QuestionQUESTION: Hello Dick, I have just finished replacing the gas tank tank, fuel lines, fuel and oil pumps, water pump and carburetor on my 1966 Thunderbird. However when I attempt to start it it runs over nicely but will not start. I pulled the fuel line from the carburetor and tried to start it again with the fuel in a container. After cranking the engine I checked the container for gas. I found none. I then checked the in-line fuel filter and it was dry. I removed the bowl from the fuel pump and there was gas in it. Do you have any ideas (I'm sure you do)why I'm not getting any gas to the carburetor?
ANSWER: It isn't clear to me what happened to the gas that was in the container. If you had it connected to the carburetor inlet, and the gas disappeared, it has gone into the intake manifold while you were cranking, and is now diluting the oil in the crankcase. To verify that, pull the dip stick and smell it. If it smells of gasoline, do not crank the engine anymore until you drain the contaminated oil out of the pan and change the oil filter. Trying to start the engine with fuel in the crankcase can cause a dangerous fire or even an explosion!
If this is what happened, the carburetor is in serious trouble - the gas should only have run into the carburetor in the quantity required to fill the float bowl - any more would flood the engine. The probable trouble with the carburetor is a stuck needle valve.
If you had it the gas container connected somewhere else, tell me about it and I'll try to dope out what happened.
The fuel filter location is also something I need to know - is it in the line between the fuel pump and the carburetor, as it was when the car was new, or has it been installed somewhere else?
I think your next step, after you get the oil dilution problem solved, is to disconnect all fuel sources from the engine and try to start the engine by putting 1 tablespoon of fuel down into the top front of the carburetor, where the choke flap is. Then crank the engine - it should start immediately, even if only for a few seconds. If it does, you now know your starting problem is definitely lack of fuel coming through. If it does not start, your problem is in the ignition system or is mechanical in nature, so sort that all out before you go back to the fuel system mysteries.
Once you have done all those things, get back to me with your answers and results and we'll figure out what to do next.
Dick
---------- FOLLOW-UP ----------
QUESTION: Hi Dick, The container was empty, no gas got from the fuel pump to the container. This is a new carburetor (edelbrock) replacing the old original. I did try to start the car with starter fluid and got nothing. The fuel filter is between the carburetor and the fuel pump and is as dry as the day I got it. When I replaced the fuel pump, the shop manual said to make sure that I have the arm on top of the eccentric. The arm went into place without any problem since I cant see the eccentric so I feel the arm is in the proper place.
AnswerOK, now I understand part of what you did. You put the container where it would catch any fuel that came through the fuel pump and filter - do I have that right?
I had assumed that you used the old car starting trick of connecting a container of gas to the carburetor inlet, and holding it up high enough to gravity feed gas into the carburetor - sort of an IV bottle approach to getting a car running, or at least to diagnose a starting problem.
Now that I understand better, it seems you have at least two problems, and they appear to be independent. One is that your engine didn't start even with starting fluid - and trying that eliminates any concern about fuel supply - your engine isn't starting for some other reason.
But the problem you asked me about is lack of fuel coming through the fuel pump, so I'll tackle that first.
The reason your new fuel pump isn't doing its job is one of the following possiblities:
1. The fuel line is full of air and is not delivering fuel to the pump inlet. To check for this, remove the gas gap and apply a very low pressure to the tank fill pipe, by either blowing into it with a vacuum cleaner that can have its hoses reversed to provide a low pressure volume of air, or by using a normal air compressor set to 5 PSI or less, and sealing around the filler pipe inlet with a rag so as to provide enough air to propel gasoline through the line to the front of the car. Remove the fuel line from the fuel pump inlet while you do this, to catch the fuel and so that you can see when the line is full of fuel.
2. The fuel pump is not installed correctly, in that the actuating arm is not being operated by the fuel pump eccentric (or plunger - depending on which engine you have). To investigate this, remove the fuel pump from the engine and look into the hole with a good light to see the actuating device. When you install the pump, you should feel considerable spring pressure against the pump arm, strong enough that you have difficulty getting the mounting bolts to start into their holes. If you didn't notice this when you installed the pump, I think the pump probably isn't engaging the drive mechanism.
3. The pump may be defective. When you have it out in your hands, operate the lever with your hand, and with your third hand, block the inlet fitting with your finger. You should feel strong vacuum against your finger when you operate the pump arm. Also, block the outlet fitting with your finger - you should feel pressure against your finger when you operate the pump. If either of these things doesn't happen the pump is not working.
4. The filter may be blocked, or installed backwards. Remove it and see if the fuel comes out the pump outlet without the filter present.
When you get the fuel flowing properly, we'll tackle why your engine isn't starting - but this is enough for now (I've got 8 other questions waiting for me, so let me get to them - I'll wait to hear back from you before I do more on your problem).
Dick
