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charging problem

Posted: Fri Jul 02, 2021 7:39 am
by noam
Dear enfield fans,

recently I won clasic 500 2017 efi, and I'm facing charging problems. the battery is lead accid 12 9AH and its new.

The charging voltage I measure is 12.3v max at high RPM, lights are on. :?:
Please advise for what could go wrong?

Regards

Noam

Re: charging problem

Posted: Fri Jul 02, 2021 12:40 pm
by Haggis
I would suspect the R/R (regulator rectifier)
It controls the charge voltage as well as converting ac to do for the electrics.
You should be getting around 14v with the engine running.
You need to go over all your electrical connectors and earth points to make sure they are OK.

Re: charging problem

Posted: Fri Jul 02, 2021 12:44 pm
by Chris [Stockport]
Just to clarify: I assume this is 14v taken from the battery terminals?
(Not the alternator or something)
Ta, Chris

Re: charging problem

Posted: Fri Jul 02, 2021 3:39 pm
by noam
thenks for replies,

first I have checked the 3 ph alternator yellow ports on idle 1-2 10.4v, 2-3 8.7v, 3-1 10.8v. on high RPM 34V, 26V AND 30V.

Is that normal? :?:

Regards

Re: charging problem

Posted: Fri Jul 02, 2021 6:03 pm
by Haggis
Check the resistance between any two yellows. It should be 0.8 to 1.5 ohms.
You will have three pairs to check. 1-2, 1-3, 2-3.
The voltage reading you get from the yellow wire , with the engine running, is A/C not D/C.
You need to put your meter on ac to measure their output.
Volts can be quite high on the ac test, as you have seen.
If that checks out ok then you should get 14v at the battery terminals, IF the R/R is working correctly.

Re: charging problem

Posted: Sat Jul 03, 2021 6:51 am
by noam
Thanks for the replies,

The voltage I have checked is AC and not DC.
The values for HIGHE RPM are: 1-2 34V (AC), 2-3 26V (AC), 3-1 30V (AC).
The values On Idle: 1-2 10.4V (AC), 2-3 8.7V (AC), 3-1 10.8V (AC).
The resistance values are: 1-2 13.9ohm, 2-3 13.7 ohm, 3-1 1.7 ohm.
Is this a sign for a alternator coils problem?

Regards

Re: charging problem

Posted: Sat Jul 03, 2021 9:25 am
by Haggis
Certainly looks wrong. All three pairs of yellow should be the same.
You have over 13 ohms on two pairs.
BUT, you appear to be getting a decent AC voltage from each one.?
Have checked the R/R yet?

Re: charging problem

Posted: Sun Jul 04, 2021 8:27 pm
by noam
Hi,

No I havn't check the R&R.
i'll do so, with my multi meter, should it be set on diod check mode?

Re: charging problem

Posted: Mon Jul 05, 2021 8:35 am
by Haggis
Diode or ohms resistance setting will be fine.
Lots of vids online on how to check a 3 phase R/R correctly.

Re: charging problem

Posted: Thu Jul 08, 2021 8:10 am
by noam
HI, finally finding the problem, the magneto coils, they are burned. replacing with new one and charging is good. Can anyone explain why relative a new bike (2017) is facing this kind of broblem?