 302 is not original to the car. I think the plugs are just so fouled that some aren't firing like they should. Guess I will have to wait until tomorrow.
Sounds like you're going through similar problems , my car has the 14mm appx 5/8 plugs so is either a later motor or one w/ replaced heads & intake manifold .

Read some of my olds posts on vacuum leaks , spark plugs , carb adjustment, etc lots of good info from members posted there.

 
I'm going to get the correct plugs today. The plugs say #26 and the part store gave me #45. I think the plugs became so fouled some aren't firing. I usually only have about 1 1/2 hour after work before it gets dark to work on it so i didn't have time to test all 8 of them. It's not flooding the intake anymore though so i guess that's a good sign. fuel is super clean now. this has really made my mind spin. My buddy told me to check timing but this engine idled great and revved up like it wanted to come out the engine bay. Thats when i said ok now it runs good I will get my brakes working, so i waited while the hot weather passed a week later it started and i moved it about 10 feet and it died. that was all she wrote after that. Then it became super flooded and wont start. pulled the plugs to dry them out to no avail. My wife got tired of me cursing and told me "just buy a brand new engine" ha ha.

 
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here is a video of the engine running fine after i put on the new carb before i drove it. as you can see it ran fine before!

http://www.youtube.com/watch?v=FQa5scUTN0Q
I think at least part of the problem may be you don't have the choke hooked up and therefore it isn't opening causing it to load up. When you put the new plugs in wire the choke open and see if that helps.

 
Choke is connected now that was mainly just a first time I put it on. Just referencing that I know it ran OK like that. Now I get hardly anything but a sputter. Just got my new auto lite #26 I'm going to put in when I get off work.

 
It ran fine under no load. When you add a load, vacuum drops quickly and the carb will have to have fuel added through the accelerator pump circuit or it will sputter, flat spot, sometimes even die.

I would recommend that whenever a carb is replaced, that the float/fuel level be verified, that idle mixture screws be adjusted for maximum vacuum and smoothest idle, that accelerator pump operation be verified visually. Your choke must be open to test properly. An engine draws more vacuum with the choke closed which improves atomization from the idle circuit and transition slots.

IIRC the other big change was you wired up the choke. You may need to factor that into your diagnoses

 
It ran fine under no load. When you add a load, vacuum drops quickly and the carb will have to have fuel added through the accelerator pump circuit or it will sputter, flat spot, sometimes even die.

I would recommend that whenever a carb is replaced, that the float/fuel level be verified, that idle mixture screws be adjusted for maximum vacuum and smoothest idle, that accelerator pump operation be verified visually. Your choke must be open to test properly. An engine draws more vacuum with the choke closed which improves atomization from the idle circuit and transition slots.

IIRC the other big change was you wired up the choke. You may need to factor that into your diagnoses
Thanks for the info. My Carb has non adjustable floats. I can't get it to run even under no load right now. Just got home, going to install fresh plugs and see if there's any difference.

 
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