Oil pressure sending unit

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Oh ok I am glad you mentioned it, I wasn't aware. I was just looking at the system that works for my motor. What all should I be looking out for? I will be doing the coil as well, figured it didn't make sense to just replace one component.
Ok we're getting a bit off track here at the moment, from oil sensor to carb to timing. For now, get the carb issue sorted. Once that is done, and this is just my own thoughts, I'd get the points replaced and set up correctly. Again I'm no expert especially on points (another reason I switched to Pertronix!!) but if you can use a dwell meter, or better yet, know someone who does. set the points to factory spec for your motor. With that done, you can move on to setting the timing again to factory spec. With all that done, it ought to run like a top.
Once you've got it running smooth, then you can start to think about performance upgrades.
Again this is just what I might do in this situation.
 

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Ok we're getting a bit off track here at the moment, from oil sensor to carb to timing. For now, get the carb issue sorted. Once that is done, and this is just my own thoughts, I'd get the points replaced and set up correctly. Again I'm no expert especially on points (another reason I switched to Pertronix!!) but if you can use a dwell meter, or better yet, know someone who does. set the points to factory spec for your motor. With that done, you can move on to setting the timing again to factory spec. With all that done, it ought to run like a top.
Once you've got it running smooth, then you can start to think about performance upgrades.
Again this is just what I might do in this situation.
Oh absolutely. The petronix is way down the road, I was just thinking out loud. Once I get the carb cleaned/dialed in, we're moving on to making sure the timing is accurate. He is actually bringing a dwell meter with him so have that base covered as well.
 

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A carb kit should be pretty cheap, and a 2 barrel carb is quite easy to do. Don't be afraid to rebuild it yourself, it really is not that complicated if you take it slow and follow the rebuild instructions. I doubt that kit will be more than $30, and with some time, and carb cleaner you should be able to easily do it. One of the first carbs I did was a Carter Thermoquad from a 1972 Demon 340, I was maybe 17 years old and had no idea what the hell I was doing. Bought an auto parts kits, too it slow, cleaned all passages with carb cleaner, burnt my eyes along the way with the carb cleaner, and it came out fine, just follow the instructions to a T.
Alright this is where I’m at! Getting it all apart, definitely disgusting and dirty on the inside. I did notice that I do not have that helper spring. Small little chunk of the float is gone, but doesn’t look like there’s a hole. Regardless, ordered a new one. Don’t want a $12 part causing me to take this all apart again. Took the fuel filter off and blew through it, not blocked at all. And then….tapped it on the counter. Holy varnish or residue or something. But it came out in a small pile. There’s no way she won’t run better after just this 😂
 

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PeteG41

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I’m at a loss right now. Went to finally start her today after having the battery on the charger, and she’s just cranking. Popped the top of the carb off to make sure the float wasn’t stuck and we’re good to go there. Took the fuel filter off of the front and a little fuel trickled out but kind of a negligible amount. She ran off a 1 gallon boat tank with awful gas and a dirty carb, now I’ve got about 8 gallons in the fuel tank and everything clean. Forgive me if this is a dumb question, but is it possible it’s from a bad fuel cap? The gasket is basically nonexistent so doesn’t form a seal. Figured maybe it can’t build enough pressure? It did run it with fuel from the tank before I did the rebuild, but I’m assuming it’s because there was still fuel in the bowl. Now that everything is bone dry it’s struggling to pull from the tank?
 
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No pressure in the fuel tank, fuel gets from the tank to the carburetor by being sucked out by the fuel pump and then sent to the carburetor with around 5psi of pressure. Either the fuel line or the sock that is on the pickup tube in the tank are plugged. How did you get the fuel from the boat tank into the carburetor?
 

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Just disconnected the rubber line that was on the inlet the tank, and dropped it into the boat tank. Once I put fuel in the new tank, I just reconnected the line. It was running on fuel from the tank before I took the carb off to be rebuilt though. So that’s why I’m confused as to why it’s not pulling fuel now. Even replaced the 6” section of fuel line from the filter on the carb to the hard line, since the old one was pretty hard and had a little kink. So if anything I made it flow better, in theory.
 
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Cranking the engine doesn't create enough suction in an empty fuel line. Pour a bit of fluid down the carb and get the car started, the higher RPM's will help the fuel pump pull the air out of the line.
 
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The fuel cap is not the issue, the fuel tank has to be vented to work, although it is not supposed to be vented by that gasket, it will not hurt anything. If you have not run the car through the stock tank and fuel lines, the issue is probably that the fuel lines, or the sock inside the tank are just clogged. Happens all the time with old cars. When you looked inside the carb was there any fuel in the bowl? Easy test here, just disconnect the fuel line from the carb and put the line into a jug, then crank the engine, you should be getting a lot of fuel coming out as soon as you crank the engine. If nothing is coming out then you have either a bad fuel pump or you fuel lines or sock inside the tank are clogged. If not just connect everything back to your boat tank, and see if it now starts. Be careful when checking fuel pressure/flow at the carb with an open jug, you do not want the fuel to go everywhere, especially not on the distributor, you do not want to start a fire. If you are just not getting fuel to the fuel pump, you can remove the rubber fuel line either back at the tank, or at the front at the fuel pump and just put air pressure into it with a compressor with a blow gun and blow all the debris out of it. I would prefer to do it first from the fuel tank side, with the rubber hose disconnected from the fuel pump, so that all the debris fall to the floor and does not get pushed back into the fuel tank and the sock. Most people do it from the fuel pump side as it is easier, but unless you remove the rubber hose from the fuel sender you will just push all the junk into the fuel tank and sock. If after clearing the fuel lines, you do not get any fuel to the pump, then the sock is clogged, just remove the fuel line at the fuel pump and just blow it all out again, this time leave the fuel line connected to the sender so that it blows out the debris on the sock.
Also get some clear plastic fuel filters, if your lines are clogged with debris, you will have a ton of crap inside the lines and tank that will not just go away. You will need to watch the fuel filter and change it as soon as you see it start to clog.
 

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The fuel cap is not the issue, the fuel tank has to be vented to work, although it is not supposed to be vented by that gasket, it will not hurt anything. If you have not run the car through the stock tank and fuel lines, the issue is probably that the fuel lines, or the sock inside the tank are just clogged. Happens all the time with old cars. When you looked inside the carb was there any fuel in the bowl? Easy test here, just disconnect the fuel line from the carb and put the line into a jug, then crank the engine, you should be getting a lot of fuel coming out as soon as you crank the engine. If nothing is coming out then you have either a bad fuel pump or you fuel lines or sock inside the tank are clogged. If not just connect everything back to your boat tank, and see if it now starts. Be careful when checking fuel pressure/flow at the carb with an open jug, you do not want the fuel to go everywhere, especially not on the distributor, you do not want to start a fire. If you are just not getting fuel to the fuel pump, you can remove the rubber fuel line either back at the tank, or at the front at the fuel pump and just put air pressure into it with a compressor with a blow gun and blow all the debris out of it. I would prefer to do it first from the fuel tank side, with the rubber hose disconnected from the fuel pump, so that all the debris fall to the floor and does not get pushed back into the fuel tank and the sock. Most people do it from the fuel pump side as it is easier, but unless you remove the rubber hose from the fuel sender you will just push all the junk into the fuel tank and sock. If after clearing the fuel lines, you do not get any fuel to the pump, then the sock is clogged, just remove the fuel line at the fuel pump and just blow it all out again, this time leave the fuel line connected to the sender so that it blows out the debris on the sock.
Also get some clear plastic fuel filters, if your lines are clogged with debris, you will have a ton of crap inside the lines and tank that will not just go away. You will need to watch the fuel filter and change it as soon as you see it start to clog.
There was zero fuel getting to the bowl. The tank is actually new, the guy I bought it from was running a boat tank because if it didn’t sell, he was parking it and didn’t want to have to drain the new tank. That’s why I’m stumped. She was pulling fuel out of the tank before I took the carb off to rebuild it. There’s not much fuel so I think I’m going to put 5 gallons in from my jug, and throw some down in the bowls to prime it and see if that wakes her back up.
 

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Cranking the engine doesn't create enough suction in an empty fuel line. Pour a bit of fluid down the carb and get the car started, the higher RPM's will help the fuel pump pull the air out of the line.
Ok awesome, I am hoping it is something as simple as that. I would have tried that already, but my little 5 gallon is empty and didn’t want to put old gas into the new carb. She probably only has 8 or so gallons in the tank, so I’ll throw another 5 in and squirt some into the carb to prime it.
 
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I pour the gas right into the ventri area, dribble some, maybe an ounce or so, put the air cleaner lid back on and try to fire it up.

I might be clear in my explanation of where. In your picture you have an area to the vent hole. There are two other holes that look similar. I just basically pour the gas down the center of the triangle they make.

I've done this a few times when I let my Mustang sit too long. You might have to do it a few times to get the fuel flowing.

More adventurous people will dribble in gas while it is running. I advise against that. One good backfire and you can get hurt and the engine can catch on fire.
 

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I pour the gas right into the ventri area, dribble some, maybe an ounce or so, put the air cleaner lid back on and try to fire it up.

I might be clear in my explanation of where. In your picture you have an area to the vent hole. There are two other holes that look similar. I just basically pour the gas down the center of the triangle they make.

I've done this a few times when I let my Mustang sit too long. You might have to do it a few times to get the fuel flowing.

More adventurous people will dribble in gas while it is running. I advise against that. One good backfire and you can get hurt and the engine can catch on fire.
I ended up just popping those 4 screws off and filling up the bowl. The good news is my carb rebuild worked so I’m happy about that since I hadn’t attempted one before. Bad news is that she’s not pulling fuel. Filled the bowl up twice but once it was empty she would shut off. After work today I’m going to pull the hose from the tank to the pump off to see if I’m getting fuel there. So either have a failing fuel pump, or some blocked fuel lines. I’m guessing fuel pump
 
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I ended up just popping those 4 screws off and filling up the bowl. The good news is my carb rebuild worked so I’m happy about that since I hadn’t attempted one before. Bad news is that she’s not pulling fuel. Filled the bowl up twice but once it was empty she would shut off. After work today I’m going to pull the hose from the tank to the pump off to see if I’m getting fuel there. So either have a failing fuel pump, or some blocked fuel lines. I’m guessing fuel pump
I may be stating the obvious, but if you install a new pump, make sure the pump rocker arm is correctly engaging the eccentric cam. Don't ask me how I know!
 

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I may be stating the obvious, but if you install a new pump, make sure the pump rocker arm is correctly engaging the eccentric cam. Don't ask me how I know!
haha yessir! I replaced the fuel pump when I had my 78 F150, although that one was much easier to get to, and didn't have to do it laying on my back underneath. Before I did the rebuild and since the bowl and lines were all full, was that hiding the fact the fuel pump was going out? And now that everything is less constricted and it has to work a little harder, just doesn't have enough life left in it to do it? Could be another explanation for the crappy idle, it was getting starved of fuel. I am kind of just brainstorming out loud so please everyone feel free to give their .02.
 
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haha yessir! I replaced the fuel pump when I had my 78 F150, although that one was much easier to get to, and didn't have to do it laying on my back underneath. Before I did the rebuild and since the bowl and lines were all full, was that hiding the fact the fuel pump was going out? And now that everything is less constricted and it has to work a little harder, just doesn't have enough life left in it to do it? Could be another explanation for the crappy idle, it was getting starved of fuel. I am kind of just brainstorming out loud so please everyone feel free to give their .02.
The pump I bought from RockAuto was the Delphi MF 0007. I've had no problem with it at all in the last 4 years or so.
 

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The pump I bought from RockAuto was the Delphi MF 0007. I've had no problem with it at all in the last 4 years or so.
Thats the EXACT one I have pulled up right now from Auto Zone
. Would be nice if I just need to blow out the fuel line from the tank to the pump, but as of now I am counting on just having to replace that. Get to put my new floor jack and stands to use!
 
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Get a cheap hand activated vacuum pump and see if you can suck fuel to where the fuel line from the tank connects to the fuel pump.
1. If you get little to no fuel and the vacuum holds for a bit then you have a clog/kink/something
2. If it just keeps pumping with no vacuum being maintained then you are not picking up fuel.
3. If you pump for a bit and fuel starts to flow... you may be done!
 
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PeteG41

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Get a cheap hand activated vacuum pump and see if you can suck fuel to where it connects to the fuel pump.
1. If you get little to no fuel and the vacuum holds for a bit then you have a clog/kink/something
2. If it just keeps pumping with no vacuum being maintained then you are not picking up fuel.
3. If you pump for a bit and fuel starts to flow... you may be done!
Seems simple enough! Thank you! I thought about disconnecting the line from the tank and the pump, putting the end of the hose going to the pump into a bottle, and just try to blow through there to see what comes out. The vacuum pump is obviously more efficient though. Either way, its an experience getting to know her a little better haha technically shes a runner, albeit it poorly. But a runner none the less.
 
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