Thread: carb is icing up , let's see your air cleaner ?

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Very briefly,.. i drive a 41 chevy 1/2 ton,
here's my delima : Seems my carb is having a semi-serious icing problem.
327, Edelbrock RPM manifold, w/ edelbrock air cleaner,..
If ithe outside morning temp is 40-50, 'she starts acting like it's running on 5 cylinders. then dies....
Would anyone who has experienced the same problem, post some photos of a remedy / Please,.. kind of shy from driving when I first get up....
jim

Kind of a "is machine plugged in" sort of question. Do you have a choke and is it working?

Art

Thanks,.. Art:
thanks for responding.
1. I had the shop ( where truck is now ) install an eletric choke last Sept.
2, i don't have the heater installed in the cab yet, ( summer project ).
3. The shop thinks the icing occours because of all the exsessive cold air reaching the air cleaner, from all the louvers on the inside of the wheelwells as well as the sides of the hood.
4. On these cold mornings, I always run with the electric fan off. engine temp shows 150-180.
jim

First part of my question is answered. "Does it work" is not. Simple test. With engine cold and key off, lightly depress accelerator pedal (depressed pedals should take Prozac). Pop off air cleaner and verify that choke is closed.

Elaborate a bit on the problem. Is it running crappy from the get go and dies when you start driving? Is it something that occurs after you drive a little bit? In other words, describe the sequence of events.

Art

Great,.your still with me,..
I just be simply driving along normal 50-60 mph ( two lanes, freeway, stop signs ) and then it just quits, ( no power , nothin ), electricty is fine gauges read, fuel pump is activated. I've usually had to let 'her sit, about 20-25 minutes , & she starts right up, & runs fine,.engine bay temp seems to thaw it out... this ( leaves me worried & I just cancel my trip & head back 100 miles very worried no fun,...)

Art, just like a regular daily drive, in the last instance my distance traveled was about 100 miles, was heading down hill, ( POW !..... no power, like the engine just turned off ) the start of my trip is a 30 min. Ferry ride where I have to turn it off for 1/2 hour. i always start off topping off my gas tank ( 10 gal )
this has happened twice so far about 4 months apart. once at nite -in Dec , freaky,
most recenly last Wed. about 10 am , 50-68-degrees, sunny though.
what I don't have is the truck right now to send some photos of the engine bay.
oh yes,
I have a Mallory electronic ignition, The Dec. incident, I had to replace the sensor in the dist. ( $ 150.oo ). if you'd need images I'll go get some..

Probably not the problem, but does your Fuel Tank have a vented Cap? When you take the Fuel Cap off to fill the Tank do you hear a vacuum (sucking sound) from the Tank?

When the Engine stops have you checked to see if you have Spark (Heat Soak?)? Do you have a Fuel Pressure Gauge mounted (or have checked) the Fuel Pressure?

Not to say it can't or doesn't happen, but I haven't heard of an icing problem in a gas enigne above 10 or 20 degrees-realize that when youj drive the Temps go down with speed, but I wonder if there isn't a different explanation here-

hey fourty i have had experience with carbs icing up but when its cold real cold 30 below cold . when the truck stops on ya and you open the hood is the carb literaly icy looking? like a beer mug thas been in the freezer and taken out and actually is icy on the outside. if not i would say not iced up.
water in fuel does funny things also but not till usally around - 10 celcuis 20 f
a v8 makes a lot of heat and can keep a carb pretty ice free
when it quits is there fuel in the car,when you open the ail cleraner and pump the car can you see the accelerator pump put fuel in the engine.
if so problably not fuel.
could be ignition, my dad had a 76 for pickup with a 390 and for the longest time the truck would just quit and sit had fuel but spark went away until it cooled down.
changing the ign module worked but it was weird cause you could switch it back later on and it would run fin and sometime for many miles no problems.

Well, THANKS for all of you chiming in..
I'm preplexed, brief history PRECEEDING , I purchased the truck in Sacramento in Feb 12 , 2005, flew down & Deove the 1200 miles trouble free, MT, Shasta Pass, snow & cold rain. When i returned home, i took the trk to this shop, & basically said, " this is my first chevy, treat it like your grandmother's & tell me what i need to fix? "
few things engine wise,
1. One missing freeze plug,- but no coolant overheating ,,,fixed.
2. radiator leak,- I had the radiator rebuilt due to leaking rebuilt & If memnory serves me 7-8 lb cap.,
3. Chrome thermostat housing blow thru, / no thermostat - replaced with cast iron, added 180. degree thermostat .
4. added automatic choke.
5. truck has ram horn exhaust manifolds. Since posing received a message that they are installing a " starter blanket or wrap.

35Window:
1. no, not a vented cap,
2. no visual sign of any frost, or extreme colld temp.
3. never checked the gas tank for sucking sound..

My secondary reason for ' being in the shop' is to make sure everything underneath was tightened down from the paint shop ( they forgot to tighten the LF wheel, ,,,I got about 3 blocks before I had to stop, i thighted the remaining 5 lugs & promptly headed to Les Schabb to have the wheel checked & replace lug.

Since the hood was off for the 2/1/2 mo. I thought maybe all the accumulated sanding dust, could be a problem & to clean out / check the fuel pump.
big thanks for all of you chiming in...
if I could send you a poster i would.
jim

sounds like a familiar problem i had a few months ago, when my engine would heat up i'd be driving along and all of a sudden she would quit on right after running like a champ.... my problem i found was a coil that was grounding when it started getting hot.... might not be your problem..... but when ignitions go out, it just dies, fuel supply it generally sputters for a few minutes before it dies.....

Say,.. thesals,
i should only be so lucky that ' it sputters ',.. nope mine just flat drops off. ..as in " that's, that's all folks ".....strange the temp is usually around 150-180, w/ electric fan off. but thanks...
jim
, ,..

OK, I'd say icing is out of the picture. The only cars I ever saw ice up at normal temperatures were early Corvairs. We've established that it happens after the engine warms up, but I'm a little confused there. When you first posted, you said, "'she starts acting like it's running on 5 cylinders. then dies..." In your last post you said, " i should only be so lucky that ' it sputters ',.. nope mine just flat drops off. ..as in " that's, that's all folks "" If it does start running weak just before it dies, there's lots of things that could cause that. Have you changed the fuel filter? I had a car that would die when cruising on freeways. Turned out to be fine particals in the fuel tank that would clog the filter. Let it sit for a bit and enough would settle off the filter to allow gas to flow again. Drove me crazy for a while. thesals suggestion of a short at operating temperature is a possibility. When it dies, check one of your spark plug wires for a nice fat spark. Without getting into exotic problems, engines usally stop running because there's no spark or there's no fuel. Figure out which of these it is and go from there. Long distance diagnosis is hard without all the facts.

Begin with spark and if it's there, check to see that the carbs getting fuel.

Art

Art,..
What it feels like is the ' power ' is taken away. The rumble of the 2 cherry bombs sound kind of duddy then silence..., ( not the rich rumble I'm use to hearing..).
I just figured since I had lights, radio, gauges etc, it porbably wasn't the electrical.
And since it has beeb sitting in a bodyshop, with the hood off, bed off , fuel tank disconnected, I'd take it in to have the electrical fuel pump cleaned/ checked, as ell as the carb...
who knows how other people treat your stuff, no one cares about it as much as I do.

cheap insurance,..piece of mind