Hello again, my rally gauge pack had new motors put in so the needles needed to be placed back on. I ran the car out of gas in a flat drive way and placed the needle back on right over the E with key on. The thought process was ill start to sweat when it gets close to E and fill up. However in an emergency situation i would have a bit of gas to keep driving on as needle moves past last mark. I went and filled it up and needle goes over top the F and stops (perfect). I run it down during the week and fill up by 1/8 tank left mark and i get 15 gallons to F. Again awesome i got 5 gallons left therabouts..... Well the problem happenend yesterday going up a small hill with 1/8 tank and she stalls out because no fuel gettin to carb. Well luckily the station was 500ft away up the hill so i grab some gas and put it in the tank. She absolutly would not start till i put all 5 gallons in to get it to 1/2 tank! She ran fine after that but it seemed excessive to need the level that high. Anyone that seen the inside of these things maybe know whats goin on? Are there no baffles in this original tank? Maybe pickup is known to sit high? If nothin else whats it take to drop the tank so I can check it out ? Is that fuel line hard to get detached from the tank for the drop?
There are no baffles that I've ever seen. Dropping the tank is pretty easy if its near empty. If it has a few gallons it gets stupid unstable on the floor jack as the gas moves around and upsets the balance
I made a tutorial about fuel gauges here- http://www.v8buick.com/index.php?threads/fuel-gauge-and-sender-operation-and-diagnosis.330220/
Awesome, thanks for the info guys. I should be able to go over my setup to reaffirm things are working as intended
Wanted to update this since I discovered what my problem was. But firstly Mark you were absolutly right about the stupid amount of instability in dropping that tank! I had it run till it quit in my driveway and thought it burned it all out of the tank but even then there was a little left in it and that going about and the width of a STEEL tank really made it want to go haphazard in a second on my floor jack but i got it. So turns out my problem after testing line resistance, connectivity and other things I learned that 1. There are no baffles inside a stock for certain as has be said. No doubt making cornering and hill climbing somthing that can be chance takin when low on gas. Modern fuel injected cars with baffles and sumps have spoiled me on aomthing that was no doubt common knowledge back when everyone drove cars like this 2 the tank sending unit had been replaced and on the pickup that goes into the gas it was 1/4 inch shorter than the replacement I ordered and also had a plastic barrel type strainer that had fallen off into the tank at some point. 3 the sender would have flat spots in the resistance it would read and would say 45ohms but stay as the lever continued to drop until suddenly it would read the correct 15 ohms to where i now had lever. It was not consistant in a spot and would happen all over the range of movement and not for the samet length of time. Th new one constantly changes with movement and is smooth with the lever's travel rate. All three of these different problems no doubt caused the car to quit that day. Sloshed back fuel, shorter pickup, strainer gone in a dirty old tank and finally a buggered up signal from sending unit (thanks buick64203 for thread link for testing components it helped a lot). I got a correct new tank and sending unit with matting and some new straps. When the weather gets warm in a little while I'll be cruising without worry.
