DarkSaga Posted November 3, 2022 Author Share Posted November 3, 2022 I don't think an electric fuel pump feeding a mechanical one is a good idea, personally. But as long as your carb is getting fuel (and not too much) I would look for other causes first. Definitely determine that the relay clicks and you have power at 87 when it does. Then check for spark. (do you have a timing light to adjust your new HEI?) A 300-6 will run with crap compression, so fuel then spark (at the right time) Yeah I don't know why the mechanic added the inline fuel pump, but it's there now so I'll leave it for the time being. [i had tested the fuel pressure prior to taking it to him and it was fine]. He also did some stuff to the carb. I'll post a few pictures so you can see if I need to disconnect or adjust anything that you know is wrong. A friend will be helping me soon and he has a timing light that we can use on the truck. Thanks for your comments Jim! Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted November 3, 2022 Share Posted November 3, 2022 Yeah I don't know why the mechanic added the inline fuel pump, but it's there now so I'll leave it for the time being. [i had tested the fuel pressure prior to taking it to him and it was fine]. He also did some stuff to the carb. I'll post a few pictures so you can see if I need to disconnect or adjust anything that you know is wrong. A friend will be helping me soon and he has a timing light that we can use on the truck. Thanks for your comments Jim! It seems like the mechanic was throwing stuff at the wall to see if anything would stick. The fuel pressure was tested as fine. He should have confirmed that (and float level) before making any changes. Does he have any experience with carburetors? I'm no expert on the YFA, but it is about the most basic carb ever built. I think you can confirm spark by yourself. Chock a wheel, set the parking brake and put the transmission in neutral. Turn the key to 'run' and go around front... unplug the relay and plug it back in. You should be able to feel it click off and then back on. If that's good you can attach your spark tester and jump the starter by touching the little blue/red trigger wire to the battery power post of the fender relay. Link to comment Share on other sites More sharing options...
Gary Lewis Posted November 3, 2022 Share Posted November 3, 2022 It seems like the mechanic was throwing stuff at the wall to see if anything would stick. The fuel pressure was tested as fine. He should have confirmed that (and float level) before making any changes. Does he have any experience with carburetors? I'm no expert on the YFA, but it is about the most basic carb ever built. I think you can confirm spark by yourself. Chock a wheel, set the parking brake and put the transmission in neutral. Turn the key to 'run' and go around front... unplug the relay and plug it back in. You should be able to feel it click off and then back on. If that's good you can attach your spark tester and jump the starter by touching the little blue/red trigger wire to the battery power post of the fender relay. I agree with Jim - especially on the idea of running an electric fuel pump into a mechanical one. Mechanical pumps have a diaphragm that has fuel on one side and the crankcase on the other. So if it fails you'll have gas in your oil. If the mechanical pump is good you may be able to unplug it and the truck will still run fine as most electric pumps will pass fuel when they are off. But don't worry about this until you get the truck running. Link to comment Share on other sites More sharing options...
DarkSaga Posted November 3, 2022 Author Share Posted November 3, 2022 It seems like the mechanic was throwing stuff at the wall to see if anything would stick. The fuel pressure was tested as fine. He should have confirmed that (and float level) before making any changes. Does he have any experience with carburetors? I'm no expert on the YFA, but it is about the most basic carb ever built. I think you can confirm spark by yourself. Chock a wheel, set the parking brake and put the transmission in neutral. Turn the key to 'run' and go around front... unplug the relay and plug it back in. You should be able to feel it click off and then back on. If that's good you can attach your spark tester and jump the starter by touching the little blue/red trigger wire to the battery power post of the fender relay. The mechanic specializes in modern diesel trucks, but said that it was a basic carburetor and that it should be a simple fix (which it wasn't). Anyway, I have a fully charged battery 12.65V and now someone here (to turn the key - but I'll make note of using your jumping the starter method for when no one is around). The engine was turned over NO SPARK with the spark tester. I checked PIN30 at the relay and it has +12V... I also checked where I connected PIN86 to the old coil White/LT Blue wire and there is +12V when the key is turned on. I need to test if PIN87 to the +positive of the HEI is getting power but having a hard time with touching the multimeter probe to the power connector at the HEI end. (It was tough to plug in so I don't want to take it out yet if I don't have to). I'm smelling fuel (carb flooding I assume), so it's definitely getting some fuel. I need to recheck the wiring. I'll try to test the relay (unplugging and plugging it back in and see if it clicks off and on). Any other tests that I can do at the relay? Link to comment Share on other sites More sharing options...
DarkSaga Posted November 3, 2022 Author Share Posted November 3, 2022 The mechanic specializes in modern diesel trucks, but said that it was a basic carburetor and that it should be a simple fix (which it wasn't). Anyway, I have a fully charged battery 12.65V and now someone here (to turn the key - but I'll make note of using your jumping the starter method for when no one is around). The engine was turned over NO SPARK with the spark tester. I checked PIN30 at the relay and it has +12V... I also checked where I connected PIN86 to the old coil White/LT Blue wire and there is +12V when the key is turned on. I need to test if PIN87 to the +positive of the HEI is getting power but having a hard time with touching the multimeter probe to the power connector at the HEI end. (It was tough to plug in so I don't want to take it out yet if I don't have to). I'm smelling fuel (carb flooding I assume), so it's definitely getting some fuel. I need to recheck the wiring. I'll try to test the relay (unplugging and plugging it back in and see if it clicks off and on). Any other tests that I can do at the relay? I tried it a few times with the key ON and each time I unplugged and plugged the relay in I did NOT hear or feel a click of any sort. The ground seems like a good one, but possibly there is a problem there (?). I crimped on a connector to the BLACK relay wire (PIN 85), sanded off the paint on the fender to bare metal, and used a self tapping screw and a steel washer to mount the ring tight against the fender wall. Should try to ground it to another spot? Either I wired something wrong (likely) or maybe there is an issue with the new Relay (not likely, but possible). Link to comment Share on other sites More sharing options...
DarkSaga Posted November 3, 2022 Author Share Posted November 3, 2022 I tried it a few times with the key ON and each time I unplugged and plugged the relay in I did NOT hear or feel a click of any sort. The ground seems like a good one, but possibly there is a problem there (?). I crimped on a connector to the BLACK relay wire (PIN 85), sanded off the paint on the fender to bare metal, and used a self tapping screw and a steel washer to mount the ring tight against the fender wall. Should try to ground it to another spot? Either I wired something wrong (likely) or maybe there is an issue with the new Relay (not likely, but possible). Sorry I did the above WRONG! I had it at ON and not RUN... Let me try again! Link to comment Share on other sites More sharing options...
DarkSaga Posted November 3, 2022 Author Share Posted November 3, 2022 Sorry I did the above WRONG! I had it at ON and not RUN... Let me try again! Just checking online about the relay mounting. Does it have to be mounted to metal for grounding? Currently I have it on the plastic covering the wheel well. I'm going to move it to the metal fender wall and see if that solves some problems. Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted November 3, 2022 Share Posted November 3, 2022 The mechanic specializes in modern diesel trucks, but said that it was a basic carburetor and that it should be a simple fix (which it wasn't). Anyway, I have a fully charged battery 12.65V and now someone here (to turn the key - but I'll make note of using your jumping the starter method for when no one is around). The engine was turned over NO SPARK with the spark tester. I checked PIN30 at the relay and it has +12V... I also checked where I connected PIN86 to the old coil White/LT Blue wire and there is +12V when the key is turned on. I need to test if PIN87 to the +positive of the HEI is getting power but having a hard time with touching the multimeter probe to the power connector at the HEI end. (It was tough to plug in so I don't want to take it out yet if I don't have to). I'm smelling fuel (carb flooding I assume), so it's definitely getting some fuel. I need to recheck the wiring. I'll try to test the relay (unplugging and plugging it back in and see if it clicks off and on). Any other tests that I can do at the relay? Are you able to back probe the relay socket at pin 87? You should see power with the key in run. (The wire between there and the distributor is all new so there shouldn't be any issue?) I'm sure you've seen a pinout for the relay. There's really nothing else to test. Fused power in = 30 Switched power out = 87 85 & 86 trigger and ground. If you have someone there have them turn the key on and off while you listen to the relay and keep a finger on it to feel it click. (no need to unplug it if someone can turn the key to switch on and off the old coil power) This may be a silly question, but can you remove the distributor cap and have your friend crank the engine to visually confirm the rotor is turning? Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted November 3, 2022 Share Posted November 3, 2022 Just checking online about the relay mounting. Does it have to be mounted to metal for grounding? Currently I have it on the plastic covering the wheel well. I'm going to move it to the metal fender wall and see if that solves some problems. You haven't posted a picture of your relay, so I can't say if it grounds through the mounting tab. If it's a plastic housing it obviously doesn't. Since I'm playing catch-up disregard my post above for the moment. .. You might try unpinning the relay socket and swapping 85 & 86. Like I said, some relays are diode protected against back feeding and reversing the trigger and ground will not switch it on. Link to comment Share on other sites More sharing options...
DarkSaga Posted November 3, 2022 Author Share Posted November 3, 2022 You haven't posted a picture of your relay, so I can't say if it grounds through the mounting tab. If it's a plastic housing it obviously doesn't. Since I'm playing catch-up disregard my post above for the moment. .. You might try unpinning the relay socket and swapping 85 & 86. Like I said, some relays are diode protected against back feeding and reversing the trigger and ground will not switch it on. Here's a picture of the relay. Product Description Nominal Coil Voltage: 12 V DC Coil Power: 1.8 W Coil Resistance: 80 Ω Must Operate Voltage: 6~8 V DC Must Release Voltage: 0.6~3.6 V DC Maximum Applied Voltage: 15.6 V DC Contact Ratings: NO 40A 14V DC Contact Resistance: 100mMAX (at6VDC 1A) Max Switching Current: 40A Max Switching Power: 560 W ***Still no click felt or heard with key to run and engine turning over. I now have it mounted to bare metal on the fender wall. Haven't tried switching PIN85 / Pin86 yet... Link to comment Share on other sites More sharing options...
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