72' 510 Wagon Charge Light Stays on.

[wagoon]

Recently did an L20B swap and in need of driving her. I noticed that the Charge Light will not go out. When I do the turn signal it has a faint blink to it. So far I have changed the Alternator with a new one and it is good because I checked it before I left the shop, changed out the voltage regulator, the ground is connected to the bolt on the voltage regulator, all connections to the alternator are clean, so what is going on with the Charge light not turning off? I'm not sure what the heck is going on. Any advice would be helpful.

[datzenmike]

Throwing parts at it isn't the answer. It's gets expensive and very likely the new alternator is a piece of shit made in China. I hope you kept your old one because if it didn't fix the problem... it's probably still good.

 

This just started when you changed the engine?

 

Changing the engine won't cause this so did you keep and use the alternator that was on the L20B? or did you keep the 510 alternator???? If the L20B alternator .. what year vehicle was the L20B out of????

 

Is the battery ground cable bolted to the head just behind the fuel pump?

 

Do you have a ground strap from the block to the body sheet metal, or from the negative terminal to the body sheet metal?

 

Are the battery terminals clean and tight?

[wagoon]

So I ended up with the same Alt from Mitsubishi. The battery ground cable is connected to the starter. Should that be connected to the bolt on the block or the carrier bolt at the head?

 

The ground strap is from the negative terminal to the bolt on the voltage regulator.

 

Battery terminals are new and are tight.

 

I think the L20b came from a 78' 620.  

[banzai510(hainz)]

So I ended up with the same Alt from Mitsubishi. The battery ground cable is connected to the starter. Should that be connected to the bolt on the block or the carrier bolt at the head?

 

Both are good grounds.

 

 

try using the old volt reg.

 

Is the T connector on alt connected.

 

 

78 might be a transistion year for a Internal volt reg alternator.. X ref rock auto on here for the part numbers

[wagoon]

My Alternator has the 4 prong connector. I'll connect the ground to the block later and see how it works. So what exactly is going on, is it a bad ground connection?

[datzenmike]

So I ended up with the same Alt from Mitsubishi. The battery ground cable is connected to the starter. Should that be connected to the bolt on the block or the carrier bolt at the head?

 

 

I think the L20b came from a 78' 620.  

 

 

My Alternator has the 4 prong connector. I'll connect the ground to the block later and see how it works. So what exactly is going on, is it a bad ground connection?

 

 

OK the Nissan alternators were Hitachi not Mitsubishi so I don't know about them. The 510 and the 620 should have Hitachi alternators.

 

The Hitachi has a two wire plastic plug, a ground and a hot lead from the output. I suppose that's 4 wires but they are not on a 4 prong connector.

 

If you are using a '78 L20B alternator then it IS and internally regulated unit and won't work on your 510 until you do a simple conversion to get rid of your external regulator.

 

 

A picture of this alternator would help.

[banzai510(hainz)]

the Mitshibishi unit will have a 4 pin to a 2 pin pigtail adapter when it comes with the unit.also early 521s might have this 4 prong also as I have seen.

 

I have seen these before but should still work.

If not find a Hitachi alt that plugs striaght in to your standard harness

[q-tip]

If it is charging properly then you have the two wires from the car backwards. Switch them and verify that it is still charging.

[banzai510(hainz)]

then you have the two wires from the car backwards

 

what 2 wires?

 

 

The Key is the alternator a IR type from a 78 620 as stated. If yes then the volt external volt reg needs to get pulled and a jumper made. to make the light go out. then you might have auto choke Battery draining issues.

 

still to many I dont knows on this(vauge) swapping a motor doesnt mean you need to swap the alternator if there was a L20 in there already or even a L18 with the bigger alt mounts.

If L16 and still stock alt. then best we know about this uses the samller 35amp set up. As 30 years of another owner it its hard to just guess I did a L20 swapp and we know all the specifics of the other moter and was the diat alternaot water pump ect is swapped

[datzenmike]

All stock 510 use an external voltage regulator for their alternators. You can run any engine, L18, L20B and can still use the stock alternator.

 

IF you replace the engine with one made after '78 it will have an internal regulated type alternator and will conflict with the external regulator already on the car. There was probably nothing wrong with the one you replaced when the charge light stayed on. The regulator too is probably fine it's just that the two don't go together.

 

The fix is easy and all you need do is join two wires after disconnectiing the external regulator. This is an expensive lesson.

[wagoon]

Damn, you guys are so full of Datsun knowledge....It was the wires that were backwards on the T-connector. I noticed only 2 wires...haha...and flipped them around...thanks!

[banzai510(hainz)]

Dam I was WRONG!!!!!!!!

[q-tip]

Damn, you guys are so full of Datsun knowledge....It was the wires that were backwards on the T-connector. I noticed only 2 wires...haha...and flipped them around...thanks!

That's what I did