VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1937-1945 fuel system problems

I have to dump gas into the carburetor on cold starts.
Driving up or down a hill stalls out the engine.
My 38 has a Carter W-1. It's probably the 420s, but maybe the 391s.
My car has sat in the garage, not started, for the last two years. The mechanic who got it started a month ago said the points were gapped too wide. He tells me that my having to prime the carb is from using poor quality gas. So, I filled up with premium, I think 93 octane, but I still stall out.
What's wrong with my car? Is the carb float stuck? Or is it all gunked up from sitting idle? What do I clean, and with what?

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


good reading

Thanks, but I already had that bookmarked. Here's a more condensed version, on ID'ing carbs:
http://www.chevytalk.org/fusionbb/showtopic.php?tid/159480/

But I still need to know why I'm stalling, why do I have to prime the carb, and how can I rectify those issues.

The carb is probably gunked up from old gas. The accelerator pump is also probably dried up. Get a good quality carb kit, take it apart and soak it in a can of carb dip. Then wash it with hot water and blow it good and dry. Take pictures as you take it apart. They will help going back together. Take your time and make sure to follow the directions. A service manual can help you also.

Thanks, that was a help.

GB,

Whatever the problem, I don't think that higher octane gasoline will make any difference.

Charlie

I wish you would tell my mechanic that. He is pretty firmly convinced.
I have to think the carb cleaning is a better idea. I'm just a litle leery of doing that, or at least a rebuild scares me. I actually bought a kit, but I have just held onto it. I rebuilt a carb once, a 2 bbl. Rochester, in the mid-70's. But that one only had a handful of parts. This Carter rebuild kit has maybe 18 little copper gaskets and o-rings. Putting all that stuff in correctly just looks like a car wreck in slow motion.

It's not really hard. Just follow the instructions in the kit and it will go good. There will also be a diagram of the carb. in the kit.

Thanks for the vote of confidence. Looks like that's what I have to do, because no one here will rebuild a carb. I'm not about to send it off. I think I'll let my wife be the photographer.
Thanks everybody, for the help, as usual. Hope I can repay some day.
Kyle

First, I know nothing!

If it were me, and it ain't, I would be looking at the fuel pump. The diaphram could be bad from sitting so long and from ethanol in the fuel. If so, the pump could furnish enough fuel to run a bit while pumping fuel into your oil pan, thining your oil.

I've seen a lot of good engines destroyed by leaking fuel pump diaphrams. The fuel pump is the first thing I rebuild or replace on a car that has been sitting. It is like antifreeze, darned cheap insurance against ruining an engine.

To me, your symptoms sound more like fuel supply starvation than a bad carb. One thing for sure, (as has been said) higher octane fuel isn't gonna change anything.

Just my 2 cents (and I've been wrong sooo many times!).

Good luck - - -

Glovebox, So you have not been able to drive your car regularly for two years, and you don't feel you have the skill to rebuild a carburetor, which many of us don't. Do you know the condition of your fuel tank, fuel lines, and fuel pump? If you can not answer the previous question don't assume rebuilding the carburetor will solve your problems.

Drain your gas tank and have it professionally cleaned or buy a new tank if you are not 100% aware of its condition. Blow out your gas line with compressed air. Check your fuel pump for contamination and rebuild it or buy a new one if it shows any deterioration, especially if the finger that rests on the cam shows wear. Also, have your carburetor professionally rebuilt by a national rebuilder.

Gaither's comments are relevant. I assume most of us in the hobby need to bite the bullet and spend a lot of money, occasionally, to maintain our cars. Do something special for yourself and plan doing that for the Holiday or New Year.

Best of luck, Mike

P.S I use a video camera to disassemble my car and its parts. I even narrate it as I do the work.

Hey, Gaither, is there a way to stop short of replacing the fuel pump? I mean, can I disconnect the gas line and see if gas spurts out? If it does, that means it's working fine, right, that it's not the weak link in my fuel chain?
Or can I disassemble it and clean it? And how could I tell if the diaphragm is serviceable?
I installed the pump brand new, but that was maybe 3 years ago, before the car stopped running. I just looked, and the Chevs 40s rebuild kit is more than twice what I paid for this fuel pump. The ebay version is better, but still $5 more for a kit than what the pump itself cost me.
So, again, does a disconnect of the fuel line answer the question about the pump's staying right where it is? Or a disassembly and inspection?

Hey, Mike, I think I will start working from the gas fill spout forward.
So, 1st question: am I OK to do that, but spreading the different aspects over some time? If I start with cleaning the gas tank, can I then reinstall it and run the car without ruining the clean tank? Nothing can run backward into the tank, right?
2nd, who cleans gas tanks? I found another site where they suggested a radiator rebuild shop could do this and clean up the tank like brand new. Then they said to coat it, I guess so the problem doesn't repeat. Or do I do the cleaning myself? I found an Eastwood site, where they sell a kit.
Thanks for your help. I do agree that I have to treat the entire fuel system as the problem, until I find out a component is safe.

You can't go on what I think/say. What do I know?

If it were me, I wouldn't gamble my engine on anything less than a new diaphram. Guessing (to save a buck) if the diaphram is not leaking fuel into the pan is something I never do. Yeah, I've discarded a few good fuel pumps being too careful over the years. But, I've never burned bearings being too careful.

"To each his own".

Good luck

fair enough

If you would like to have your gas tank cleaned you could do it yourself by just draining it and seeing what comes out. If it has no contaminants in it then you should be okay. If it has already been repaired with a do it your self kit or at a professional shop like Gas Tank Renu (there is one in Ravenna and another in Planesville, Ohio)then you still might have a problem because of a breakdown in the material used. If you think this is the original tank, or find contaminants in the tank your best bet is too just replace the tank. A new tank on ebay for a 38 costs $214. It is well worth the piece of mind from a reliability stand point. You should also know that most gas tank and fuel line damage occurs from a buildup of rust on the inside caused by water condensation.

One of the first things I did when I bought my 41 in 2003 was replace its original gas tank and lines. I assumed that these 60 year old parts might not be reliable.

You asked Gaither about a method to test your fuel pump on your car. To do that just unhook the fuel line at the carburebtor put the end in a glass bottle and turn the car over with the starter. You do not need the ignition on. You should be able to see the gas filling up the bottle. The gas should have no contaminants in it, if everything in the gas line and tank is okay. The starter should be able to be run for at least 15-20 seconds with out it overheating. You could do this multiple times with out hurting anything. You might discharge the battery, but just hook it back up to a battery charger or tender.

You indicated that three years ago you replaced your fuel pump so it should be okay if the filter in it is not full of contaminants. Check the filter to be sure. If you are getting gas in the engine oil then it will thin the oil and you can feel it on the dip stick and also smell it. If you are suspicious of your fuel pump take it off and inspect it. Look for wear on its finger(rocker arm). If the rocker arm on its wear side is not perfectly flat then a lack of lubrication, or poor part quality is evident. Gas in the oil will cause excessive wear on the rocker arm and cam shaft that it rides on. The wear on the arm will show up as a round indentation in the arm.

The problem with rebuilding a carburetor is mostly lack of experience. It is fairly easy to take apart everything until after the float is removed. The tricky part comes in reseating the accelerator pump, removing any of the brass passage plugs, adjusting the metering rod, and setting the float level. Removing any screw on the carburetor should be done with the largest tipped screwdriver that will fit the screw. You can usually tell a rebuilt carb by the condition of its screws. They look damaged from using small tipped screwdrivers that slip, or disfigure the screw groove, when you attempt to turn the screw. To win the screw battle you need good leverage, the right screw driver, and a well lubricated screw. I would soak the carb in used transmission fluid or even a closed bottle of gas overnight. Getting even a minute bit of lubricant under the screw head is favorable. The next thing is to put the carb in a vise or position where you can put a lot of pressure on the screw head. This could even mean having a helper push the screwdriver down with all the muscle they have while you use a Crescent Wrench to gently turn the screw driver. A lot of the time you will hear a popping sound as the screw lets loose.

A lot of carb rebuild kits are made for several different carbs so they have extra parts that you will not need. Maybe, you might want to choose to not remove any of the passage screws so you will not need any of the copper washers. You might just want to clean everything in gas, use an air compressor to blow things out, and replace only the accelerator pump, float needle and seat, float spring, bowl cover gasket, and manifold/carburetor gasket. You will set the float level and not adjust the metering rod which requires a special gauge. If this solves your problem then you may be happy with only a partial rebuild of your carburetor.

If you decide to tackle rebuilding your carb. let us know I and others will be glad to help you with more tips. Good luck, Mike

All well and good. However, personally I would never trust a fuel pump on a car that had been sitting a lengthy time simply because it would pump a reasonable amount of fuel.

In many cases, a leaky diaphram will pump fuel quite nicely - while it leaks fuel into the oil pan. OK, I'm a hardhead. Sure, the pump might be OK. But, to me, it isn't worth the risk of melting an engine. Compare the cost of a pump to the cost of a ruined engine.

"To each his own" - - -

This is an example of a poorly lubricated fuel pump arm. The arm should be perfectly straight and show little indication of surface wear.

The pump is only 3 years old. It might be in perfect shape but it would be easy to inspect it.

Mike, thanks so much for the detailed response, esp. the info on testing the fuel pump. I will clean the gas tank myself, I think probably even if the gas is clean when I unhook to line. And it sounds like I have a better than even chance on the carb rebuild.