Jump to content
northernz

ZX alternator upgrade

Recommended Posts

Hey All, jst a question about  wiring in the zx alternator upgrade. Have installed the alternator and adaptor from Dave, the car is charging but the Amp gauge fluctuates wildly when car is running. Does this look like the correct wiring for the alternator. Car is a 12/70 240Z.

Going out to change the oil, thanks in advance for any input!

Mark

Datsun alternator.jpg

Share this post


Link to post
Share on other sites

I would spin that batt connection (A) around 180degrees, it looks dangerously close to grounding out to the center of the alt.

  • Like 1

Share this post


Link to post
Share on other sites

Did this alternator come with an internal or external voltage regulator? The conversion is for the purpose of eliminating the external regulator. So if you haven't disconnected the external regulator it may cause an erratic response inside the car on the guage.

Share this post


Link to post
Share on other sites

 This is how I've had it wired . The gauge fluctuates. I am tightening the belt as it seems too loose. Is there another way to wire this? 

Share this post


Link to post
Share on other sites

Well..... i got my son to tighten the bolt on the alternator while i pried on it to hold it in position. That seems to have done it! the gauge is behaving normally now, apparently a slipping belt will cause the gauge to fluctuate? Seems to idle better too! Going for a test drive!

  • Like 1

Share this post


Link to post
Share on other sites

Spoke to soon, test drive revealed the gauge behaving normally for a while, then fluctuating wildly again.I'm thinking that if the belt has been slipping for a while, it is worn and now slipping all the time. Does anyone  agree that a  slipping belt will cause fluctuations in the Amp gauge? Time for the MSA alt. adj arm and a new belt I think.

Share this post


Link to post
Share on other sites

Did you have any issues with the ammeter before you made the swap? I'm leaning towards a loose ground somewhere but if you didn't touch anything else all you can do is back track or shoot ZsOndabrain a quick inquiry. You should be able to sort it. Check in the trouble shooting section of the Haynes Manual also to see what would cause an erratic guage. It will probably point you right the issue.

Share this post


Link to post
Share on other sites
5 hours ago, northernz said:

Sorry, here is the correct photo! I know one wire is not secured with a nut .

20170626_151131.jpg

Not clear that you put a nut on that eyelet and tightened it.  Is that picture a representation, or your actual alternator?  Where's the picture of the adapter plugged in?

A loose belt usually just makes noise.  I would disagree that it causes erratic charging. (Edit - changing my vote to Maybe).

Edited by Zed Head

Share this post


Link to post
Share on other sites

All wires are secured properly, I snapped this pic before finishing install. ZX adapter is plugged in , impossible to install incorrectly. Gauge performed normally with old externally regulated alternator, only after new alternator was installed did gauge go wild. Immediately after tightening the belt, the gauge performed normally, but started to fluctuate intermittently during test drive, slowly but surely returning to a full time fluctuation. I will send Dave an email I guess. Thanks for the input.

Share this post


Link to post
Share on other sites
33 minutes ago, northernz said:

Immediately after tightening the belt, the gauge performed normally, but started to fluctuate intermittently during test drive, slowly but surely returning to a full time fluctuation

That's a pretty good clue except for "fluctuation".  Can't tell if it's banging off the stops or jiittering 1 mm around the center.

If it definitely got better when you tightened the belt, I'd tighten the belt again and see if it gets better again.  I just made a comment based on average behavior but if your belt is oiled up or glazed maybe it is the cause.  No matter what though, it sounds like you need a new belt.  Get rid of that weakness and you'll know if it's the problem or not.

"it is worn and now slipping all the time."

The ammeter just shows charging or discharging, and rate of each.  So, adding numbers from the gauge to the description would help a lot.  And if the battery is fully charged or partially charged.  That will affect how much the belt slips.  So, just letting the battery drain down will make the problem worse.

Edited by Zed Head

Share this post


Link to post
Share on other sites

I'm not entirely sure about what the external silver capacitor looking device on my ZX alternator is. I believe it has something to do with noise reduction. I don't see it attached to yours. Perhaps it is deleted for this application. I can post a picture of it when I get back to the car if you'd like.

 

 

Share this post


Link to post
Share on other sites

I changed my vote.  Much depends on how fast the meter reacts, and how well damped the needle is, among other things.  I overlooked the basic "changed something and it got better" description.  That's the major clue, I think.

Share this post


Link to post
Share on other sites

I agree that the belt seems to be the cause.When I say fluctuate, I mean it is going stop to stop as far as the needle can move! it is not possible to tighten the belt further , I sent Dave an email, we'll see what he says! I have to get to bed, work at 5 am! Will pick up  a new belt tomorrow, a cheap easy part to replace,

Thanks !

Share this post


Link to post
Share on other sites

Quick update. Dave replied and I have the ground wire connected to the wrong spot. He also says a slipping belt will cause the gauge to fluctuate.Will correct these tomorrow!

Share this post


Link to post
Share on other sites

I would not over tighten the belt, check the FSM for correct tension. A slipping belt may be due to a worn belt, or maybe contamination (oil) on it or the pulley. If you make it too tight you maybe stressing the water pump bearing. You don't want to do that.

Share this post


Link to post
Share on other sites

When you say that the needle is going stop to stop as far as the needle can move, are you saying that it is slamming back and forth from like +40A to -40A?

If that's the case, then I doubt the problem is simply a loose belt. I'm thinking a loose electrical connection (shunt, fusible link, battery cable, something like that), or a faulty rebuilt alternator.

Share this post


Link to post
Share on other sites
18 hours ago, northernz said:

Quick update. Dave replied and I have the ground wire connected to the wrong spot. He also says a slipping belt will cause the gauge to fluctuate.Will correct these tomorrow!

Ground wire was the way I was leaning.

Share this post


Link to post
Share on other sites

From what I see in the pictures, the ground wire doesn't appear bolted to either of the threaded holes designated for that purpose by the big "E". Picture shows attached to a smaller bolt lower and to the right of that terminal. Not positive it matters. Outside frame of alternator is definitely grounded.


Sent from my iPad using Tapatalk

Share this post


Link to post
Share on other sites

Ground wire attached at correct point now, no change, going to replace the belt this afternoon, but I'm beginning to think it's something else. It's just that after I tightened the belt the first time, the gauge performed normally for a short drive before starting to fluctuate again, and is now fluctuating in a narrower range! It is hard to tell if the belt is slipping, it is a toothed belt not a v-belt and might be making a very slight squeal at idle , but the noise does not get worse when revs are increased. Belt for 19$ is a cheap place to start.

Share this post


Link to post
Share on other sites

pop those plastic covers off the fuse links and make sure all is nice and tidy there as well.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use. We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.