47 Won't Start - not getting gas?

[47SpcDlx]

I tried Carlas suggestion a slowly poured gas into the carb and the car started.  I then removed the fuel line at the carb and I was pumping gas fine.  When I reinstalled the line the car started. Go figure!

I removed the carb and although it looked perfectly clean on the outside and was rebuilt just a couple of thousand miles ago the inside had a lot of dirt in it.  I cleaned the carb and reinstalled it.

However, I don't want to hook it back up until in can completely clean my fuel system.  The gas in the car is almost two years old.  I put stabile in it but it still looks like varnish so I want to remove all if it and start fresh.

I have another question that I'll start another post on.  I need to know what tool is used to remove the plug in the bottom of the gas tank.  I've removed it before and I think I may have forced a chisel into it and used vice grips or somthing to get it out.

Thanks for all of your input especially to Carla for taking the time to provide a detailed answer.

You guys (and gals) are great.

Steve

[47SpcDlx]

Thanks for the replies.  I plan to try your ideas this weekend and will post the results heres.

Steve

[John Hendricks]

Well said,Carla.  Now if i could only find a glass coke bottle.........

[Carla]

Hi, Steve,

The quickest and easiest way to 'troubleshoot' a fuel problem, when there is no known other problem with the engine, is to simply have the air cleaner off, and 'trickle' some fresh gasoline into the carb.

The easiest way, which I've done for years and years when needed, is to use a small glass bottle, such as a coke or soda bottle. Rinse out the bottle, dry it, fill it about 1/4 to 1/3 full of fresh gasoline, and hold it over the carbie with your thumb over the opening. Have the ignition 'on', and have a helper kick the starter whilst  you hold the throttle rod about half throttle with your other hand.

By moving your thumb ever so slightly, you allow a very thin trickle of fresh gasoline into the carbie whilst the engine is cranking. If there are no other engine problems, the engine will fire and run on this thin stream of gasoline, and you can keep the engine running as long as you have patience for, by continuing to feed it 'just enough' fuel........that is, you are acting as a human 'metering system'.

If the engine will run as long as it is fed gasoline this way, you have located the  basic problem as being one of fuel supply, and the tests to further isolate the problem component are obvious.

A good starting point is to have the top off the carbie, and look for a stuck float valve, dirt in the carb, etc., but have a new gasket set on hand before opening up the carbie, as the gaskets will sometimes stick and/or break.

Check fuel supply by taking the fuel line off the carb, holding any suitable container over the end of the line, and cranking the engine with the ignition 'off'. You should see a good stream of fuel with each turn of the engine. If you don't see a good stream of gasoline with each pumping cycle of the pump, then the cause, obviously, is a defective pump, a blockage, or a vacuum leak.

You mention replacing the pump, so an obvious question would be whether the diaphragm is one of the older type which can be attacked by the ingredients in modern 'motor fuel'. 'New old stock' fuel pumps can be problem, in this respect, for which the remedy is to get a replacement diaphragm of materials meant to resist modern fuel additives. Likewise, some 'new old stock' flexible fuel hoses are damaged by modern fuels, so check the flex hose to the pump.

There is one not-so-obvious problem which can be a real nuisance. Over the years, a little bit of rust will form on the steel fuel line which runs along the chassis frame from the tank to the forward cross-member, where it connects to the flexible hose to the fuel pump. A bit of dirt can be trapped between the steel fuel line and the chassis frame, which will hold moisture, and so induce rust. The rust can strike deeply into the thin steel of the line, and create minute pinholes, which allow for a bit of a vacuum leak.

A minute vacuum leak from very tiny pin-holes in the fuel line can mimic the effect of a weak fuel pump.......that is, the pump may deliver just barely enough fuel, or just barely not enough, or do so intermittently. The reason I mention this relative to your car is that sometimes this condition wil be more noticeable after the car has been dormant awhile.

The test for a pin-holed fuel line (or damage to the fittings causing a vacuum leak) is to take the fuel line loose back at the tank, and put a known good vacuum gage on the line, using suitable adaptors. (take the line loose at the pump first, and blow out any fuel in the line, then reconnect) Crank the engine and observe the vacuum on the gage, continuing to crank until the reading no longer rises. Observe whether the vacuum reading drops off quickly when you stop cranking the engine. If it does, you have a leaky fitting or pin-holed fuel line.

Checking for damaged fittings (one of the famous marks of 'gas station mechanics') will be obvious.....any of those fittings, once they have been cross-threaded or the flares scarred, won't hold vacuum. Sometimes you can make an expedient repair with a bit of 'Devcon epoxy', or even a bit of Permatex carefully applied to the internal flare, but its best to replace the fittings.

If the fuel line is pin-holed, it really should be replaced with new line, of course, but its possible to make a serviceable repair by locating the rusty spots, sanding them smooth, and sealing them with a bit of 'Devcon Plastic Steel', or equivalent, epoxy applied to the tube. Structural strength of the line is not an issue, if the epoxy sealant adheres adequately, it will seal any pin-holes. An older technique for that job was to tear a narrow strip of thin cotton cloth, say from an old bed-sheet, saturate the cloth with gasket shellac, and wrap the tubing,  pulling the cloth down firmly and tucking the ends under the previous turn.

Checking out and fixing any fuel system problems are only part of the job, tho, when you have a car which won't start after a bit of storage.......there are quite a few places in the electricals where a bit of corrosion can grow, which can 'add up' to cause a weak spark, so following a good basic 'tune-up procedure' would be a really prudent idea.

One of the best practical investments you can make, for your car, would be to look through internet old book finding resources, and buy yourself copies of a couple of books written by Jack Steele, in the 1946-47 period. The titles are 'How to Find a Short', and 'How to Tune Up Your Automobile', and they don't cost much......maybe $5-$10-ish from a 'rare book seller'....or $3-ish on ebay.

They are intended as 'basic' or 'entry level' material, and do an excellent job of explaining '30's and '40's vintage automotive work, walking a 'newbie' through the basic concepts of electrical and fuel systems, and then into clear, practical instructions for diagnosis and repair of those systems, with examples of the 'everyday work' which came into his shop. One of these days, when-ever I 'get around to it', I plan to see whether those books are still in copyright, if not, I'll have them re-printed, as they are the best and simplest way for anyone with a '30's or '40's vintage car to learn about their cars.

Another minor, but worthwhile bit of 'learning-curve' can be found on the internet, these days.......use Google, or whatever search programme, to find 'Gus Wilson' or the 'Gus Wilson stories'........these were a monthly fiction item from a magazine, about a fictional master mechanic finding and fixing various and sundry obscure mechanical problems. Some of the stories seem a bit silly, by modern standards, and they're hardly good fiction writing, but the mechanical details are accurate.....which, of course, was the point of the stories.

cheers

Carla

[50Plymouth]

When you say "would not start" do you mean didn't want to at first and did after a while with help, or never got it to fire period?

Before checking fuel delivery I'll state the obvious and ask did you check for spark yet? If your shock IS getting to your plugs, and you suspect fuel pump then I'd say go ahead disconnect fuel inlet \ needle&seat adapter at the carb. grab a suitable container to collect fuel safely, and after giving the carb. your favorite starter boost agent at letting the engine run for the brief few seconds check how the fuel delivery is doing. You could always rent or borrow someones fuels fuel pressure gauge.

If the needle & inlet is an issue you can remove that easily w/o digging into carb. assuming your '47 uses the same carb. as my '50.

Ryan

[John Hendricks]

WD 40 makes an excellent starting fluid-it won't blow your gaskets like ether.  Both my truck and pickup do that "no firet" trick on occasion.  It seems to be that the needle valve at the inlet to the carb sticks closed after the gas evaporates from the cARrb resevoir.  at any rate I take the aircleaner off and undo the 4 screws to take the top of the carb off.  Careful u don't tear the gasket.  It is a real pain with the pickup as i have not converted the aircleaner from oil to paper.  sometimes a shot of WD 40 frees up the needle valve with out having to take it out.  Don't drop the pin or the spring!!!!!!!! U don't want to know how i know that.  I seem to have less of a problem since I started putting fuel stabilizer in the gas.  What I really need to do is drive them more often.  The Dodge truck is dismantled for restoration, and I won't even try to start it without first fillling the carb resevoir.

[47SpcDlx]

I have a 47 Special Delux with a 52 6 cyl engine.  The car wound not start this spring, after being very dependable for the last 15 years, and I am just now getting back into looking into the problem.

I think it may be the fuel pump although I replaced it just a couple of years ago and have only put on a couple of hundred miles.  Can someone please tell me how to troubeshoot this issue.

Thank in advance for your help.

Steve