Fuel issues, engine cranks but does not start

Hi,

When this happens, do you still hear the fuel pump actuate for a second or two when you turn the key to the run position? Also, since this is a universal pump, are you certain it produces the pressure needed for the engine to run?

Do me a favor. Check to see if there are diagnostic trouble codes stored in the computer. This vehicle has an OBD1 system and doesn't require a scanner to get codes. All you will need is a short jumper wire or even a paper clip. Follow the directions in this link and let me know if any codes are found.

https://www.2carpros.com/articles/buick-cadillac-chevy-gmc-oldsmobile-pontiac-gm-1983-1995-obd1-code-definitions-and-retrieval-method

Let me know. Also, let me know how long it takes before it will restart.

Take care,

Joe

Wow, I don't like that noise. Is that coming from the original mechanical fuel pump? Also, if it is getting too much fuel, the problem is either the pump is too powerful, the needle and seat in the carburetor is worn and allowing fuel to bypass, or the float in the carburetor is faulty or in need of adjustment.

I attached a pic below and highlighted the two items I referred to. The needle and seat is lifted by the float as fuel enters the carburetor. Once the required fuel level is met based on how the float is adjusted, the needle is closed and no more fuel can enter until the float drops and the needle is lifted back off the seat, and fuel can enter.

Let me know if that helps you. Also, pay attention to that noise. See if it is coming from where the mechanical pump is located. There is a push rod between the plunger on the pump that runs to a lobe on the camshaft. I have a feeling the cam lobe is making that noise due to wear and the likely reason an electric fuel pump was used.

Take care and I'll watch for your reply. Also, let me know if you see any dark gray or black smoke from the exhaust when it gives you trouble starting. And let me know if this is a 305, 307, or 350ci engine.

Take care,

Joe

Is the new pump a mechanical pump? An electric one wouldn't be under the hood. Can you take a picture of the new pump and upload it for me to see?

Let me know.

Joe

That is really close to where the original mechanical pump is located.

I copied your picture from above. I have an arrow pointing toward the engine. On the side of the engine block is where the OEM pump would have been. See if it is there. Pic 2 shows what you are looking for.

If you look at pic 3, it is an exploded view of the pump. I highlighted the pushrod that goes runs between the pump's plunger and the camshaft. I have a feeling the lobes are worn on the camshaft. As a result, the pushrod is banging on it. This would also explain why an electric fuel pump was used. Otherwise, the camshaft would have needed to be replaced.

If it is there, remove the two bolts and remove the pump. Inside, remove that pushrod. Reinstall the pump and see if the noise is gone. Since the pump is no longer being used, that rod is doing nothing productive.

Let me know what you find.

Take care,

Joe

Hi,

Wow, if the electric pump is making that noise, it has to be bad. Is the fuel smell coming from the pump area or at the carburetor? Also, if the original mechanical pump was bypassed, there is a chance there is a problem with the camshaft.

Let me know.

Take care,

Joe

Hi,

I agree. That makes no sense. As far as the smell is concerned, if you smell it both under the hood and in the vehicle and see no leaks, it must be related to the carburetor. When the engine is running, do you ever notice dark smoke from the exhaust?

Let me know.

Joe