Voltage question......

Dave81 · Post by **Dave81** » Sun May 04, 14 8:34 pm

Had the car out in the sun today just to put it through a heat cycle. Had a slight issue which i sorted, but during the issue it led me to testing the battery. Are these readings around normal?

Ign off = 12v
Engine at idle = circa 13v
Engine at idle + headlights on = 12.7v
Engine around 2000-3000RPM at a guess = 16v upto 17v
dropped back down to idle and the voltage dropped back down to around 13v as before.

Not concerned.....just curious?

Mossy68 · Post by **Mossy68** » Sun May 04, 14 8:50 pm

We're all these readings taken from battery Dave ?

I may well be wrong. But I'm sure the 16 to 17 v @ 3000 rpm seems high ?
The voltage regulator should stop the alternator sending this much to the battery. I would only expect to see this sort of voltage when full field testing.

Sorry in advance if I'm wrong mate. ( I usually am !!)

GJUK · Post by **GJUK** » Sun May 04, 14 10:46 pm

Watches with interest (due to my recent charging issues)

Dave-R · Post by **Dave-R** » Mon May 05, 14 11:46 am

Voltage regulator is not working. You should have a max of around 14.5 volts no matter how high the engine rpm.
Check the regulator is grounded well to the chassis. It needs to be. If it is it is kerfuffled.

Your alternator is not putting out enough at idle either. So either your idle speed is too low, the wiring crap and offering some resistance, or it's just a crap alternator. On standard mopar wiring all the alternator output goes through one usually badly corroded terminal on the bulkhead connector and then to the amp gauge in the dash.

Try running a wire directly from the alternator to the battery +ve terminal and see if you get better voltage at idle. If you do consider the "mad electrical" upgrade to by-pass your amp gauge.

Dave81 · Post by **Dave81** » Mon May 05, 14 8:38 pm

Thanks chaps...thought the power reading was high.

Gary......Yes. All taken from the battery terminals.

Dave.......Bulkhead bypass is already in and have the +'ve connection to the Alternator. This was done prior to my ownership!

Can someone point me in the direction of what i should be seeing at idle and under load??

Dave-R · Post by **Dave-R** » Mon May 05, 14 9:06 pm

Automatic car should be at 800rpm in gear.

Ideally you want 14.5 volts at all times when the engine is running.

So check the regulator is grounded well. If it is you need a new one and if you are lucky the new one will work. They don't always.

Dave-R · Post by **Dave-R** » Mon May 05, 14 9:08 pm

Fitting relays for the headlights will stop the voltage dropping when you put the headlights on too.

GJUK · Post by **GJUK** » Mon May 05, 14 9:21 pm

(I have a brand new voltage regulator if you are in need of one)

Dave81 · Post by **Dave81** » Mon May 05, 14 11:06 pm

Cheers for the offer Jon, but i may aswell get one and do the MAD conversion.

Out of interest Dave. As the Alternator is directly linked to the + battery terminal using cable only, how will the voltage regulator, regulate the feed?

Steve · Post by **Steve** » Mon May 05, 14 11:27 pm

The MAD conversion is slightly more complicated than just running a wire from the alternator to the battery Dave. I did a step by step guide when I did it on the Polara. Easy enough as I managed it. It cuts out several potentially bad connections as Dave said, ie, the in throught bulkhead con, the ammeter, back out the bulkhead con etc etc.....well worth doing

cadboy · Post by **cadboy** » Tue May 06, 14 6:59 am

Dave if you are going to do any changes to the wiring, then as Steve said do it the correct way and it is a little more than just a wire from alternator to the battery.

You need to run cable from battery to inside to replace the original wiring.

cadboy · Post by **cadboy** » Tue May 06, 14 7:04 am

Dave81 wrote:
Out of interest Dave. As the Alternator is directly linked to the + battery terminal using cable only, how will the voltage regulator, regulate the feed?

Regulator is wired to the field wiring of the alternator and that is how the voltage is regulated as the filed is switched.

If you need help Dave I am happy to drop in and help as I have done my car and it is better.

Steve · Post by **Steve** » Tue May 06, 14 8:22 am

http://www.moparuk.com/forums/viewtopic ... ead+bypass

Dave81 · Post by **Dave81** » Tue May 06, 14 8:30 pm

First gents, thanks for sticking with me on this!!!

I' a complete novice when it comes to any form of electrical work over and above re-wiring a plug!!

So i have many simple/stupid questions to follow.......

Steve,

......Thanks for digging out that post of yours, top stuff mate!!!
Q: Is everything that you ebay linked what you needed for the conversion or were the extras required on top?

Q: Where did you get the Voltage regulator from?

Ali, thanks mate will keep you in mind when i inevitably ruin a runnin (albeit wrong) car!

Went out tonight and think my own simple mistake on Sunday has lead me to the conclusion of a few unrelated reasons my car is the way it is.

First (original to me) battery i had on the car was bulging and leaking ever so slightly. This was replaced earlier this year for a new halfrauds one. Fault now known to be overcharging.

The Elec Ignition has leaked dielectric grease or some such all down the inner fender.........I'm now guessing that this is also related to to much power running through and liquifing the grease??

On searching tonight i also found this.....

Filko VR383HD Voltage regulator. Searching shows its a Chinese box with voltage set point of 14.3v..........

So the upgrade as already been done.........

Not sure why they went straight to battery from the alternator and not to the starter relay as per the MAD upgrade?

Only additional parts i got with the car when i bought it was this.......

Never connected the dots to what it was until tonight, but its numbers show the same info as the filko above....14.3v set point.

Q: The Filko as fitted has a green 2 pin connector. The C545 has red.......is this of any significance?

Pulled the Filko off and this is the internal view.....

Q: Is there anyway to test these off the car?

Big Q: What would you do...........
Trust that the previous (Yank) owner did the conversion properly and fit the chrome regulator and see what it says?

Pull the lot and rewire as if it had never been done?

Interesting to see that even though when driving in the past its been overcharging, it did not fry anything.......Just slightly cook the ecu and battery!

Dave-R · Post by **Dave-R** » Tue May 06, 14 8:38 pm

Well judging by the amount of corrosion and dirt I can see in your photos there is a chance the voltage regulator was not grounded to the bodywork very well. So that may be your issue. Like I said in my first post, make sure the body of the voltage regulator has a good connection to ground (and the -ve terminal of the battery) otherwise it will not work.