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View Full Version : "Jumping" or "Pulling Power"



scrubs
03-29-2023, 07:26 PM
Please forgive the newb question, but I don't wanna fry things before I get started. Wiring is my allergy, so you'll be hearing a lot from me in the coming weeks.

About to drop motor and in regards to "sourcing a switched 12v," the BPE FAQ suggests "jumping" or "pulling "power" from the ignition coil to the distributor. It also describes "grabbing power" from the cables to the starter.

Does all of this jargon just mean running a wire with terminal ends from one + post on a device to the other device?

Thanks,

j

RBachman
03-29-2023, 08:44 PM
In this regard I believe they mean "connecting." That is, put a "jumper wire" to connect ("jump") between the ignition coil and the distributer. Take your time, read the directions for your wiring harness, ask questions here. It can be aggravating without experience, but you're not in a vacuum and have a great group of enthusiasts to help you along. The "switched 12v source" comes from the ignition "ON" position (when the key falls back to the run position when you let go of the starter.").

CraigS
03-30-2023, 07:06 AM
You have it figured out. I don't know what coil and distributer you have but FYI the old school coils often had a resister in line so they ran on maybe 10V except when the starter is cranking when they got a shot of 12V. A lot of FFRs run the battery cable right to the large lug on the starter. Some will have a solenoid mounted somewhere on the firewall so battery goes there and then another cable to the starter. You can connect to the starter but the stud is way out of the way and gets filled up fast. Some guys will use something like this mounted on the firewall similar location to the solenoid.
https://www.westmarine.com/blue-sea-systems-st-blade-compact-4-circuit-fuse-block-17054206.html
It depends on if you will need any extra power sources for accessaries beyond those available in the fusebox that came w/ the harness.

scrubs
03-30-2023, 08:16 AM
In this regard I believe they mean "connecting." That is, put a "jumper wire" to connect ("jump") between the ignition coil and the distributer. Take your time, read the directions for your wiring harness, ask questions here. It can be aggravating without experience, but you're not in a vacuum and have a great group of enthusiasts to help you along. The "switched 12v source" comes from the ignition "ON" position (when the key falls back to the run position when you let go of the starter.").

Thanks, Rbachman. I appreciate the words of wisdom and I will take your advice and ask often.

scrubs
03-30-2023, 08:18 AM
It depends on if you will need any extra power sources for accessaries beyond those available in the fusebox that came w/ the harness.

Thanks, CraigS. No extras above the full kit. Will crack the engine crate today:eek: