84 alternator missing plug

[jtheshowstoppper]

Well alternator has the t shape behind it but none of the wires have the t shaped plug on it. The white and white/blue end was cut off and those wires were just laying in engine bay

[Charlie69]

Check a wiring diagram.  I bought a rebuilt alternator for my 86 king cab and the new alternator came with an adapter plug to adapt to the hard body alter nator plug.

[jtheshowstoppper]

Here are some pics

[datzenmike]

 

The two white wires (above) connect to that terminal marked BATT. (picture of alternator far bottom)

 

 

 

 

 

The two cut wires (above picture) are...

 

White ..... to the top of the T and

White/Blue stripe ....to the bottom of the T shaped plug. (below picture)

 

 

 

 

You should have a Black ground wire there somewhere to the alternator case. Probably that post way over on the far left..

[jtheshowstoppper]

No black wire there

[datzenmike]

It grounds through the cast to the engine block through the mounting bolts but Nissan saw fit to also use a ground wire. You can make one from 12 gauge wire and run from case to the same bolt that the negative battery cable bolts to on the intake?

[jtheshowstoppper]

I got it charging now but my idle is high once warm its at 2000 rpm. Adjusted idle speed screw with no help.

[datzenmike]

High idle causes.

 

Choke on. This engages the fast idle cam

Fast idle cam stuck on or linkage stuck or dirty holding throttle open.

Throttle cable too tight and not letting throttle plate close fully.

Throttle shaft worn or carb hole worn and throttle place catches on sides.

Secondary stuck part open,use flashlight and look down the barrel. May be vacuum linkage stuck or jammed.

BCDD out of adjustment set too sensitive doesn't shut off. Turn adjusting screw counter clockwise to turn sensitivity down.

 

I've heard lots of people say a vacuum leak causes a high idle. I have NEVER seen this EVER. If your vehicle has the proper idle mixture set it is getting just enough fuel for the air allowed in. If you lean it out by turning the needle in, the idle slows and falters. Now what would happen if you are idling with a good idle mixture and the carb gasket had a leak??? Yes the mixture would go lean and the engine probably stall. If your idle goes up then it's either set too rich and needs more air, carb is flooding or the choke is on. In all cases you are TOO rich. Adding air through a vacuum leak and having the idle go up should tell you this.

[84720FourWheel]

Vacuum leaks may cause a high idle if it fuel injected, because o2 sensors adjust mixture. Carbs generally just run like trash with a vacuum leak.

[jtheshowstoppper]

I'll start checking those I've noticed the throttle cable isn't tight at all and the choke seems to be working it was opened up when warm

[datzenmike]

High idle causes.

 

Choke on. This engages the fast idle cam

Fast idle cam stuck on or linkage stuck or dirty holding throttle open.

Throttle cable too tight and not letting throttle plate close fully.

Throttle shaft worn or carb hole worn and throttle place catches on sides.

Secondary stuck part open,use flashlight and look down the barrel. May be vacuum linkage stuck or jammed.

BCDD out of adjustment set too sensitive doesn't shut off. Turn adjusting screw counter clockwise to turn sensitivity down.

 

 

[jtheshowstoppper]

What's weird is when I was looking at the carb while it was running it dropped to 1500 for like 20 secs then bounced back up

[jtheshowstoppper]

What's the bcdd?

[jtheshowstoppper]

When I turn the idle screw out anything lower then 1500rpm truck sounds rough

[jtheshowstoppper]

And the distributor is turned almost fully adv. Could that have been done cause of bad coil?

[datzenmike]

If one coil is not working the engine will act retarded and advancing the timing will solve but not correct the underlying problem. If you replaced the faulty part and both coils are now firing the timing will need to go back to normal.

 

Check the ignition timing. Should be 3 degrees BTDC. The distributor location doesn't matter much but where the timing is set, does.

[jtheshowstoppper]

I believe one coil is not firing I'll look for a replacement today

[datzenmike]

No........... never just replace. Prove that it isn't working and why. A new part is no guarantee that it works and the old part is better quality. What if it isn't the coil and you put a bad on on or one of poor quality.

 

 

Pull both coil wires off and place a spark plug in the end. Turn engine over with the starter. Got spark?

 

Yes....  go to Plug Wires at bottom*

No...... check for power on the + terminal of the coil with the key on.

 

Got power?

 

No.... no power on the exhaust + side coil. Replace the first fuse on the far left of the fuse box.

Yes.... briefly ground the - coil terminal and release... got spark now?

 

Yes.... there is spark....suspect the - wire to the distributor or the distributor module.

No spark.... coil is likely bad.

 

 

*Plug Wires. Check for spark on the intake and the exhaust side plugs.

 

Spark only on one side.... rotor or cap may be worn out, corroded or cracked.

[jtheshowstoppper]

So check fuses and pull a plug from each side and watch sparK?

[datzenmike]

Essentially, yes. You can start at the plugs and work back too.