Nutter Bypassed Carb won't start
Sbasham1
Jeeper
- Posts
- 18
- Thanks
- 0
- Location
- Orlando, FL
- Vehicle(s)
- '85 CJ7, 258 AMC, T-176, ??, Dana ??, 32x15 mud tires
I'd love some help diagnosing a no start issue that i believe I've isolated to internal to the carburetor as the root cause. However this is my first carb, so I could be completely wrong.
I'm rebuilding an 85 CJ7 , with AMC 258 i6 / 4.2l engine (new bore, cam, pistons, and rings) and a Carter BBD carburetor (nutter bypassed and rebuilt during engine rebuild process). Where I'm at is I am trying to get the jeep running for the first time now that everything is complete (engine rebuild, carb rebuild, computer delete, and much more). This is my diagnosis process in order and hopefully you can shine some light on what i've missed or done wrong.
The jeep turns over when I turn the key. However it never starts. So if I spray starter fluid down the carb top, it sputters up and runs for a second (means spark is functioning to me).
So that means fuel isn't getting from the carb to the intake. I disconnected the fuel supply line and ran it to a bucket and confirmed fuel is being provided at pressure by the new fuel pump.
So that means fuel isn't getting from the intake of the carb to the air intake. I opened up the top of the carburetor and saw fuel sitting in the float bowl. I confirmed that the float needle is allowing more fuel in as needed, and the floats are closing the needle as it fills up.
So that means fuel is in the carb, but its not getting from the metering rods to the venturi and the air intake. I removed and cleaned the jets, metering rods, and venturi with compressed air. I reinstalled them, turned the key and still couldn't get it to run.
So as a last ditch effort I removed the stepper motor from the back, and adjusted the needles from fully into the carb to halfway into the carb. Still can't get it to run.
So after rebuilding the engine, doing the nutter bypass, and rebuilding the carb I can't get the car to start. Everything I know to diagnose seems to be functional on their own, but when I put the system together it doesn't run. What have I missed?
Thanks so much for reading this far.
I'm rebuilding an 85 CJ7 , with AMC 258 i6 / 4.2l engine (new bore, cam, pistons, and rings) and a Carter BBD carburetor (nutter bypassed and rebuilt during engine rebuild process). Where I'm at is I am trying to get the jeep running for the first time now that everything is complete (engine rebuild, carb rebuild, computer delete, and much more). This is my diagnosis process in order and hopefully you can shine some light on what i've missed or done wrong.
The jeep turns over when I turn the key. However it never starts. So if I spray starter fluid down the carb top, it sputters up and runs for a second (means spark is functioning to me).
So that means fuel isn't getting from the carb to the intake. I disconnected the fuel supply line and ran it to a bucket and confirmed fuel is being provided at pressure by the new fuel pump.
So that means fuel isn't getting from the intake of the carb to the air intake. I opened up the top of the carburetor and saw fuel sitting in the float bowl. I confirmed that the float needle is allowing more fuel in as needed, and the floats are closing the needle as it fills up.
So that means fuel is in the carb, but its not getting from the metering rods to the venturi and the air intake. I removed and cleaned the jets, metering rods, and venturi with compressed air. I reinstalled them, turned the key and still couldn't get it to run.
So as a last ditch effort I removed the stepper motor from the back, and adjusted the needles from fully into the carb to halfway into the carb. Still can't get it to run.
So after rebuilding the engine, doing the nutter bypass, and rebuilding the carb I can't get the car to start. Everything I know to diagnose seems to be functional on their own, but when I put the system together it doesn't run. What have I missed?
Thanks so much for reading this far.
