Help with HDJ81 alternator diagnosis (1 Viewer)

[finderscuba]

I installed 2 brand new batteries in November. Lately I've noticed that my voltage gauge is often below the middle. Occasionally I've had to manually charge my batteries in order to be able to start the truck. I'm suspecting my alternator is going but I'm unsure how to diagnose it.

Yesterday I measured 11.72 volts at each battery with engine off.
Then I measured 12.52 volts on the LH battery and 12.72 volts on the RH battery while running. Revving up a bit would only make a small difference.
When I turned on the headlights, rear defroster, heated seats, fog lights and rear heater, the voltage dropped to about 11.7 volts.
This morning I had to get a boost to get it started - on the charger now.

So at first I thought the alternator had good output, but when loaded up, it doesn't seem to be coping. This is when the temperatures are relatively mild (-10°C). I'd like to take it in somewhere to do a battery and alternator test, but I'm hesitant because of the uncommon 12/24V switchover. Can a regular alternator test be done?

My searching found reference to a 1991 Tercel alternator as a direct replacement for the HDJ81. Can anyone confirm this? The other route would be to have my alternator rebuilt, but will the parts be readily available? Just take it to a reputable alternator shop?

I'd appreciate any advice/wisdom as I'm getting sick of hooking up the battery charger every few days!!

 

[finderscuba]

Just to add...
the belts seem tight, and all connections seem sound. I do not get any warning lights on the dash, and no abnormal noises from the alternator.

 

[Radd Cruisers]

Sounds like your alt.

Best to have your old one rebuilt.

Yes, there are other units that fit. I think you're right about the Tercel alt, but i haven't compared the numbers lately (have used them before).

Note that the Tercel alt has lower output.


~John

 

[9180ltd]

Another side note, you should see between 13.5 to 14.5 volts while running with a good alt. Even with load. If less your over loaded or have battery issues.

 

[83bj60]

The way he describes it I would say the brushes are worn out or the retaining springs have overheated and don't give proper tension and the collector is caked with gunk. Cheap to fix, but as located under the AC compressor, it looks like a bear to take out and reinstall.

 

[bigbrowndog]

I would also check the brushes they could be worn too short. I understand this alternator is also on the HDJ100, HDJ105,PZJ70,Spacia 98to01SR40. 3S-FE I have heard the Lexus 450 has the same alternator. Might pay to cross reference the alternator with the 3 liter Lexus also as I think it maybe the same but with 160 /180 amps[different pulley]. Goodluck.

 

[finderscuba]

Thanks for all the advice. I'm pulling the alternator tomorrow and taking it to an auto electric place to be rebuilt. Twice yesterday, the charge light, and the fuel filter/timing belt lights came on while driving, then went off. I'm thinking it's just a matter of time before the alternator craps out completely.

I'm sure hoping this won't be too difficult to get out.

 

[83bj60]

Good luck, and do let us know how you took it out. You do have AC on your truck, right?

I just noticed you're in Winnipeg, you can always call Simon if you have trouble, he's right in your neck of the woods...

 

[Squash]

Most good shops can load test your alt., takes less than 5min.
You seem to have it nailed down already.

Another solution is to remove your negative post/posts, if the engine stops your alt is shot, at this time you may also want to turn on all lights, wipers, fans, just to make sure your altenator is putting out enough juice.

Sometimes the three pronged rear altenator wiring harness is bad which leads to flickering dash light syndrome because of poor ground.
You can unplug and re-install or do the redneck pinching of female terminals before you plug in again.
This has greatly reduced flickering light syndrome for me...mind you if I wasn't so cheap I'd purchase a new harness.

 

[finderscuba]

Most good shops can load test your alt., takes less than 5min.
You seem to have it nailed down already.

Another solution is to remove your negative post/posts, if the engine stops your alt is shot, at this time you may also want to turn on all lights, wipers, fans, just to make sure your altenator is putting out enough juice.

Sometimes the three pronged rear altenator wiring harness is bad which leads to flickering dash light syndrome because of poor ground.
You can unplug and re-install or do the redneck pinching of female terminals before you plug in again.
This has greatly reduced flickering light syndrome for me...mind you if I wasn't so cheap I'd purchase a new harness.

I've already dealt with the flickering dash lights due to the loose alternator connector. Definitely not the issue here. However, my charge, water fuel filter and timing belt lights are coming on steady more and more often. Also confirming a bad alternator. The lights turn off when I rev up the engine.

You should never disconnect the battery on any car while running. It's called "load dump" and it can fry any electronics on board and your alternator. I design electronics for construction and agricultural equipment and we have to test for this all the time.

Alternator is still in place. Life got in the way this week. I hope to pull it this weekend. Shouldn't be too bad of a job since the weather is just below freezing (t-shirt weather for us). And yes I have AC. I haven't really studied it, but it doesn't look that bad. Took 2 hours to remove the alternator on my wife's Golf. But it was buried in there. The LC looks like I could possibly get it from underneath. Yay - time to get dripped on by road salt and grime!! Think I'll give it a quick spray down first.

 

[finderscuba]

I pulled the alternator last night. It was pretty easy. Disconnected both batteries, disconnected alternator. Loosened the top two bolts (one for adjusting) from above. The bottom one can be reached from underneath - have to remove front skid/splash plate first. Removed bolts then twisted and turned the alternator to fish it out from below. Then loosen the AC belt tensioner to remove all the belts.

The auto electric place I took it to said the stator was toast just from looking at it when I dropped it off. They'll be calling later once they get it opened up. On a side note, this particular shop rebuilds alternators for the Toyota LC mine trucks. So I should be in good hands. Also offer a 2 year warranty. Beacon Auto Electric - Winnipeg.

 

[Squash]

Nice to see you've resolved the issue with a knowing shop at that. Did you get an upgraded unit?
Bet they'll do starters as well and even conversions if asked, mind you it sure is nice to have 24v starters in winter.

 

[83bj60]

I pulled the alternator last night. It was pretty easy. Disconnected both batteries, disconnected alternator. Loosened the top two bolts (one for adjusting) from above. The bottom one can be reached from underneath - have to remove front skid/splash plate first. Removed bolts then twisted and turned the alternator to fish it out from below. Then loosen the AC belt tensioner to remove all the belts.

The auto electric place I took it to said the stator was toast just from looking at it when I dropped it off. They'll be calling later once they get it opened up. On a side note, this particular shop rebuilds alternators for the Toyota LC mine trucks. So I should be in good hands. Also offer a 2 year warranty. Beacon Auto Electric - Winnipeg.

Great info! What made the guys believe the stator was fried? Did you notice a smell of burnt resin? You now it could be simply carbon/copper grime covering the coils... Wish you the best!

 

[finderscuba]

Great info! What made the guys believe the stator was fried? Did you notice a smell of burnt resin? You now it could be simply carbon/copper grime covering the coils... Wish you the best!

I think he just noticed some burnt or worn insulation on the windings.

At this point, the shop still has my alternator and has spent the entire week looking for replacement parts. I'm losing faith in them. They mentioned that pretty much the entire insides need to be replaced. Also the housing as there was some play in the bottom mount (??) I'm hoping they can just weld or sleeve the bottom mount. It was solid on the truck.

Anyway, I'm still waiting for an estimate (4 days later). I'm hoping this won't break the bank. I did send them the part numbers from Toyodiy but they said they didn't help.

I need my truck back on the road!!

 

[Cancruiser]

Could you buy one from OZ and have it shipped to you??
My guess, by the time it is over with them trying to source parts and add their profit then their labour, it may be cheaper/convenient to buy a refurb or new unit from overseas.. Check on the OZ forum for advice

 

[UpsideDown]

Best to go for the Tercel Alternator if this is going to get you down.

Get a lifetime warranty unit from Napa. I don't have the part number here at home, but I do have it somewhere at work.

~JOhn

 

[Squash]

Something wrong here...did you say they repaired mine trucks as in HZJ 7*s
Our 1HD-t's and the HZ's share many parts and identical parts.

Phone other shops or get to a wreckers if needed.

 

[simonliew]

is this the one across from J-max.
l got them to rebuild an alternator once and it took a long time and yadyyada,,,,,,,,,,,
so now l send all my rebuild to Ace auto electric.
Simon\
TLC

 

[BC40]

I just had the same symptoms on my bj60. Hadn't noticed the charge light wasn't coming on when I went to start. Realized no charge with the voltmeter low.

Anyways, mine turned out to be just the brushes, easy fix.

Good luck on yours.

 

[Radd Cruisers]

Try this one:

Napa Canada numbers here....

Application: 1992 Tercel

part number: 138587 Alternator 70 Amp

Comes with a 4 groove pulley, so that will have to be changed.




HTH,

~John