QuestionQUESTION: when starting car does fine but after running it say 15 miles turn it off and sometimes, will not restart, or runs battery low before it catches thanks bunches
ANSWER: Hi Nanci,
What kind of car is this?
Howard
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QUESTION: Thanks Howard, I am so soory it is a 1976 triump spitfire!!
ANSWER: Hi Nanci,
When a car will spin over but not start when hot and I got many that way in the dealerships I worked in. I had to duplicate the problem and at the time of failure I needed to check for spark at the plugs. You can either pull a plug wire off the spark plug and hold it about an eight of an inch from the plug while someone spins the starter over. If you are not comfortable holding a plug wire like that, you can take a timing light and put it on a plug wire and hold the trigger down and watch the flash of the light. (This must be done while the car is hot and in it's failed mode)
If you have spark at the plugs, take a can of spray starting fluid and spray a little into the intake while someone tries to start the engine. If it starts up with the spray then the problem is fuel related. Starting fluid is available at most any auto parts store.
If you find it to be fuel related, it can be either too little fuel per air or too much fuel per air. It is usually easy to separate the two by trying to start the engine hot and when it will not start, quickly remove all four spark plugs to see if they are wet or dry. If they are wet, it can be a heat soak problem, meaning when you shut off a hot engine the excess heat of the engine and exhaust manifold will will heat up the carburetor so much that it boils the fuel in the float chamber which can't escape so it runs out of the jet and down into the intake manifold and floods the engine.
After setting for a while the raw fuel will vaporize and the engine will then start. This is the case when you run the car until hot and shut it down and quickly try to restart and get a no start. Another problem with heat soak is that the fuel boils in the float chamber and is forced out the jet flooding the engine and after a short time vaporizes and leaves the float chamber empty and then it take quite a long starter spinning for the mechanical fuel pump to refill the float chamber.
There is a simple test you can do at home to test for "Heat Soak" problems. Run the car until hot and quickly stop and open the hood and put an electric house fan on the carburetor side so as to cool the carburetor down. Then try to start the engine when you know it would not normally start. If it starts up without any starter fluid then you know it is a heat soak problem.
Be sure to test for ignition first, Always test fire first then fuel last. In some cases I would run a compression test when hot and in the failed mode first as a tight valve clearance can cause that but that is more rare then fuel and fire problems.
Let me know the results of the tests.
Howard
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QUESTION: Thanks Harold, it will be awhile before I can find someone to look into this, Some one suggested it may be the ethenol in the gas, any take on this? Thanks again nanci
AnswerThe only problem ethanol in gas can cause is that it gives you a little higher octane which allows you to advance the ignition timing a little which gives you a little more horse power and it tends to make the combustion chamber run a little cleaner including the spark plugs. It also tends to absorb small amounts of water that may be in the tank and it tends to make the exhaust burn a little cleaner and it cuts down a little on oil bought from the middle east.
If all of that bothers you, you should not use gas with ethanol in it.
I all fairness to the anti-alternative fuels, ethanol will effect some plastic and rubber parts in the fuel system in older cars.
Read my experience with ethanol as a fuel. http://mg-tri-jag.net/alcohol_fuel.htm
Howard (not Harold)
