VCCA Home Forums TECHNICAL - 1945 AND NEWER 1946-1948 1946 won't idle

Apparently your carburetor is not a 1946 as 1941 and later had the rectangular accelerator pump shaft. Earlier W-1 carbs had the round accelerator pump shaft. There are other differences depending on the actual application year.

It is also best to have another clear plastic fuel filter near the gas tank! That would be the first one to show signs of any contamination! You can never have to many fuel filters!
Rory

That is not exactly true. Too many fuel filters will tend to cause a gas flow restriction, especially when they become contaminated. Ideally, there should be a filter in the fuel pump and one either by the gas tank or by the carburetor, but not three filters in line.

Thanks, chipper. Well this just gets more and more interesting !!! What do I look for to tell me what year this crazy thing is anyhow ? Goodness knows what has been done to this thing in 71 years !!

This site is very helpful when identifying W-1 carbs;

http://www.thecarburetorshop.com/CarterChevroletW1.htm

Wow !!! Thanks ! At first glance, mine seems to be a 1938 or 1939 model. The people I bought the car from bought it in 1977...so it was 31 years old when they got it. He wrote down for me everything they did to it...no mention of anything about the carburetor.....so it must have been replaced , I am guessing, before they bought it. Who knows what previous owners did ?? LOL

All in all it still sould run and idle OK with an earlier carburetor.
The 1939 carb. will run richer at speed than a 1941. Also the low speed jet has a very tiny opening and almost must be removed for cleaning.
The throttle bore in a 1939 is 1 7/16" and 1 1/2" for 1941 and up. The 1941 and up also has an angle cut tube that you can see when the air cleaner is removed-in the center of the air horn.

Understood...sure once I get it figured out, ( cleaned, rebuilt, or replaced ) it should purr like a kitten as it did in the past. Correct...this carb does not have the tube in the air horn. Thx Chevgene and all of you fine people. Will let you know the results. Merry Christmas to you all...enjoy the day and your family time !!

Clement,

If you decide to rebuild your carburetor do a SEARCH of past posts for info. Also use the internet and the variety of manuals available to understand what is involved in a rebuild. I recommend making a video of the steps you use in removing the carb from your engine and dismantling the carb so you can correctly reassemble it.

Once you identify what carb is correct for your year I would look for the best source of a rebuilt one or a business that would rebuild yours. I would shy away from major part suppliers like Chevs of the 40's, Kanter. etc. that know little about carbs.

Do realize that a perfectly rebuilt carb may not be your problem, but in about a half an hour you could have the carb off your car and apart to check in the bowl for sediment and do a general inspection of its condition.

You may not know how to disassemble your carb. Why not buy one off of ebay and take it apart? 1941. ... Carter carb.

Here is a sample of some posts on this topic: Carter W - 1 carburetor tune up

Good luck, Mike

I would suggest you find a correct 1941-1948 carburetor rather than investing time and money in the one you have.

I agree. I had a 41 carb on my 37 and in ran perfect.

Thank you all again. I am tending toward purchasing a correct year carb. for my 1946. Your insight and suggestions are fabulous. I will do my research first though.

You did not mention HOW you know the intake gasket to cylinder head is "good".

Set the idle speed a "bit" higher to keep the engine running.

Take a propane torch, open the valve ..... BUT DO NOT LIGHT THE TORCH.

With the engine running AND the propane valve open, direct the nozzle of the propane torch between the intake and cylinder head, going from front of engine to rear of engine, by firewall.

If the RPM increases at any given point, with the propane test, the fast idle indicates a leak between the intake manifold and cylinder head.

If you decide to buy a replacement it might be worthwhile contacting Doyle Stokes. His contact info is listed in the Generator and Distributor classified ad section.
Good luck!

Thanks again experts !

Also, I misspoke with an incorrect term several posts back.....I meant to say the carburetor INSULATER, ( on mine it is a plastic piece between the carburetor and manifold ) seems to be good.....I said the manifold gaskets.....I was wrong in saying manifold gaskets, my apologies. It is in the teens here this week....pretty cold, and my garage is not heated. I have not checked yet taking the wiper hose off . Will update soon. Thanks

Just installed a rebuilt carburetor on it...same thing as before.....won't idle, when you push the choke in all the way it dies...Even when warmed up you have to pull choke out all the way or it won't start. I checked the operation of choke before I put air cleaner on. I am really hating this car...I have no idea what is wrong and no idea what to do now.

IF THE PROBLEM IS NOT THE REBUILT CRBURETOR (I SAID IF) you have a massive vacuum leak. Manifold to head possible.

You might want to take the car to your local mechanic and have him diagnose and repair the problem.

Is the vacuum cylinder for the vacuum gear shift hooked up" Is the vacuum cylinder hose (under the car) leaking? off? or?
There is a Y connction on the side of the intake manifold with one small hose running to the wiper motor and a metal tube runnig down to the rubber hose that is connected to the vacuum cylinder. If vacuum s assist had been removed/disconnected the line or hose may have been plugged and "plug" fell out or?

Thanks...will check vacuum lines, etc tomorrow....supposed to be 55 degrees here !!! Vacuum shift disconnected many years ago. I am so frustrated and stumped....thanks all. Driving me nuts...and yes, there is a old time mechanic shop 2 blocks from me.....might end up taking it there !!

That might be a good idea. With their diagnostic equipment they can probably find the issue right away and then repair it for you as well.

From a safety standpoint, a clear plastic or glass fuel filter is dangerous. The NSRA (National Street Rod Association) Safety Inspection Program won't pass a car with either one in the fuel system. The reasoning being they can be easily broken. Under the hood if it comes loose or is improperly mounted and comes in contact with something that can melt or break the filter, instant engine fire. If it's mounted under the car a rock or road debris can be thrown up by a tire and break the housing. May not cause a fire but I'm guessing the fuel running out will cause the car to slow or stall which if it happens in traffic can be dangerous. On my '46 Fleetmaster I have a metal in-line filter by the carb and another mounted on the frame rail in front of the rear axle and carry a spare. There not that more expensive than the plastic ones, and give you a greater piece of mind.

Thank you !! Ok..here is the latest.....The vacuum shift was removed many years ago.....the fitting on the manifold has 2 " ports"....1 is plugged very tightly ( the one that used to go to the vacuum shift ), the other has the wiper hose on that. I tightened every exhaust/intake manifold bolt...each 1 was 1/4 to 1/2 or a little more loose. Started car...ran for several minutes.....as soon as I pushed the choke in it just dies. Restarted several times , doing the same thing ( and I have to pull out choke each time ) and same results. It Will NOT idle !! Am I correct to think my next course of action would be to install new correct intake/exhaust manifold gaskets ? how difficult is this ? Thank you. BTW...I am a VCCA member...# 50675...updated my profile...maybe didn't do it right ?? My number and the logo doesn't show up ? !

The intake and exhaust manifolds are bolted together so will be removed as a unit.
The removing is easy enough but the difficult part is installing due to the alignment rings that line up the intake ports - manifold to head. I usually leave the carburetor installed and the exhaust pipe. and support the weight with a wire attached to the radiator support rod. Just unbolt and swing out the manifold.
Is the idle speed screw set up to keep the engine running at idle speed. Also the idle mixture screw (on left side) should be turned in and after bottoming out (don't turn in with too much force) turned out 1 1/2 turns and after enine is run and warmed-up fine tune for best idle.
To check the intake for leaks get the engine running and squirt oil around the intake to head connections. If leaking (that bad) it should cuuse the exhaust to smoke and run better because it is sucking in the oil.