Bad gas?

[Ron Lowe]

My all stock A ran perfect last time I drove it. It has been resting for 3 months. Drove today and it misses and backfires . You guys think my gas has become bad or should I check for other problems. I forgot to add anything to thr gas when I parked it . Any ideas will be appreciated. Ron

[bambooboy]

if you have clear setiment bowl,check to see if any seperation of the fuel.water is heaviver than gas

[jmeckel]

If you used gas with ethanol it could be full of water, as it will absorb water out of the air. I have had that issue with gas in my tractors. I recommend non-ethanol gas if you can get it in your area.

[fordcoupe]

May be water in fuel with the way the temp is up and down especially if the tank is not full It may be fuel line blocked I would check fuel first then move on to electrical next remove fuel line drain in a clear heavy plastic jar let it set a few minutes you will see water on bottom of jar and you can check fuel Flow at the same time.

[Mitch//pa]

if you feel you have bad gas drain some intt a glass bowl from the carb line.. i doubt you do
or

we test for contaminated gas by lighting a small sample on the concrete floor. if it is mixed with diesel or water etc it will leave an unburned residue..
you might want to start by cleaning and adjusting your points and if that does not help do a systematic diagnosis..

[Jim/GA]

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Originally Posted by Ron Lowe

My all stock A ran perfect last time I drove it. It has been resting for 3 months. Drove today and it misses and backfires . You guys think my gas has become bad or should I check for other problems. I forgot to add anything to thr gas when I parked it . Any ideas will be appreciated. Ron

YES!

I just had this problem with my car (4 month old gas). I had about 1/4 tank and added 5 gallons of fresh on top. Cleared it right up.

I saw it with another car last spring. The guy didn't believe me. We put in fresh fuel and the car ran great again.

So I would sure start there.

[bikejunk]

I have this problem with my very early motorcycles "fresh gas" clears the problem right away.but you have to empty the sediment bowl and the float as well.

[John Stone]

Had a similar problem. Found the main jet had some black goo on the outlet. Car would run but had to open the GAV a lot to get any performance. Snorted and backfired a lot. Cleaned the carb jets and fixed it. Of course it had alcohol gas and had sat for a couple months. Found a place that sells non alcohol gas and that solved the problem.

[ed thibodeau]

My A's set for 6 mo. every winter with E10 gas, and we are in a high humidity area and I have never had a starting or running problem in the spring. In a unheated barn with a concrete floor. I don't know why so many people seem to have a serious problem with the gas. Could it be something else???
Ed.

[Purdy Swoft]

People that don't have problems with ethanol gas after they sit must be getting either fresher ethanol gas or less ethanol content in their gas than we get here. If mine sit for three weeks , they skip and run so poorly that I wouldn't try to drive them . If I couldn't get ethanol free gas, I would have to give up on my model A's weed eater power saw and lawn mower . Additives don't seem to help and when they run on fresh ethanol gas they don't have near as much power or get nearly as many miles to the gallon. Ethanol ruins the rubber parts on my saws and mowers. Ethanol causes the valve stems to get sticky and either causes a miss or loss of compression.

I recommend completely draining the fuel system, clean the fuel filters or replace them. Remove the carburetor and use spray can carburetor cleaner and spray in through all jets and passages in the carburetor. Add fresh ethanol free gas and add marvel mystery oil to the fresh gas and crankcase.The marvel Mystery oil will help clean the valve stems and free up the sticky valves . Move it outside , connect a temporary vacume line to the intake manifold and stick the other end of the temporary vacume line in the bottle of marvel mystery oil When the engine cranks the vacume will draw the mystery oil up the intake manifold and will clean and free the sticky valves. I stood side of the car with the marvel mystery oil bottle in one hand and operated the throttle to keep it running while is sucked up the oil. It will smoke a lot but in a little while it will quit skipping and smooth out. You can then remove the temporary vacume line and reconnect the normal vacume line. You may need to check the spark plugs and clean off any excess oily residue. You should then be good to go. Take it out and run it enough to make sure that the valves get well freed up. This is what I had to do. The carburetor had to be replaced on my weed eater. The gas caps were ruined on my says and I had to use channel lock pliers to remove them. The saws still hesitate and don't want to rev up until they get hot. New or newer cars will get by with ethanol if they are used on a daily basis. It ruined the fuel pump in our tahor and stranded us 100 miles away from home. It cost nearly a thousand dollars to fix it. in a few months the new fuel pump started going out again so we traded it in. The Cadillac SRX that we traded for seems to run good on the ethanol gas. Just our experience with ethanol. I avoid it in my model A's and yard equipment .

[Mike V. Florida]

Try just cleaning the points first and see what happens.

[C26Pinelake]

I do not experience this problem with my cars and I attribute the success to the use of SeaFoam being added to each tankful of gasoline. I look at it as cheap protection for the benefits derived. 1/2 can in each tankful, so about $3.00 a tank full!
Wayne

[Ron Lowe]

Thanks for all the input guys. I'll clean my points and put fresh gas in it. Ron

[Gary Karr]

You might also try cleaning out the jets in your carburetor. If you remove the main and cap jets and soak them in carb cleaner or even lacquer thinner and replace them, you might notice a difference.

[sphanna]

Sometimes we can become so blinded by our agenda to convince others to accept the myth of ethanol not being harmful to fuel systems that the facts backed by experience will not move us. Purdy tells it as it is and has offered some suggestions on how to deal with it. When i can't get gas sans ethanol any more, I may add water to the gas in a container, let it set for a week or so, than drain water off bottom to get gasoline from the top. In the mean time, i will just use it when nothing else is availabe and be sure to use it up.

[sphanna]

Sorry, i was a little harsh with my opinion above. Just read it and i do not like to come across like that.

[Purdy Swoft]

Originally Posted by Mike V. Florida

Try just cleaning the points first and see what happens.

I did check the points first. I thought that the gas would be OK because I had added the additive to prevent problems with alcohol fuel plus Marvel Mystery oil. The problem was the fuel and I am sure of it . We have had problems with our lawn equipment and our previous vehicle as well. The Chevrolet Tahoe was driven quiet a bit every day. The problem was that vehicles with the fuel pump in the tank will fail because the pump is submerged in the ethanol at all times. It doesn't seem to bother the Cadillac yet .

[Tom Wesenberg]

Purdy brought up a good idea to pickle an engine with an updaft carb. Just use a temporary vacuum hose and stick it into a quart of motor oil. Let the engine idle until it smokes a lot from the oil being sucked in, then kill the engine while it's sucking the oil. This will leave a nice oil coating in the engine for long term storage.

On downdraft carbs I just remove the air cleaner lid and pour in the oil while the engine idles, until I see a lot of smoke, then I pour it in quick enough to kill the engine. Remove the keys and the engine should be good for quite a long sleep. Of course it's always best to tape the exhaust pipe closed, to keep out the rodents and humidity.