Truck will not start after installing batter cables incorrectly

Hi Weston,

All engines need three things to start and run. Spark, fuel, and combustion. Since you eliminated two of the three, I would agree that it appears to be a spark issue. If you hooked the battery up backwards it is possible that you sent voltage through the coil in the wrong direction and hurt the coil. The way this works is your distributor needs high voltage to deliver spark to the plugs. The distributor interrupts the primary circuit in the coil which creates your voltage spike for the secondary circuit in the coil to deliver it to the distributor and then the plugs.

I suspect that when you hooked the battery up backwards that you hurt the distributor or secondary circuit in the coil. It sounds like when you say it acts like it wants to start, I sounds like you have a weak spark. If so, this would most likely be the coil.

What I would do, is pull one of your plugs out and hold it against the engine block with the wire hooked up and see if you have spark. If not, go backwards in the system and find out where you have voltage. If you have voltage going into the coil but none coming out then that is your issue. If you have it coming out of the coil but not at the plug then your distributor or wires are the issue.

Let me know what you find and we can go from there.

Okay. That is progress. I suspect you have two issues. The knocking noise coming from the distributor is most likely something to do with the distributor itself and not caused by something else. I have seen a lot of distributors make a knock or clicking noise and it was the rotor hitting the cap. Start it up and put your hand on the cap and see if you can actually feel it.

I would then remove the cap since you just replaced it and see if there are any marks on the inside of it. If not, it could be an issue with the gear or shaft.

Next issue of stalling in reverse, I think you are correct that the carburetor is probably not adjusted.

However, start with the knocking noise and once that is fixed, run through setting the timing and then adjust the idle speed and mixture. Again, the smoking if gray or dark smoke is most likely too much fuel.

It is important to set timing first, then adjust the carburetor because timing will effect your carburetor setting.

Let me know what you find. Thanks

Okay. I bet your rotor or cap broke because it was hitting it. If this happens again, it may not be incorrect installation. I had a distributor that was worn out and the shaft was not rotating true and it kept breaking the rotor because it was hitting the cap.

Here is a video that gets pretty deep in setting the timing on Chevrolet engine. I attached the specs on where to set your timing. Keep in mind you just want to set base (idle/initial) timing and the vacuum adjust will handle total timing. I circled in red where your vacuum advance line is, just make sure you unhook that before you start.

I attached your timing specs but don't go solely on these. The engine will begin to run really smooth when it is in a good position. So if the spec is 8 degrees BTDC and your engine runs better at 12, go with 12.

https://youtu.be/UYGU7mTwsZc

Let me know if you have questions. Lastly, if you are not comfortable doing this, then I would not try it on your own. The first time you set this, it can be very confusing.