My 77 w/ a 460 @ carter AFB 8867 is giving me fits. A few weeks ago, it died on me, I popped the hood, smelled gas, tried to start it, it would not, and when I let off the starter, a big fog of fuel shot out of the carb as the truck made a deiseling type sound. Took the air filter off, and it was soaked inside. I drained the fuel going into the carb (have a glass filter set up and it was more full than usual), and rapped on the side of the bowl. Went to get starter fluid and left it alone for about 20 minutes. Got it started.

The other day, it was stumbling about 500 feet after I made a right turn (like at an intersection). I would drop it in neutral and run it out and it would clear up. I did get a little water in the tank, and I suspected that to be the culprit.

I go to start it later that afternoon, nothing. Its acting the same as the other night, only I can never get it to clear, and start.

A couple of times the next day I eventually get it to start, but after a few minutes, it goes rough, I blip the throttle and it immediately dies.

One time I blipped the throttle as soon as it started and it died the same way.

So I took the carb off and the intake had a pool of fuel.

I took the top of the carb off, cleaned the float hinge pin, needle and seat, bowl, shot carb cleaner into every hole I could find on it. I pulled and cleaned every part I could in that top part, and everything looks good. The floats are brass and do not appear to have any leaks.



So I let it sit overnight, the pool in the manifold evaporates off, and I put it all back together, and same thing.

I checked the vaccuum advance, appears to be fine.


So it dawned on me. I would assume the fuel pump would have some sort of pressure release set to maintain a certain pressure? Could it be possible that it had taken a digger? I replaced the fuel pump about a year ago, and it is refilling the line after I drain it. So I got to thinking that maybe this pressure release is stuck, and overriding the floats attempts to close off the fuel supply?

Is this notion completely out there or am I on to something.

Any other suggestions?

I have started looking around for rebuild kits, and this particular carb does not seem to be supported any more, the guy I talked to said he would have to call edelbrok tech support and see if the can help me.


thanks,

ackus

 

It is possible that you have too much fuel pressure. Possibly building up too much tank pressure from it not properly venting too.
I would replace the pump first, since they are under $20. Did you check the actual float level when you had the top off?

This will be moved to the EFI/Carb forum since it is not 73-79 specific.
Thanks,
Jimmy

 

ackusackus,
From the sound of your memo, there is too much fuel entering the carb. Did you notice this when you removed the top of the carb? If the bowl has too much gas in it, although rare, it can be because the fuel pressure is to high, or that the float is out of adjustment. Placing a gage in the line will let you know if the pump is over producing.

It has been a while since I took one of these old carbs apart, but as I remember there was some sort of spring attached to the float on certain models. I am not certain if this spring holds the float down, or assists in lifting it up. This may sound a bit basic, but did you check the seat on your needle valve? Sometimes lime deposits get in the valve and keep it from closing properly. I usually check these by blowing air through the fuel line, going into the carb, then lifting the float to see if it shuts the air off when the float get to the correct fuel height.

Please write back and let me know what you find.
Thanks,
John24255

 

Thanks for the replies. I had a vacation in the middle of all this, and just got back to tackling this again. I did not check the float levels. I don't know how, and I don't know what they are suppose to measure. I have been able to find absolutely ZERO documentation on this sucker. I am going to call edelbrock in the AM and see if they can help me with documentation. I am also in the process of removing the fuel pump (soaking a stuck fastner) and will replace that tomorrow.

The valves in the float mechanism do have springs in them. I soaked all the parts in carb cleaner and wiped them down. They did dirty up the rag, but there was no visible damage or large chunks of crud.

My hope and dream at this point is to resolve this immediate problem with a new fuel pump, and get the specs and start saving for a new carb.