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Bought a replacement alternator, but instead of plugs, you have to wire it yourself. It didn't come with a wiring diagram.
These are images comparing the two alternators, and the wires that I'm supposed to be using
PLEASE HELP!
You have the wrong ALT.
I take it the old crusty looking one is off your truck?
If so it is what we call a 2G ALT. Some call it a fire starter as the plug melts and starts a fire.
The new looking ALT is a 1G ALT.
I guess that could be a way to wire it in but you would also need a regulator for the 1G ALT as the 2G the regulator is built in IIRC.
Take the 1G back and get the right 2G ALT and just bolt it in and done.
Dave ----
Take that back and get the correct ALT. Only buy the one with the newer internal connector. and also get the new regulator connector.
Here's my current set up. I used male/female blade connectors for splice the old black/orange wire into the ALT wires, just in case I need to replace the ALT in the future.
I chose to connector the regulator connector to the exact wires as the old OEM, white wire to the green, The white on the new connector plugs into the same terminal as the OEM did, I didn't care about color matching.
Here's how the factory thought they wired the ATL on the 86' 2g ALT, Notice that two wire connector for the regulator, notice my old OEM didn't match that. Also, that small white/blk wire from the power connector, the EFI trucks don't use.
From what research I have done, in this certain situation it would still work since he is doing all the wiring. More than likely he will not do the wiring and take the alternator back.
The so called 1G has the seperate voltage regulator. The 2G has the plug-ins, on board voltage regulator and I think it also has an integral fan with the pulley? Mine, 86 on a 6.9l, has two plug-ins and the integral fan.
Also these 2G alternators have to be clocked properly to fit right. Be sure to take your old original alternator to the parts counter.
Considering the amount of wiring it will take to get this working again, I feel it would be worth mentioning that a 3G alternator swap would be worth looking into.
Do you have a junk yard close to you, the kind where you pull your own parts.
For more info, search 3G alternator swap with your engine type.
Good luck, Jim
Will return as soon as possible... if I can minimize the amount of work simply by buying the right part, I'm gonna do it. Thanks for the feedback!
Unrelated to thread-
What might cause a flexplate to have a bad spot? I bought a new starter as the other just span and didn't crank, but I just found a spot on my flexplate with no teeth, sheared.
I heard something about shims to prevent this
I don't want to replace the flexplate and then break it again, will check the forum obviously, if anyone knows where send a link
I'm going to assume you can just splice the new 2g ALT black/orange wires at the other side of your S204 OEM splice. I don't know if your truck uses the white wire out of connector C185 at the ALT. My truck doesn't.
I may have missed it, but what truck, engine and tranny do you have ?
Will return as soon as possible... if I can minimize the amount of work simply by buying the right part, I'm gonna do it. Thanks for the feedback!
Unrelated to thread-
What might cause a flexplate to have a bad spot? I bought a new starter as the other just span and didn't crank, but I just found a spot on my flexplate with no teeth, sheared.
I heard something about shims to prevent this
I don't want to replace the flexplate and then break it again, will check the forum obviously, if anyone knows where send a link
If the flywheel has missing teeth you would have to replace it. It could have been a weak starter that crashed into it either on entrance or exit. Sometimes the wrong starter is installed. You can maybe bump past the bad spot and maybe start it where you still have teeth.
If it lands on the bad spot if you have a manual trans put it is gear and move the truck a little as this will turn the motor a little and hope off the bad spot so the starter will spin the motor.
If auto trans pop the hood and if you cont have a clutch fan you can grab it and turn the motor a little to get off the bad spot on the fly wheel.
Or carry a socket that will fit the crank bolt and give it a turn.
But it will need to be changed out at some point.
Dave ----
