autolite 1100 stalling when slowing down or turning

sparkyj

Well-known member
Happy new Year!
I know this is an issue with this Autolite 1100 carb. I want to make sure I have all of the settings correct.

After the car warms up I get a putter-out type of stall at stop lights and more importantly when slowing down for turns. Scary!

I do not have the carb plate hooked up to the heater core line. Is this supposed to prevent the carb from getting too hot? Or is it supposed to warm up the carb? I'm in LA where it is usually pretty warm.
Anyways, just mentioning that. I think I've got the old style distributer as well, the one with the little collar pin on the dizzy shaft to keep the rottor on.

I just had this carb rebuilt this year but the car has been sitting a bit. Any knowledge in this area is greatly appreciated, and any tuning tips as well. This smells like it is running a little rich..

thanks
 
If your car is a stocker you should hook up the carbs heater lines they are to warm up the carb and give better fuel atomization. I would also check the float level to make sure it's not set to high. :nod:
 
Do you know how to set the float level? I don't know how you do it with the carb on. Typically, you take it off, hold it upside down and measure the distance it falls. You bend the tab in or out depending on what you measure.

I live in the LA area close to the Angeles Natl Forest above Pasadena. I don't have a problem with the carb base heater not being hooked up. However, some guys do. It not only keeps the base warm to prevent icing, more importantly, it gives a consistent temperature where the fuel is atomized.

You can set the idle mixture down some too, so that there is not too much gas when you come off idle. The best way to adjust I have found is to use a vacuum gauge. With the vac gauge connected BELOW THE CARB, at the manifold, you tighten the idle fuel mix in with a screwdriver until it just starts to stumble. Then you back it out until you get peak vacuum and then give it another quarter turn. You might have to reset the idle if it runs faster or slower than before. Idle is 700 to 800 rpm in drive.
 
it sounds more like the vacuum can on the distributor is busted, had this happen to me when I had the 1100 and LOM...

quick test... pull vacuum line from carb, blow in line when still connected to distributor, if it can't hold air and leaks, replace canister from napa.


Good luck and let us know!
 
These are all great suggestions. I did bost the idle up a tad. Then I played with the idle mixture screw, in until it stammered then out about 1/4-1/2 turn. The increase in rpm was quite a bit. I have always wondered about that diz. I know this would run better with a new distributer, but the canister...hmm, that sounds like a possibility. The float level I might save for last. It seems to be running a little better. I little jumpy while accelerating. I need to get the vacuum gage an learn how to use it. i know that is going to be the turning point in sussing this WHOLE motor out...

Also this Vacuum windshield wiper box is dead. Maybe there is a pressure loss there?

Thanks guys
Happy new year..
 
Pull all the vac lines that you don't need and plug them. Then do the adjust stuff. Then put them back on. You could plug the wiper vac straight away and find out if you have a leak there. All the lines should be checked out to rule out vac leaks.
 
Late coming into this thread. Maybe you're back on and have found and fixed the issue(s).
First thing I would have asked/checked about would have been:

- Is this 1100 automatic choke or manual?

- Does this 1100 have an anti-stall dashpot on the passenger side of the bowl?

All things having theoretically been adjusted correctly after the first rebuild, and assuming everything was running fine at that point prior to the "sit" (if it's less than a year of sit hard to see how anything would have just come out of adjustment that much) the things I might be prone to think of first would be heat related or vacuum related issues as suggested above.

However, there are things you could check prior to even that to make sure the carb is adjusted properly right off the bat.
If manual choke, check that choke cable is allowing choke valve to open completely on release. If carb has an anti-stall dashpot, adjust according to original manual. Recommend that fast idle and idle mixture are checked and adjusted properly first.

If stalling or sputtering was happening during turns only I'd look straight to the float as the problem source, and I'd check to see if the needle was replaced during the rebuild (the rubber should be pointy to properly stop up the inlet hole, not even slightly rounded or flat), and that the float adjustment was made at least to spec - if not even a touch lower on this particular carb. But you said in OP that it's happening at stoplights, too; so that means possibly something else. Not ruling out the float, but, again, would check a couple easier things first before pulling the upper off for float adjustment, and having to replace a gasket. Is any fuel coming out of the vent hole at the rod above the bowl? Is float original? Replaced or repaired during rebuild?

Summary (in the order I'd do it - all done at temp to eliminate anomalies):
- Check (manual) choke isn't sticking closed
- Check (automatic) choke is getting proper heat feed and shutting off at temp
- Check idle mixture, fast idle, and then anti-stall dashpot adjustments are correct (The first two can be a very touchy balancing act - be patient and get them right before moving on to the dashpot adjustment)(ludwig's suggestion of using a vacuum gauge is a great one that I've never tried, and will definitely have to)
- Check that acceleration pump spacing adjustment is correct per spec using "HI" position for initial, and leaving in "HI" position for road testing*
- Check that the notch on the vent valve rod is in alignment with the edge of it's housing hole while in hot idle position

All of the above are the kinds of "bench" adjustments that can be checked relatively quickly without pulling off the upper body to check the float. If it is, indeed, the float at least you've made sure by ruling out everything else; and such adjustments are good to check as a starting point, anyway.

I don't suspect the float is bad (leak), really, since that would flood the situation and just stay flooded. But then, I always do leak tests on older floats while I have them accessible, anyway, just because it's easy enough to do - in the moment. And if you do ultimately go inside to check I'd recommend it as usual.

Be interested to know what you finally find, in the end.

*The Manual recommends setting the acceleration pump arm pin in the "LO" position if the engine is running in anything above 50 degrees F, or above 5000 ft altitude. Initial adjustments should be performed in the "HI" position, of course, but I've always found that testing beyond initial adjustments also works out better in the "HI" position as well. Also, I live in the Mojave Desert and have temps somewhat similar to yours depending on the present weather, and I still run in the "HI" position year round with no problems. I might not be saving very much fuel, economically, but this setup likes its gasoline. (Might be different after an engine rebuild, but that's a bridge to come later.) Recommend testing both ("LO" and "HI") to see what runs best for you, of course.
 
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