The Stovebolt Site Forums The Shop Area Engine Shop Hard to start

I wanted to get some opinions on an issue I have starting my 54 3100, original engine and carburetor. If the truck sits for several days without being started it becomes very hard to start. It turns over but does not fire at all. I can crank it to the point of running the battery down trying to start it. I recently discovered if I give it a shot of starting fluid it fires right up. Once it has been started, it starts very easy and runs great. As long as I start it at least every other day it fires right up as soon as I touch the starter. I suspect when I leave it sitting the fuel drains out of the carburetor preventing it from starting until I have cranked it enough to get the fuel pressure back up and fuel in the carburetor. It also appears my carburetor is leaking fuel around the gaskets. The side of the carburetor stays wet and down about an inch onto the manifold. It runs so well once it starts I was afraid to touch the carburetor, even to change gaskets if the group thinks it is some other problem.

Are you using the choke properly?
Jerry

My 57 235 is the same way. I plan to put an electric fuel pump on it some day. For now I just keep a little extra gas around to prime it. I've also considered putting a check valve in the fuel line close to the carb but I don't know for sure if that would help.

I have the same problem with my '57 235 if it sits for more than a few days.
Even in warm temperatures, I find that I need to pull the choke all the way out and then it will start right up. I push it all the way in right after it fires.

Matt

I do use the choke. I am pretty sure I do it correctly.

That's how a choke is supposed to be used. Full choke when cold, crank until the engine fires, then push the knob halfway in or a little less to prevent flooding and stalling. A cold engine that starts easily without choking is running WAY too rich. It should not be necessary to pump the gas pedal at all if the choke is working right. If an engine with a completely dry float bowl needs to be cranked for more than 10 seconds, the fuel pump is probably bad. With some gas in the carb, 2-5 seconds of cranking should be all that's required.
Jerry

Do these old carburetors have a filter at the inlet of the carburetor. I see an inline filter on the rubber fuel line

I'm assuming that you have a Rochester B on your '54. It does not have an internal filter, but some have a screen in the main well. The reason I say 'some' is that I don't think that they all had them, and ones that did sometimes had it removed during rebuilding.

Matt

neat truck

yes this is very common, the gas just evaporates out of the carb, It can't drain out, the inlet is at the top of the carburetor. do yourself a favor and throw the starting fluid away, there is no need for it under most any circumstance unless you are trying to start a diesel engine in point barrow alaska. And many reasons not to use it.I have seen many thousands of dollars spent on engines ruined by ether. Get a squeeze bottle with a pointy tip and put some gas into the vent of the carb, not down the throat of the carb.
There may be other issues, but ether is not the answer

brokenhead,

Thanks for the good advice regarding regular use of ether/starter-fluid.

Where is the vent on this carb?

Here's an odd add-on question: what would use to prime an updraft carb (and where would you "shoot" it)?

Thanks,

As far as gas draining out of the carburetor, I am thinking it could be leaking through the gaskets and that explains why the side of the carburetor is staying wet. Thanks for the info on starting fluid. I have only done this 2-3 times. brokenhead asked what I was thinking. Where is the vent?

Most carbs have an angled tube sticking into the air stream above the choke plate. That's the float bowl vent. Squirt 2-3 ounces of gas into that tube and it will put enough fuel into the float chamber for the accelerator pump and all the jets to get liquid gasoline. A good-working fuel pump will fill even a bone dry carburetor in a matter of a few seconds of cranking.
Jerry

I am starting to agree I might have a failing fuel pump. I am starting to have problems with the engine cutting out briefly. No backfire but it will suddenly cut out and then restart. This is most prominent when putting it under a load such as shifting gears. This is random but becoming more frequent.

Test it. Disconnect the fuel line at the carb and crank the engine with the ignition off for a few seconds. You should get a strong squirt of gas into a container within just a couple of turns of the engine. With the engine idling on the gas in the float bowl it should pump at least a pint in 30 seconds into a catch can. If either test shows little or no volume, proceed to testing the outlet pressure and inlet vacuum. Pressure should be 2-4 PSI and should hold for several seconds after engine shutdown. Vacuum should be 10-12 inches of mercury and should also hold for a while. Like Sun used to say, "We test, not guess!"
Jerry

You need to examine exactly where your choke cable puts the choke blade at various positions.
For carburetors available with automatic choke, there is a "vacuum break adjustment" given in the service literature, which is the precise amount the choke is held open by the diaphragm by engine vacuum when the engine starts dead cold. The choke will retract as it heats up, but that setting is fairly critical: too far closed and you get black smoke, too far open and it will stall repeatedly.
IIRC the setting for a "B" is 5/32" from completely closed.

Try this link:

http://www.thecarburetorshop.com/Troubleshooting.htm#Hardstartcold

Jon

I finally got around to testing my fuel problem, or at least trying to. . I took brokenhead's advice and stayed away from the either. I poured gas into the vent tube and tried starting the engine. It turned over but did not fire. I continued playing with the choke and attempting to start it until I ran the battery down. I decided to give the either another try just to get it started. It fired right up. I had to re-think the problem. I could be wrong, but here is my conclusion. The plugs are not firing hot enough to lite the gas but hot enough to lite the either (lower ignition temperature). The question, why? I checked the voltage coming to the coil. Only about 3.4 volts with the engine off. I had about 10.5 coming into the ballast resistor. My ballast resistor has two sides. I switched the wires to the other side. I then had about 10 volts to the coil. I turned the key and the engine fires right up. The voltage going to the coil with the engine running is about 11 volts, 14.4 going into the ballast resistor. It is dropping the voltage some but from what I have read, not enough. I know this is a problem but at least now I know the cause a my hard starts. Not enough fire to the plugs. I am guessing I need to replace the ballast resistor but I have not seen anything where a ballast resistor can go bad and restrict the voltage too much. I have only seen where they go open when bad?

You have a MOPAR ballast resistor. That one was used on some mid-1970's Chrysler products with electronic ignition. You need to buy a ballast resistor for a mid to late 1950's GM product, like maybe a 1959 Chevrolet or Pontiac, etc. V8 or 6 cylinder doesn't matter- - - -they're all the same. With the points closed and the ignition switch turned on, you should get around 9.5-10 volts at the + terminal of the coil. With the engine running, a 4 volt drop across the resistor should be about right- - - -14 volts in, 10-11 volts out is OK.
Jerry

Thanks. I will look for the right ballast resistor.

The voltages you're getting now are very close to right. I'd recommend cutting the connector blades off that provide too much drop just to prevent getting them hooked up again by mistake, and running the resistor you already have, now that you've got the right voltage to the coil.

If you're still running a stomp starter, I'd suggest getting a late model starter switch with the bypass terminal on the side, and running a resistor bypass wire to the coil + terminal for better cold starting performance.
Jerry