Doing bodywork on a friends '51 Chevy Fleetline w/216 and a 3sp. Drove it over to my house and car was running fine. I tried to fire it up next morning and it wouldn't start. No fuel to carb. I replaced the pump and still, no joy. PO had done work on the car, converted to 12v, replaced essentials, etc. The original f/p was probably replaced too. I replaced it with an O'Reillys f/p, just like the one that was on it. Yeah, it's upside down. But this is the way the old one came off and it ran fine! You can clearly see the inlet/outlet ports are marked........... Every f/p I've ever seen was mounted right side up........ If I mounted it right side up, the ports would be on opposite sides, which ain't right. And yes, even mounted upside down the lever is engaged with the cam lobe so it should be pumping yet still no fuel to the carb. I've blown out the lines back to the tank and also to the carb, it has gas and a new filter but not a drop gets to the carb. I'm at a loss!
Air leak between pump and tank? Does fuel gravity drain when pump inlet is disconnected? There is no standard 'right way' to mount pumps, just depends on how they are designed. Cam location, arm shape etc determine up/down position.
The pump is correctly positioned. My Son chased this on a 50. Rusted lines and bad fuel tank was the issue despite new fuel pump being installed.
I'm with Ken, check for an air leak on the suction side. If there is a rubber hose coming from the tank, even a tiny crack or pinhole can let in enough air to cease pumping fuel.
There is gas in the tank. I'm gonna crawl underneath and check for any air leaks, inspect rubber hoses, steel lines/tank, etc. Thanks for the responses!
Remove the inlet line, put your thumb over the inlet fitting on the pump and have someone step on the starter. If the pump is working, you should feel a vacuum against your thumb. If it’s making a vacuum, I’ll bet you have an air leak between the pump and the fuel. Of course you could also use a vacuum gauge instead of your thumb.
Take it apart! I just helped a neighbour with his '62, and the old pump had a mostly broken arm inside and was barely operating. He had been plagued with fuel starvation for a couple years.
Where does the fuel pick up from the tank, top or bottom? I had one once that quit picking up from the top at 3/4 tank. Dropped the tank, pulled the sender/pickup, it was rusted off near the top. Scratched my head on that one for a while before I found it.
Put the '51 up in the air and took a peek. Fuel exits the tank towards the bottom with a steel line that comes straight out of the tank. I noticed a bit of flaky rust at the fitting. It's an original tank so probably has it's share of **** ac***ulation inside. Traced all steel fuel lines up to engine compartment. At that point, steel line has been whacked off, a newer 6" of rubber line connects that to 8" of steel line that's connected to the inlet of the pump. Closer inspection reveals two pretty severe kinks in the 8" steel line. I'm surmising, those 2 kinks along with 75 years of **** from the tank has plugged the fuel line. I'll attack it tomorrow and report back.
The fuel tanks on these old cars often have a screen or sintered bronze filter on the pickup tube inside the tank. They are really difficult, if not impossible to replace. If the car has been sitting unused for a long time, all kinds of **** will develop in the tank. Check the fuel pump with a vacuum/pressure gauge to see if it's working like it should. You can try blowing the line back to the tank to remove any junk from the line using compressed air. It may clear it out but without cleaning the tank it will return. If you blow the line be sure the gas cap is off or the line disconnected from the tank. I have fixed tanks with plugged or rusted off interior tubes, filters completely plugged, etc. The best way to cure the situation is to take the tank to a radiator repair shop and have them boil it out and check for leaks. If the interior pickup tube is not removable for inspection or repair, about the only way you can see it is with an endoscope (snake camera) and it's even very hard doing that. The easiest way is to repair the kinked gas line and buy a new tank and be done with it.
The Chinese replacement pumps are a problem. Take the pump off and operate it by hand. You should be able to hear whether it’s going to pump or not. But first, take off the “out” line and turn the engine over. Gas should squirt out the fitting. If it does, take the line off at the carb and try again.
Finally got around to checking the fuel pump. Been chasing a starter issue the last couple of weeks. Fixed that. Pulled the inlet line off the f/p, turned the motor over and there's zero suction at the pump. There's also no pressure at the outlet side either. My buddy is going tomorrow to pickup another O'Reilly's f/p. Let's see what happens!
I had a new "screw together" type fuel pump fail on me, I took it apart and discovered it has a big plastic shallow cup in there, with two umbrella type valves. The plastic warped (not apparent in this picture), and one of the umbrella type valves failed to seat. It's a shame they make some pumps so ****pily these days. Here's the body of the pump. Curiously, the larger bore fits a standard 7/8" old style check valve:
Got another f/p, still no joy. I submerged both pumps in a can of gas and manually pumped them. I got suction and pressure out of both pumps. The gas tank is completely full and the car is sitting in my driveway at an incline. With the main line disconnected from the pump, just by gravity, fuel flows through the line. I put my finger into the hole and can feel the cam lobe so my buddy spun it over by hand while I kept my finger on the lobe. I don't feel any bump in the lobe at all. It feels like it's just round. Flat lobe? The car is 75 years old with original engine. The f/p lever does bump up against the lobe leaving about a 3/16" gap that I have to close by pushing on the f/p, but I don't think that's enough. Screw it! I ordered the cheapest electric f/p I could find on Ebay. I need to get this thing outta my driveway!
^^^^^ Keep in mind a pump lobe is not like a lifter lobe. It’s an off center circle with about a 1/4” of up and down motion.
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