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asianwills
01-17-2022, 10:33 PM
It’s probably best if I wanted to continue this conversation that I put it into a new thread that relates more to my problems.
l’ll kinda sum it up so far. First, my car one morning would crank but not start. I did all the tests and found that there was a problem with the fuel system. The fuel pump is pumping but I am getting 0 psi of fuel pressure.

I have done more tests to specifically find that the black/yellow wire from the ignition switch to the fuel cut off relay, and the blue wire from the ignition coil to the fuel cut off relay are bad. Does anybody have any experience in fixing something like this, or has anybody had any similar problems.

I don’t know if this is involved or if I just left a door open overnight, but recently a lot of my battery power is gone. I am not able to flip up the headlights and the interior lights dim when trying. The battery voltage was about 10.5, it was also very cold the night of doing all these tests.
Any help is appreciated, thanks!

https://www.3geez.com/forum/showthread.php/148550-Carbureted-Engine-Problems Original thread.

Oldblueaccord
01-17-2022, 10:45 PM
Charge your battery or replace it if it wont charge up. A fully charged automotive battery is 12.78 volts DC.

Need to keep more to one thread really so we can follow along progression.

ShiRen
01-18-2022, 05:06 AM
Yeah if you cant fully charge up your battery then that pretty obviously points to a problem with it. Also, it should be at around 14v running, if its any lower you probably need an alternator or diodes, and that would explain things if you cant charge a battery with the car

asianwills
01-26-2022, 07:11 PM
Ok so I got a new battery, and decided to also get a new fuel pump relay. The fuel pump is now getting adequate power. (12.5-12.4v) However, I did another fuel pressure test and it is still zero. The fuel pump primes and makes the whirring noise, but there is still no pressure. Is this possible even when the fuel pump turns on? Would this be a fuel pump problem, or do you think there is maybe a fuel or pressure leak in the lines?
Edit: Also, when I press down the release valve on the pressure gauge; fuel comes out. Shouldn’t there be a little bit of pressure then?

ShiRen
01-27-2022, 01:52 PM
How are you testing fuel pressure? Fuel pressure testers made for fuel injection may not even register the 5psi or so that the stock fuel pump puts out. If fuel comes out of the line off the carb then it might be good enough. Changing fuel filters and making sure there are no leaks would also be wise, but I don't really expect the pump to be bad. It is not unheard of though, I think there is some super old threads, maybe in the how-to section about changing the stock fuel pump out for a carter inline unit. Idk if that is a more reliable option or what, I wouldn't necessarily suggest it as it will be unnecessarily loud if relocated outside of the tank.

asianwills
01-27-2022, 05:00 PM
How are you testing fuel pressure? Fuel pressure testers made for fuel injection may not even register the 5psi or so that the stock fuel pump puts out. If fuel comes out of the line off the carb then it might be good enough. Changing fuel filters and making sure there are no leaks would also be wise, but I don't really expect the pump to be bad. It is not unheard of though, I think there is some super old threads, maybe in the how-to section about changing the stock fuel pump out for a carter inline unit. Idk if that is a more reliable option or what, I wouldn't necessarily suggest it as it will be unnecessarily loud if relocated outside of the tank.

Ya I am just using a normal fuel pressure gauge, but my manual says that the fuel pressure should be 17 psi. I already bought a new pump for the tank, so i’ll just put it in and see what happens ig.

Edit: I should be more specific. I am measuring the pressure where the fuel line meets the fuel filter under the hood.

asianwills
01-29-2022, 05:10 PM
I’m so sorry, this is so embarrassing. You’re right, I was reading the manual wrong. It says 17 kPa, which transfers to 2.6-3.2 psi. If only I didn’t read it wrong then I would have way sooner known that my fuel system is fine, with 2.8 psi. This is a stupid mistake considering all the time I spent on the fuel system, and spending $90 on a new fuel pump. Sorry guys.

Either way the car still won’t start. I’ve been trying to look at the timing belt, thinking maybe it’s out of time. But I can’t find the TDC pointer on the crankcase. I’ve been looking forever.

I did a spark test with a spark tester, one of the ones with the bulb that lights up. There would be a big/brighter spark, kinda the initial spark. But then it would kinda have smaller sparks leading up to that next bigger spark. Is this fine?

I doubt it would be compression right, cause it was running perfectly fine the day before. There isn’t much to air either, shouldn’t be hard for the engine to get air right?

I’m kinda just lost honestly. To recap the problem. I went to go start it on a cold morning, it idled low because it was cold. That’s when the auto choke turns on though, I left to let the engine warm up. Then when I came back the engine was off and it wouldn’t start again.

Edit: I just put in new spark plug wires and now it is not doing those small flashes in between. Still won’t start. Also is the floater/fish bowl thing or whatever supposed to drain over time? Because mine does, it looks like there might be a tiny bit of dried liquid around the the seams of it. But it could just be dirty.

Oldblueaccord
01-30-2022, 03:53 PM
I would look at the belt itself and see if a few teeth are missing on it since the spark seems erratic. The top timing belt cover comes right off.

With the rotor, under the distributor cap point at spark plug wire #1 you should be able to find the TDC mark pretty easy. Also the cam sprocket should say UP on it if its aligned correctly.

ShiRen
01-31-2022, 09:07 AM
The tdc mark is on the flywheel.

Oldblueaccord
01-31-2022, 05:58 PM
The tdc mark is on the flywheel.

he wrote he cant find it on the flywheel at this time.

Dr_Snooz
01-31-2022, 07:22 PM
I’m so sorry, this is so embarrassing. You’re right, I was reading the manual wrong. It says 17 kPa, which transfers to 2.6-3.2 psi. If only I didn’t read it wrong then I would have way sooner known that my fuel system is fine, with 2.8 psi. This is a stupid mistake considering all the time I spent on the fuel system, and spending $90 on a new fuel pump. Sorry guys.

It's happened to us all. And at this age, it's not a bad idea to swap in a new pump as a maintenance item.

If you remove the cover on the cam gear, like OldBlue describes you can turn the crank and see very quickly if your timing belt has failed. If the cam gear doesn't turn with the crankshaft, then you have a failed timing belt.

Float bowls going dry kinda points to problems with the carb. The gas is either not getting to the carb, or is not staying there properly once it gets there. If you're sure it's filling when you turn on the key, but then disappearing after you turn it off, then it's only going 2 places. Either it's leaking to the outside of the carb, in which you'd smell it, or it's going down into the intake and flooding the engine. You can clear flooding by holding the gas pedal to the floor and cranking for about 10 seconds or so. Incidentally, a flooded engine will also smell like gas, but only while you're cranking.

There is also a possibility that your float has failed. That will bring you to a screeching halt and it's difficult to know it's happened, except that you notice the bowl is empty and the car won't start.

Usually, you can rule out fuel system issues with a can of starting fluid. Crank the engine and shoot starting fluid in the carb throat. If it starts, you have a fueling issue. Be careful with starting fluid. It is a very effective oil dispersant, and too much will make your engine bearings go dry. Not good. Just use it briefly for testing, and stop if you hear clattering.

asianwills
01-31-2022, 07:55 PM
If you remove the cover on the cam gear, like OldBlue describes you can turn the crank and see very quickly if your timing belt has failed. If the cam gear doesn't turn with the crankshaft, then you have a failed timing belt.

Float bowls going dry kinda points to problems with the carb. The gas is either not getting to the carb, or is not staying there properly once it gets there. If you're sure it's filling when you turn on the key, but then disappearing after you turn it off, then it's only going 2 places. Either it's leaking to the outside of the carb, in which you'd smell it, or it's going down into the intake and flooding the engine. You can clear flooding by holding the gas pedal to the floor and cranking for about 10 seconds or so. Incidentally, a flooded engine will also smell like gas, but only while you're cranking.

Usually, you can rule out fuel system issues with a can of starting fluid. Crank the engine and shoot starting fluid in the carb throat. If it starts, you have a fueling issue. Be careful with starting fluid. It is a very effective oil dispersant, and too much will make your engine bearings go dry. Not good. Just use it briefly for testing, and stop if you hear clattering.

This is very helpful, thank you very much. Especially the part about the 2 possible places fuel could leak to. I knew it might be possible to leak into the engine, but I didn’t stop to think that all that fuel might be stopping a start. Especially considering how long ago it has started and how many times I have pumped fuel in the carburetor for it just to leak. I will definitely look at these things, thanks.

asianwills
02-03-2022, 05:20 PM
Ok, so I checked timing again with this new information and it doesn’t look like there was a problem with timing.
Since maybe the float bowl is draining into the engine, I cleared the flood. I then tried to start start it with some carburetor cleaner down the throat. It took a lot of cranking but it eventually started and died out.
I slowly waited for the carburetor cleaner to dry and then tried a few more times. The more times I did it, the better it got. After a few tries I eventually got it to run on its own. However it did not run very well, quite a bit of smoke from the back and a high idle.
Now that I know with that, I am thinking that it is likely still some kind of fuel problem. Like I said, I did a fuel pressure test in the front and it was good.
Because of that I am thinking the carburetor needs some good cleaning and a rebuild kit. Tell me if I’m wrong, but I’ve already bought one. Thanks to the carburetor rebuild threads I think I’m pretty set up though, I hope.
Thanks for your guys’ help on this thread!