Another Podtronics thread

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Sorry if this has been covered before but I’m hitting a bit of a brick wall here.

I’ve been having problems with the charging system on my 1974 850 MKIIA so I’ve purchased a Podtronics reg/rec and I’ve fitted it using a mounting plate supplied by AN so all is good on that side of things.

Where I’m struggling is that I’ve removed the zener diode, the capacitor and the rectifier, connected the 2 yellow wires from the reg/rec to the alternator leads that led to the rectifier and connected the red and black leads to the battery as per the instructions that came from Podtronics. Now I’ve done that I have no power to any electrical components. I’ve checked the obvious and the fuse on the negative lead to the battery is ok so all I can think of is should I be doing something with the positive and negative leads that went to the capacitor and the rectifier, if that’s the case then what do I do with them?
 
wired correctly to the battery terminals as per positive or neg earth?
Does the bike have single or three phase alternator and is the podtronic unit correct for this
All connection clean & tight
 
Drama over. I decided to change the fuse carrier and all of a sudden I’ve got power.

All I need to do now is start the bike and see if it’s charging :D
 
IIRC the entire bike runs through the 2 brown/blue wires on the cap being connected...red does not matter

That's how I recall it.
Did you tie the blue/Brown wires together at the Cap?
 
Drama over. I decided to change the fuse carrier and all of a sudden I’ve got power.

All I need to do now is start the bike and see if it’s charging :D
If you have the original fuse holder sometimes the contracts can sink with age and not make contact with the fuse
 
Well it’s running well enough but unfortunately the alternator light stays on and I’m getting no voltage gain across the battery when I blip the throttle. I know there’s a school of thought that suggests digital meters can give odd readings but I no longer have an analogue meter and I don’t have an ammeter fitted. I’ll probably go old school on it and see if the headlight gets visibly brighter when the engine is running but the front of the headlight isn’t fitted at the moment because I’ve been messing about with digital instruments.

The only other place I can think of checking is to see what the voltage is across the wires coming direct from the alternator then check again where I’ve got the connections to the reg/rec in case there’s an issue between them though it’s a new wiring harness so I’d rate it unlikely to be an issue but it needs checking.
 
Well it’s running well enough but unfortunately the alternator light stays on and I’m getting no voltage gain across the battery when I blip the throttle. I know there’s a school of thought that suggests digital meters can give odd readings but I no longer have an analogue meter and I don’t have an ammeter fitted. I’ll probably go old school on it and see if the headlight gets visibly brighter when the engine is running but the front of the headlight isn’t fitted at the moment because I’ve been messing about with digital instruments.

The only other place I can think of checking is to see what the voltage is across the wires coming direct from the alternator then check again where I’ve got the connections to the reg/rec in case there’s an issue between them though it’s a new wiring harness so I’d rate it unlikely to be an issue but it needs checking.

IIRC there are 2 quick connect terminals connected to the negative side of the capacitor and they need to be jumpered together if you remove the cap.
 
I had the same problem and recall that power is routed from the battery through the capacitor to the keyed switch. If you cut out the capacitor there is no power to the switch.
 
The 2 negative leads to the capacitor have been linked from the start so that’s not the problem.

I’ve got power and the short term issue was a defective fuse carrier which was unfortunate because it was a new item bought at a show but I had a spare that was purchased for a different bike so that solved the problem.

I don’t think the new connections from the Podtronics unit will be the issue because I always apply a light coating of grease then crimp a ferrule on the cable before fitting whichever connector I need so they stay secure and corrosion free.

Probably the best way to see if it’s charging will be to just ignore it for a while but have the headlight on whenever I’m doing any work that involves me running the engine and if the battery doesn’t lose its charge there isn’t a problem.
 
@Andy_B with the engine off, you should see 12.6 volts assuming your battery is charged.
At engine idle, this will probably go down a little - around 12 volts.
Bringing your engine up to between two and three thousand RPM you should see just under 13 volts.

Checking these three stages will allow us to rule out cabling and things like that.


When you fit a combined regulator/rectifier, it is essential that you disconnect the original zener.
The original zener dumps to ground at 12.75 volts, where as you'll find an aftermarket regulator/rectifier has a higher setpoint.



Another Podtronics thread
 
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Ok, here’s the next question for today.

I’ve got two wires going from the alternator to the Podtronics which is also linked to and putting charge into the battery at the correct voltage. I changed the wiring this morning so that I’m feeding from the Podtronics into the battery via the original negative (live) and positive (ground) terminals used by the standard rectifier because it keeps things a bit neater and I’m planning on ordering a 4 pin block connector to tidy it up even further. Is that a bad idea?

I’m going to pop into the workshop and put my meter across the positive and negative feeds from the Podtronics with the engine running and see if that’s reading any different to the reading I get across the battery and that should clarify things a bit.
 
I think it's fine to connect your podtronics to the original rectifier wires, as you know it worked using these wires previously.

It also makes sure that you have not interrupted the NU (Brown/Blue) that goes off to feed the bike via the ignition switch!

Always put your meter across the batter +ve and -ve terminals.
It will help iron out some of the wild fluctuation you see.
 
Ok, here’s the next question for today.

I’ve got two wires going from the alternator to the Podtronics which is also linked to and putting charge into the battery at the correct voltage. I changed the wiring this morning so that I’m feeding from the Podtronics into the battery via the original negative (live) and positive (ground) terminals used by the standard rectifier because it keeps things a bit neater and I’m planning on ordering a 4 pin block connector to tidy it up even further. Is that a bad idea?

That's exactly what I've done.

I’m going to pop into the workshop and put my meter across the positive and negative feeds from the Podtronics with the engine running and see if that’s reading any different to the reading I get across the battery and that should clarify things a bit.

If your meter has a 10 amp range, put it inline with the battery (the fuse holder is convenient for that). With ignition on you'll see current flow from the battery. With engine running the current should change direction and show charging. Having 2 meters, amps and volts, is the ideal test setup.
 
Well it’s now putting a charge into the battery. I’ve no doubt it would have been fine with the original charging system in place but in my nativity I just assumed that a new wiring harness would be good and parts of the build done prior to me buying the bike were correct.

I’d previously checked the output of the alternator and found it was good, separated the terminals connecting the alternator to the harness, greased them and replaced them, so far so good. What I hadn’t done was check that ac current was getting to the rectifier and today found that it wasn’t. I checked for continuity along the wires between the alternator connections and the rectifier connections and it was ok so scratched my head, had a brew and went back to the workshop.

At this point I cut the plastic cover from the harness where it connects to the alternator and there was the problem. There were 2 bullet terminals held by a pressed steel connector which then took the alternator wires making the connection but unfortunately the end result was that all 4 wires were effectively joined together :mad:

I’ve now put a hard joint between wiring harness and alternator so that the wires are separated and everything works as it should. I’ve got heat shrink covers over each side and now it’s been tested I’ll wrap them together with self amalgamating tape to keep any damp out then order a block connector to take the Podtronics unit to the original rectifier terminals and that’s it, job done :)

thanks for your help, I tend to use this forum as a reference book because most issues are covered somewhere hence me very rarely posting.
 
So the new harness was made in such a way that output from the alternator was being shorted to ground?

Glen
 
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