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What could cause this?

New condensors are not immune to outright failure. Especially nowadays.
 
You have something floating around in your needle and seat I bet. I had a similar issue. 318 with a 2 barrel that had been sitting since 1980 I did everything you did, tank, lines, pump, rebuilt carb. It has same symptoms as yours but I have electronic ignition. Ended up on a whim one day pulling the needle and seat out by accident when I went to just remove the fuel line from the carb to turn over and check for pressure. Took some B12 and sprayed it all down and blew into it and sure as **** a small piece of crap was in there. Put it all back together and it runs like a frickin top.

Worth a shot bro.
 
Does your dizzy cap have a vent? Ionization of the air occurs under there and can wreak havoc on the ignition system
 
In your video, there is a blue can on the passenger inner fender. Is that a filter or an electric fuel pump?
 
Ok, cleaned the cArb out. Didn't find anything out of the ordinary there. I checked the fuel pressure and it holds steady at 8, use to be 10 when I first put the new pump on. Anyway, it does loose pressure immediately when you cut off the engine. Just drops back to zero almost as fast as I can walk back around the car. I took off the fuel pump and found some gunk sitting in it. I am going to replace it but I don't think that will solve my problem.

The blue canister is a block heater.
 
nuther vote on a fuel problem. Did you clean out your fuel line from the tank,any rubber hoses kinked? New pumps can be bad too.change the fuel filter. Did you reuse the sock filter on the sending unit or new?
 
I doubt this is your problem but once you figure out what the problem is, set your points a bit wider than .017. When I ran a points system, plugs were set at .033 and points were set at .020 and then the tune would 'drive in' over a period of time and would actually last longer. Using the Blue Streak parts and tuning that way, it would last for a year or better. Also, when points run hot, they have a tendency to expand, burn and close up thus shutting things down. You're burning them up it sounds like. Usually, it's too much voltage at the points....
 
1337du0 said:
Ok, cleaned the cArb out. Didn't find anything out of the ordinary there. I checked the fuel pressure and it holds steady at 8, use to be 10 when I first put the new pump on. Anyway, it does loose pressure immediately when you cut off the engine. Just drops back to zero almost as fast as I can walk back around the car. I took off the fuel pump and found some gunk sitting in it. I am going to replace it but I don't think that will solve my problem.

The blue canister is a block heater.
Click to expand...
Interesting... the only other thing that should cause the pressure drop when stopped is a leaky needle & seat in the carb. What fuel pump is this? If a stock type, should be 5-7 psi I do believe. Gotta wonder if this have been overcoming the needle valve and running excess fuel.

Just curious: How often do you use the block heater out there?
 
Everything fuel related is new. I did find gunk in the fuel pump. Used my warranty and am about to put a new one on. I will let you know what happens.

I haven't used the block heater yet, I picked up this car just after winter ended. I doubt I will really use it out here though. Where I am it usually doesn't gett too much colder than 20s and I plan on having this car in the garage anyway.
 
Need to find out where the gunk is coming from.....
 
J
1337du0 said:
Ok, cleaned the cArb out. Didn't find anything out of the ordinary there. I checked the fuel pressure and it holds steady at 8, use to be 10 when I first put the new pump on. Anyway, it does loose pressure immediately when you cut off the engine. Just drops back to zero almost as fast as I can walk back around the car. I took off the fuel pump and found some gunk sitting in it. I am going to replace it but I don't think that will solve my problem.

The blue canister is a block heater.
Click to expand...
8 or 10 lbs fuel pressure? What kind of fuel pump are you running? That's way too much fuel pressure for that carb. It's flooding.
 
blow that fuel sending unit sock off and give it a shot
 
1337du0 said:
I haven't used the block heater yet, I picked up this car just after winter ended. I doubt I will really use it out here though. Where I am it usually doesn't gett too much colder than 20s and I plan on having this car in the garage anyway.
Click to expand...
OK, did not think it got all that cold in Colorodo Springs; just curious.
 
If my fuel pump is only suppose to be running 6 - 7.5 psi, why would it be running higher than that? I put a new one on last night and it was putting out a constant 9.5 psi. Could that be causing my problem?

Also, it solved the issue of loosing psi right after cutting off the engine.
 
OK, well the prior pump sure must have had a shakey outlet valve then. That is something to have fixed; a bad outlet valve can let the output pressure drop.

Excess fuel pressure can overcome the needle valve in the carb inlet and cause excess fuel in the bowl, leading to poor running and killing the engine with excess fuel (rich mixture). Can you borrow another fuel pressure gauge just to double check? Just want to be sure it is not an erroneous gauge. And are you testing the fuel pressure by running the gauge off of a tee in the line to the carb with the engine running? Don't just run the line direct into the gauge only and crank the engine for a reading for an accurate running reading.

What brand is this pump and where did it come from? I would not be totally trustful of chain store pumps.
 
I am running the pressure gauge off of a tee. The fuel pump is an airtex that is only suppose to be pushing 6-7.5 psi. If it is over coming the carb, that may explain why it is acting the way that it is now, but why was I able to drive for days before the issue surfaced?

I'm really starting to run out of ideas here.
 
How's it done since you carb cleaned it all blew it out and replaced the fuel pump? You could regulate it down but u probably need a better pressure gauge
 
just for s&gs, got another carb to swap on?
 
Well, fuel pumps are rated at a certain pressure at a certain flow. It may be that it will put out the higher pressure at a low flow rate like at idle. There are a lot of Airtex models; is this a 6866? If so, it is indeed rated at 6.5-7 psi max pressure by itself. So the high reading is odd or an iaccurate gauge. Would be interesting if you could know the pressure while cruising.

Why did things change? Parts fail; it obviously has something wrong with the fast bleed off of the pressure (assuming the needle is holding) and it got gunk into it somehow. So something has been changing.

With the change in pump, it would be worth some test driving.
 
I can't drive it now. Things seem to have changed after I put the new pump on. The longest it runs is for a minute or two and then just dies completely and spits some fuel up out of the carb. It acts like it is flooding because it won't start right back up but if I wait about 20 - 30 minutes it will do the same thing.

I do know someone that has a messed up carb that works but needs rebuilt. I think we will try it out tomorrow and see what happens. While I have my carb out I may as well take it completely Apart and see what I can find.

Also the fuel pump is the 6866 model.
 
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