Did a motor swap a few weeks back, put a motor in a 98 Ford ranger out of a 97 ranger 4.0l. it runs for a matter of seconds then dies. There is a green and red wire coming off of alternator not sure where it goes to. Also it starts with key on run position. Anyone encounter similar issues? Any help would greatly be appreciated 👍

 

Welcome to the forum

No, nothing similar

1998 and 1997 4.0l Rangers used different fuel systems, so you need to use the upper and lower intake, and fuel injectors from the 1997 on the 1998 engine

In cab fuse box pull out fuse #24
Now turn on the key and see if STARTER motor comes on
If not then could be ignition switch or "radio" wiring issue

If starter still comes on then you have the wrong wire connected to the "S" wire post or "Starter post", on starter relay
Starter relay(solenoid) is on inner fender, it has 2 large posts and one small post
Red/blue stripe wire should be on small post, "S" post
One larger post will have Battery Positive wire and 1 to 3 other wires with it
The Other larger post just has ONE wire, and only ONE wire


Alternators have 3 wires and a short white jumper wire

There is a Stud and Nut terminal on the back of alternator, its called B+ terminal, it has a larger wire attached, can be black/orange, red, or ?? wire, but it will be a larger wire with an eyelet

Also on alternator is a 3 wire connector, has yellow, green and white wire
White/black wire is just a short jumper that plugs into another location on alternator
Yellow/white wire goes to engine fuse box, fuse #6
Light Green/red wire runs into the cab, for Battery Light on dash