Idle stuck at 3000, lost anti-dieseling, low voltage

[captain720]

Basically any alternator that didn't come on your truck will need the ears "adjusted" either grind a little if it's the threaded side or just stick a big breaker bar in the non threaded ear and "adjust" it a little. The cases can safely flex some. What happens is when they get tightened the ears get squished to just barely fit whatever engine it was on before

[bottomwatcher]

On 9/21/2021 at 7:41 AM, bottomwatcher said:

https://www.maniacelectricmotors.com/alternator-rebuild-kit-for-nissan-lr180-715.html

You could try it yourself with something like this. This is not the exact kit you need. Some on here have had good luck with the new chinese. Nobody ever has good luck with parts store rebuilds. They have lifetime warranties but you have to like changing alternators or getting stranded. I try to get my originals rebuilt whenever possible. I know their history and they always bolt right back into place.

I am quoting myself because I have been through this dozens of times before. Sorry you have to fight this, if it doesn't fit take it back. 

[MaddieCycle]

17 hours ago, captain720 said:

Basically any alternator that didn't come on your truck will need the ears "adjusted" either grind a little if it's the threaded side or just stick a big breaker bar in the non threaded ear and "adjust" it a little. The cases can safely flex some. What happens is when they get tightened the ears get squished to just barely fit whatever engine it was on before

I actually think that the ears are slightly twisted, so that the bolt is not hitting the threads straight-on.  Was thinking of just drilling out the ear to make it a little more forgiving for the bolt to get in, and then cinching both sides down.  This is a beefy mount and I can't imagine drilling it out a couple of mm will weaken it.

[MaddieCycle]

Actually I couldn't even get the ears over the block mount at first. I had to use a wood block and mallet to coax it into place.  Some might be the paint, maybe I put it further out of alignment with the wood block and mallet.

[captain720]

You could also try just taking a little material with a file if it's a softer material. File is more precise than a grinder if you only need to take of a little more material.

[MaddieCycle]

Pulled it back out and saw this bushing in one of the ears was inserted a little janky, sticking out a little on both sides.  I ground down the inside face of the ear/bushing so it was smooth, 2 minutes later the whole thing was bolted in the truck no problem.  I want the 2 darn hours of my life back that I spent trying to prybar this thing in place!

[Stoffregen Motorsports]

On 9/20/2021 at 11:06 PM, MaddieCycle said:

Welp, the local rebuilder wants $250 to repair, and 2 weeks.  They want to sell me a Chinese new replacement for $189 which they stand behind. It is a reputable shop.  The question is: Do I have them try to rebuild mine, do I buy their "reliable" Chinese part for big $, or do I get a NAPA reman for $100?

I use a shop here in Auburn. They can usually rebuild an alternator for about $100 and have it ready next day. Sometimes even same day.

[Charlie69]

On 10/2/2021 at 10:36 AM, MaddieCycle said:

Pulled it back out and saw this bushing in one of the ears was inserted a little janky, sticking out a little on both sides.  I ground down the inside face of the ear/bushing so it was smooth, 2 minutes later the whole thing was bolted in the truck no problem.  I want the 2 darn hours of my life back that I spent trying to prybar this thing in place!

 

[MaddieCycle]

Strange thing has begun - voltage dips down just below 12 when using my turn signals, in rhythm with the blinking.  Does not happen with hazards, flashing beams, fan on high etc..  Assuming there is a short in the turn signal flasher module (these trucks have 2 flasher modules, one for hazards one for turns).  But I am worried that there is more to the story, including the possibility that this NAPA reman alternator is junk.

[captain720]

8 hours ago, MaddieCycle said:

Strange thing has begun - voltage dips down just below 12 when using my turn signals, in rhythm with the blinking.  Does not happen with hazards, flashing beams, fan on high etc..  Assuming there is a short in the turn signal flasher module (these trucks have 2 flasher modules, one for hazards one for turns).  But I am worried that there is more to the story, including the possibility that this NAPA reman alternator is junk.

My truck has always done this but I believe it does it with hazards too, is this a new thing for yours? All my turn signals work they just draw a lot of power

[datzenmike]

The wiring and bulbs are the same for turn or 4 ways just the switches are different.

 

 

This is a perfect example of what is wrong with the after market industry. This shit is far inferior to the stock alternator. One from a wrecking yard with 150k on it is better. What good is a lifetime warranty when it fails and leaves you stranded?????

 

 

[MaddieCycle]

People don't want to pay for things so the market demands cheap crap made in China.  Sad state of affairs.

 

It must be the turn signal flasher that sucks up power because indeed, the wiring besides that is all the same.  Strangely, it does NOT do this when my hazards are on!

[captain720]

Maybe your hazard flasher has been switched for an electronic flasher instead of a manual one? Every mechanical flasher rig I have ever driven does the voltage drop thing

[MaddieCycle]

On 10/18/2021 at 9:26 AM, captain720 said:

Maybe your hazard flasher has been switched for an electronic flasher instead of a manual one? Every mechanical flasher rig I have ever driven does the voltage drop thing

Yeah that might be it.  I'll take a look.

But bigger fish to fry is that this Napa reman is a piece of crap.  I can't get more than 13.4 volts out of it, and that's with nothing on.  Battery shows 12.5 volts with truck off so that seems fine, and it turns the starter nice and strong.  Turn on the wipers, heater, headlights, and turn signals, and the system voltage is about 12.9.  Did the usual tests for voltage between the battery and alternator and that all checks out. So it's back to Napa for me.  Stoffgren, who do you use in Auburn? I pass through there a couple times a month on my way to my land in Grass Valley.

[datzenmike]

On 10/18/2021 at 9:26 AM, captain720 said:

Maybe your hazard flasher has been switched for an electronic flasher instead of a manual one? Every mechanical flasher rig I have ever driven does the voltage drop thing

 

Mechanical or electronic flasher, it's just a switch. The load (all the flashing bulbs) has the same draw in amps.

 

 

[MaddieCycle]

Well, I would imagine if there is some kind of short in the mechanical flasher, it might cause a drain.

 

In either case, I went back to the local alternator shop, who still had my original core.  These were the people who were somewhat less than friendly to work with and wanted weeks to do the repair.  I spoke to a different person there who told me the other guy I'd spoken to was a bit of a jerk.  They are going to have mine rebuilt by next week.  I'll put that in, and then get a warranty replacement from NAPA, and then just leave that in the truck as a backup should I have any future alternator adventures.  Too bad people have become so used to cheap crap in this country. Sadly they are often the same ones who grumble that manufacturing jobs have been moved overseas. See also: the iron triangle.

Edited October 21, 2021 by MaddieCycle

[banzai510(hainz)]

I had a flaser unit draw alot of current once in my 510. all I did was reaseat flasher and it fixed it.

 

as for the bushing in the alternator ear. I would get a socket that the same size as the rim of the bushing(or OVERSIZE on the oppisite side  and put it in a vise to push it the way you want to go to give you more clreance in the alt mount. all the Datsun spcing what I seen are the same.

I notice on the O riley rebuilds 35amp alt for the 510/521 has a extended bushing also so if dont work with a 510 or 521 one needs to push the bushing to the corre3ct side to it will work. the 521 used a stamped steel mount and I neede to move it to the other side. I just used a socket and bench vise

 

 

most alternator are rebuilt Hitachi or Mitshibishi cases but thats been a long time ago and most are outsource to a far away place like Maysia or China.  I had a rock auto new alternator and it lasted 3 years of daily driving which is better but Im think 5 would be better. the standard O riley rebuilt last 8 to 13months if that on a daily 12k mile a year vehicle

Edited October 21, 2021 by banzai510(hainz)

[datzenmike]

It's two wires with power on one end and the bulbs to ground on the other. A 'short' would just keep the lights on.

 

At the instant the flasher unit connects the bulbs to the power, it appears to be a direct path to ground and the current flow spikes. The increased current flow heats the filament to incandescent temperatures and the resistance increases, limiting the  current. On a circuit with only a 35 amp alternator, specially at idle where it's barely producing anything, and with long thin wires capable of voltage drops it's no wonder the headlights dim slightly every time the signals flash.

[MaddieCycle]

Well this has turned into a real adventure.  The NAPA alternator couldn't put out more than 13.8 volts and the CHG light was coming on, so I got the local rebuilder to rebuild mine, it was really pricey.  Anyway, it is putting out 14.6 volts now.  BUT, I was driving on the highway last night and watched my voltmeter slowly fade down to 8 volts while the CHG light came on again.  Truck was still running at 8 volts.  Got off the freeway and rolled into an Autozone.  Kept the truck running, pulled off the negative battery cable (I know you are not supposed to do this) and the truck jumps up to 14+ volts.  Turned it off, battery showing 7 volts per multimeter.

 

Put in a new battery because this one has been having issues lately anyway, showing voltage difference between ground sides of the alternator and the battery. So, I have a ground issue.  I wiggled things around a bit as a temporary fix as I was on a trip, and seem to have sorted it out.  Bought a new ground cable I will install and clean that whole mess up.  Then tonight I have the dreaded repeated fuse blowing on the parking/tail/gauge lights circuit.

 

Anyway, I have to assume that when the truck was going down to 8 volts, there was something going on where the truck was not telling the alternator to charge. How does that circuit work? 

[datzenmike]

Well the rebuilt alternator is an unknown and the most recent thing changed. It IS suspect. Keep this in mind as a bad part or a soldered connection may have come undone.

 

So does the new battery fix things or not?

 

Make sure there is a good ground from the - terminal to the body sheet metal. If the ground cable is not bolted directly to the rad support, run a new 10 or 12 gauge wire from the grounded block to the fire wall.

 

What wires did you 'wiggle around'????

[MaddieCycle]

Well actually the problem existed with both the rebuilt NAPA alternator as well as the locally rebuilt one. The difference between the two is that the local one puts out 1 full volt more.  The problem was still there when I first put in the battery, so I wiggled the main battery ground cable where it connects to the tray, and tried to clean the negative post as much as I could at 9pm in an Autozone parking lot.  Once I did that, it worked, though sometimes I'd suddenly see the voltage dip, CHG light come on dimly, and the voltmeter needle jumping around. So, I am assuming there is a loose ground somewhere.  I'm going to check for voltage differences between the battery and block and various other points and see what I can find, and replace the main ground and connect it somewhere on the block.