lahti35 Posted October 16, 2015 Report Posted October 16, 2015 Ok I've got a real stumper here. This 48 Plymouth I've got has had the original mechanical fuel pump replaced with a new one but it won't pump. I took the pump off and worked the lever and it works, you can feel it sucking and pumping. The arm that rides on the cam lobe has a shiney spot so it is making contact. When I pull the pump off and put it back on I can feel it engage the lobe. I've felt the camshaft lobe with my finger and its fine. There are no fuel line leaks or blockages I can suck fuel up the carb no problem but not blow it back through the pump. The pump itself is not leaking anywhere. I'm really at a loss here... Quote
desoto1939 Posted October 16, 2015 Report Posted October 16, 2015 Check that your metal fule line from the pump to the car is not blocked. Take the pump off and then take the glass bowel off the pump check the two small screens that are in the body of the base of the pump they might be clogged. Is the carb bowel getting filled with gas or not. Mabe the accelerator pump is stuck or need to be replaced. Can you disconnect the line to the carb and if you start the car can you get fuel to come out the line in to a small container? Rich HArtung desoto1939@aol.com Quote
Don Coatney Posted October 16, 2015 Report Posted October 16, 2015 Disconnect your fuel line at the carburetor. Remove the spark plugs and the coil wire. Spin the engine with the starter for two thirty second cycles with a one minute rest period between cycles. If fuel flows when cranking the starter stop and re-connect the fuel line. Report the results. Quote
lahti35 Posted October 16, 2015 Author Report Posted October 16, 2015 Disconnect your fuel line at the carburetor. Remove the spark plugs and the coil wire. Spin the engine with the starter for two thirty second cycles with a one minute rest period between cycles. If fuel flows when cranking the starter stop and re-connect the fuel line. Report the results. Nothing, its not even trying to pump. If I take it off the car and pump it manually it works but as soon as its on the car no dice. Fuel lines are not blocked, valves in the fuel pump are working. The sediment bowl wouldn't fill until I disconnected the fuel line at the carb and sucked some gas into it. Never had this much trouble with a mechanical pump before. Quote
Reg Evans Posted October 16, 2015 Report Posted October 16, 2015 How much fuel in the gas tank ? Quote
Jerry Roberts Posted October 16, 2015 Report Posted October 16, 2015 Try running it with a portable gas can . Quote
desoto1939 Posted October 16, 2015 Report Posted October 16, 2015 Next question You have a mechanical FP. Is there any number tag on the fuel pump. You should have a 588 fuel pump on this car. Did you get the correct pump. Ok when the pump is on the engine block and the lines are attached are you getting any fuel into the glass bowel. Do you have the gasket on the body of the pump for the glass bowel? Have you blown air back down the fuel line to hear any air bubble in the tank when the gas cap is off the car? You stated the lines are all goof what about the rubber line that connect to the metal line from the tank and this rubber line connects to the FP. Is this clear? How old is this FP is it brand new or a restored pump? Rich Hartung Desoto1939@aol.com Quote
lahti35 Posted October 17, 2015 Author Report Posted October 17, 2015 The pump is the correct airtex 73201. I notice that when I have the pump in my hand and push down on the arm it moves 1/2" before it engages and becomes tough to push, acting on the diaphragm... is this normal for these pumps? It seems to slide up and down on the pivot pin that runs through the pump body... how much slop in the mechanism is there in one of these pumps? Quote
48ply1stcar Posted October 17, 2015 Report Posted October 17, 2015 I bought a brand new fuel pump and I had to install the pump 4 or 5 times before I got the pump to work. I assume that the pump lever was not seated correctly. I found that the pump had to go on straight which is hard when the engine is in the car. Quote
soth122003 Posted October 17, 2015 Report Posted October 17, 2015 I believe there should be no slop in the fuel pump, If it moves as much as you say it does, it might be the internal spring is compressed or worn, or the pivot pin hole in the arm is wallowed out. Joe Quote
greg g Posted October 17, 2015 Report Posted October 17, 2015 Air tex are currently basically junk parts sloppily assembled in Mexico. I believe their only quality control check is whether the pump fits in the box. If to quote the USPS, If it fits, it ships. Take it back tell the store it's defective and get an other one. Quote
busycoupe Posted October 17, 2015 Report Posted October 17, 2015 Is there an air leak in the fuel line? When I first got my car it would not start without priming the carb with gas or ether. I finally figured out that there was a pinhole leak on the line coming from the tank. The leak was where the line went along the frame up over the axle and therefore did not leak when the car was parked. It was just enough to let air into the line that would prevent the pump from drawing. Check the line from the tank to the pump for air leaks. Dave B. Quote
lahti35 Posted October 17, 2015 Author Report Posted October 17, 2015 Air tex are currently basically junk parts sloppily assembled in Mexico. I believe their only quality control check is whether the pump fits in the box. If to quote the USPS, If it fits, it ships. Take it back tell the store it's defective and get an other one. Well that's interesting. I ordered one last night so we'll see if it works. I didn't install the ones that's on there now, the previous sheister (oops I mean seller) installed it. We'll see what the new one looks like! Quote
Niel Hoback Posted October 17, 2015 Report Posted October 17, 2015 I put an Airtex 73201 on two weeks ago. It looked really good, so I staked the pivot pin before I put it on and drove about 40 miles to a car show. It starts and runs very well, no leaks. A few years ago I put a big metal in-line filter between the pump and the carb. No complaints here,,,,,,,,yet. You never know. Right now I'm quite happy with it. Quote
Merle Coggins Posted October 17, 2015 Report Posted October 17, 2015 Is there an air leak in the fuel line? When I first got my car it would not start without priming the carb with gas or ether. I finally figured out that there was a pinhole leak on the line coming from the tank. The leak was where the line went along the frame up over the axle and therefore did not leak when the car was parked. It was just enough to let air into the line that would prevent the pump from drawing. Check the line from the tank to the pump for air leaks. Dave B. That's my thought too. Wouldn't take much of an air leak to keep it from drawing fuel when cranking. Not sure what was used to suck he fuel up from the carb line but if it was a stronger suction it would be able to overcome the small air leak. I'd start by inspecting or replacing the short hose hat connects the pump to the hard line. Merle Quote
JD luxury liner Posted October 18, 2015 Report Posted October 18, 2015 sorry to say my airtex 73201 never made it in the car, i rebuilt the 218 & purchased a new fuel pump when we first started the rebuild. When I was ready to test run the engine the pump failed.i could only get another pump instead of a refund. went to all electric pump with a ford inetia switch best move i made so far. 1 Quote
pflaming Posted October 18, 2015 Report Posted October 18, 2015 Did the same thing JD has done, went electric and left the pump on the block. If it likes to pump air, it can pump California smog! Since it was built in mecceco it probably doesn't know what clean air is! Quote
lahti35 Posted October 21, 2015 Author Report Posted October 21, 2015 I ordered both the airtex pump and an electric 6+/- ground pump and the electric one got here first so I installed it and it works great. Filled the carb bowl up in seconds and we were off. Quote
Reg Evans Posted October 21, 2015 Report Posted October 21, 2015 (edited) I've had one of these 6volt Carter P4259's in my 38 Dodge for several years. The coupe has always started right up so eventually all my cars will be sporting one of these. Got it on Amazon for $63.69 with free shipping. Mounted mine on the frame close to the gas tank and no pressure regulator. Edited October 21, 2015 by Reg Evans 1 Quote
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