OK, I just bolted on a Carter AFB Comp. 4-barrel carb on my 360. Well, today I went out to mess with my manual choke, because it isnt working. Thats another question actually- when I pull my manual choke out on the carb, it doesnt work- well, it works, I mean I pull the ****, and the plate closes on the carb. On my stock 2 brl carb I had, I would always use the choke in the mornings, when the engine was cold and it would roar to life. I am having trouble getting this one to go in the cold- any ideas? But the real problem I just noticed is that my air filter is burnt. I have the Edelbrock one, its pretty low profile, and sorta triangular. It has a foam element, and the portion directly above the barrels on the carb is, well, burnt away. A hole about half fist size is starring me in the face- why? Do I need to adjust how rich/lean the carb is running? If I am sitting in idle and I really bash it, sometimes it gives a small backfire noise more from the carb than anywhere else and the engine almost stops, then kicks up and hauls ***. I have only had this backfire problem once or twice, seems to happen when the engine is rather colder. Please help with either one- very confused.
Tristin

 

> A hole about half fist size is starring me in the face- why?

I have the same filter. When the carb backfires, even though you might not hear it, it melts a hole in the foam. A fist sized hole you can see through means you had a backfire AND a fire. If it is melted and you can not see through it, junk it, since the melted part is like having a piece of plastic wrap covering the carb.

What you can do is stick part of a sock, cut open to lay flat, over it for the time being as a quick and dirty air filter. This works because the foam gets sucked over the cage and the sock will conform to the hole as long as it is not too big.

Using a vacuum gauge, see how much of a difference you experience without the filter and then with the filter. Once I put the filter on I lose about 3# of manifold vacuum and it drops the idle. I am not sure if this is because I have the breather and pcv piped into the air cleaner. It would be interesting to know your experience.

 

If your carb catches on fire, crank over the engine. It will suck out the flames. Check out your timing.

 

Thanks guys but I dont think I have got to quiet what I am looking for. If, by "accident", I bash it while its not warm yet, it seems to give me the click backfire. Its not the engine backfire, thats happened and I know that noise. This one is a weak one- just like a clicky poof- I know, great description. I am thinking it has to do with how rich/lean I am running this carb. But, to adjust this or check this- I need to start the truck! I am having some real trouble with it when its cold. I know its not the battery or the starter since both are brand new- a month old. It turns over really good- so strong. But it just wont get going, and the manual choke does its job- it closes tight but it doesnt help- so I beg one of you to help me! Any ideas?
Thanks
Tristin

 

> This one is a weak one- just like a clicky poof- I know,
> great description. I am thinking it has to do with how rich/lean
> I am running this carb

Yes, I know exactly what you mean, it is a backfire through the carb. I have watched it without the air cleaner on. Sounds sort of like a small whoose/exhale sound than a sharp backfire sound. The sound is not loud, but, the gas is hot enough to melt the foam. With a regular metal air cleaner and paper filter you probably would not even notice it.

My solution was to change the timing and dwell. I now have it so once warmed up, I can just lean in the truck with the choke out and crank it once and it fires up like EFI. I have a manual choke and no fast idle solenoid, I am just using the throttle stop and have mine set at 850 rpms when warm.

This is working off manifold vacuum instead of carb vacuum. This advances the timing on my truck to almost 34 degrees at idle. Not ideal and I know its too much and I have to recurve the distributor.

But, I think the backfire problem was not enough advance at idle. It was much better with 12 degrees base timing (vs.6) running off carb. vac., but, just not good enough.

I am going for a test ride after letting it sit all night in an hour or so.

 

Thanks, at least you know what I am talking about hahah even with that great description. I will reset the timing today most likely, I did it not all that long ago but maybe its off again. But the main problem now still stands- why wont the beast start? It seems that my manual choke isnt doing what it is meant to do- I have a new starter and battery, so I am GUESSING it has to do with the carb, but could it be something else? Please help me out here
Tristin

 

Not being an expert by any means on carbs ... Your carb. works by vacuum and atomizing the air. If your throttle plates do not close and open correctly you can not create a vacuum to atomize the fuel (or to suck it out of the pasage ways) so it gets sucked into the manifold as a liquid instead of a vapor, so it will not ignite.

 

I have the same problem with carb backfire on a 360 with an Edelbrock 1406 and that little triangular air filter. I'm swapping it for a paper element since I'm tired of acquring replacement elements for this one. I've changed to a Mallory Unilite electronic ignition system and I've got the timing set right where it's supposed to be. I've even tried retarding it a few degrees and I get the same problem. It happens whether or not the engine is warm; it's just whenever I really load it up (i.e. try to go up a hill in 3rd at low speeds). But I know you're really concerned about the truck not starting up.

 

 

I've just purchased my '67. It has been my first really stock truck I've had in a long while. It is really hard to get running in the cold mornings. It's bone stock with all factory pieces still attached(even the hot air tube from the exh. manifold). I have found that I basically have to pull the choke, pump it once, crank and let it die. This goes on a few times till it finally will let me pump the throttle a bit to keep it running. I have the choke high idle cam turned up a bit(not sure, no tach yet). It will finally catch and stay running after a couple tries. It will not let me rev it up(usually pops thru the carb) till it runs a minute. The pop in the carb is basically a lean out condition. I have not been able to really poke around much yet(way too cold for that). I know I can't let the choke plate be closed too much for too long or it will basicallly flood itself from the lack of oxygen(it chugs and misfires). That is why I set the high idle up more so I can leave it run faster without the plate closed.

Larry

1967 F100 352/c6
1969 F100 428CJ/4 spd
1959 B model Mack
and a few hot rod FORD cars too