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1964 olds 98, 394 fuel problems

My mechanic has replaced the fuel pump with an electric one, the carb has been rebuilt, he cleaned out the gas tank, pressure tested the fuel lines, replaced the ones he felt neede it. The car ran well for about 59 miles. Then it wouldn’t start after sitting for a couple of days. My son says there is no gas going into the filter. The pump comes on and you can hear it working. But no gas gets into the filter or the carb. Gas put into the carb makes it fire. What else can we try?

I assume the carburetor is a Rochester Quadra-Jet 4 barrel. These carbs are all pretty much the same, so find a Q-jet at a junk yard or on eBay and carefully take it apart…Find a book that deals with rebuilding Q-jets…learn how they work…After you can successfully take apart and put back together your learning carburetor without bending or breaking anything, you are ready to tackle the one on your car…

In the meantime, you can try this. Disconnect the fuel line from the carburetor. You will need 2 wrenches, a 9/16 for the fuel line and I believe a 7/8 for the inlet fitting which also contains a small fuel filter…With the line disconnected and the engine cool, briefly turn on the ignition and see if the electric pump causes fuel to flow from the open end of the fuel line…Be quick about this, you don’t want gasoline everywhere…If gasoline is being pumped, remove that inlet fitting from the carb (carefully) and examine the fuel filter inside it… Is it plugged up? Clean it or replace it…Now re-install the fitting taking extra care not to cross-thread it, connect the fuel line, and again turn on the key. Inspect for leaks. No leaks? It should now start…

Where on the car is the electric pump installed? Why was it installed?

If you’ve got no gas getting to the (presumably underhood) filter you’ve found your problem. Check the fuel line both upstream and downstream of the electric pump. If you’ve got no fuel at the tank side of the pump your mechanic willl need to take another shot at cleaning the tank (and the pickup).

Incidentally, why not begin at the beginning and tell us how this electric pump business all started now, instead of a little bit at a time in thirty or forty posts, since it will save so much time.

I drove this old beast for a short time, maybe about 300 miles. ONe day it just quit on me. It wasn’t getting gas. So, long long story short, it has had its own manual fuel pump rebuilt 2x, same problem. It would come out of the shop, run for about 10 miles and then no fuel again. It did vapor lock last summer, put cold water on the fuel pump and was able to drive it to another shop. He had the carb rebuilt. It would run idling in the lot, then when you drive it, it stops getting fuel. So, he took it back, dropped the gas tank, cleaned it out, cleaned out and replaced a few fuel lines. Still it would only stay running in idle so he finally gave up and installed an electric fuel pump. He installed a new voltage regulator. I drove from the shop to the walmart and got a bigger battery. It did fine for approximately 100 miles. My son drove it and let the gasoline get low. When I tried to start it, it will not get gas. We put gas in the tank, put on a new coil. The fuel pump works as we can hear it running. But no gas to the filter. They are in the process of trying to begin at the new fuel pump to see if the gas is being pumped. The original mechanic could not determine the cause of the fuel delivery problem. Unless he has lied about cleaning the tank and lines, which I really don’t feel he has, there doesn’t seem to be a whole lot of other things that can go wrong from pump to carb. So, since getting this car, I have put in a new ( original part from salvage) ignition, sent the fuel pump to MA to be rebuilt twice, sent the carb to MA to be rebuilt, had the tank cleaned, fuel lines cleaned and bad ones replaced, new voltage regulator, battery and coil. When it runs it runs like a champ. The motor sounds awesome, looses a bit of oil around the place where you put it in, but is a good old car. I just need for it to get gas.

What kind of gas cap is on it? The original should have a pinhole for breathing. Any chance the fuel pump is trying to pull a vacuum on the tank due to the wrong cap or the pinhole being plugged up?

Where is the pump located in relation to the tank? It should be as low as possible.

Has there been any debris in the new pump when removed? The pumps usually have an intake screen in them and these can be easily clogged. From the sound of it this does not appear to be the case; just throwing it out there.

I don’t know if this means anything but I have always put in premium unleaded and octane booster as the car is supposed to have ethyl gasoline.

The mechanic did drill a small hole in the gas cap before finally installing the new electric pump. The pump appears to be next to the tank so it should be in the right place. He is a young guy and most likely not used to working on the old dudes. But surely he knew that. It was a professional shop.
My son did plug a hole in the gas tank when this happened the very first time before the professional mechanic got it. Is there a chance the tank needs a pin hole in it as well?

Okay, we checked the pump. It pumped all the way into the line behind the front wheel. I was shaking the line so that he could find where it cam up into the engine area. Apparently, there was a vapor lock or something in the line as now it pumps to the carb and runs. Maybe this is the problem the whole time? How can I avoid this from happening again?

The pump may be next to the tank but where is it located in relation to the fuel level in the tank?
The pump should be located (preferably) lower than the bottom of the tank or as near that as possible.

If it’s located midway or something like that it could be the pump is going dry at times due to fuel slosh (when fuel is low) or it’s losing it’s prime and having trouble sucking gasoline back up instead of having that constant siphon effect when the pump is below the tank level. Think of a water well pump.