Electrical Problem ??

Mudpuppy

Sharpest Tool
Jul 10, 2017
256
Long Island NY
First Name
John
Willys Model
  1. Wagon
Willys Year:
  1. 1951
I have a 51 wagon with the original L161...I’ve rebuilt or replaced most of the engine components including rebuilt Carter carb, ignition wires, spark coil, rebuilt the generator (it’s still 6v). Lately I’ve noticed that the headlights don’t get brighter when I accelerate the engine and today the battery barely turned her over but she did start. I took her for an hour drive averaging 45 mph (since I’ve been told the battery doesn’t charge when the engine is only idling). We stopped to have dinner and when I went to start her she was stone cold dead. I got a jump (12v I know it’s not advised) but she started up IMMEDIATELY. As we were driving home as I got up to around 35mph (with the headlights in since is was night by now) she started to sputter and hesitate. I immediately turned off the headlights but the problem persisted once I got into 3rd gear ( I have electronic OD original as well). We made it home but now I’m trying to understand what the problem might be. As I pulled into the garage with the engine still running at idle (and she was idling fine) the headlights were barely illuminating. Any thoughts ? I’m thing maybe the voltage regulator ? I took the cover off (original as well ) and there was some rust on the bottom area I guess maybe from water getting in. I sprayed it with WD40 ( was advised to do so) but I didn’t clean the contacts with fine sandpaper. While she was running a Out a volt meter to the battery leads ...reved the engine and the voltage did not increase which also makes me suspect the regulator ...thoughts ??? Help !!
 
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Did you "polarize" the generator after the rebuild?

Loosen fan belt and disconnect the wires from the generator. Run a jumper wire from field (F) (small) post of the generator to ground. Take another jumper wire and connect it to the positive (+) of the battery and touch it on the A terminal of the generator for a second. The generator if good will turn slow like a motor and it will be polarized it. Don't leave the wire from the battery to the generator for more than second at a time to prevent over heating and damage to the generator. It just takes a touch to polarize it and to see if it turns.


A generator stores a little magnetism and only needs polarized if the generator sits not used for long period of time or new rebuild.
 
After you polarize the generator and adjust the belt tension (are the pulley grooves smith and is the belt new?) check the output at the regulator. If the regulator is bad or needs adjustments (not sure if you can still adjust the output) either replace it or adjust the output so it charges the battery. You should be able to drive at night with all the lights on, have the radio, heater fan and the wipers on and still be charging the battery.
 
Walk me through checking the output of the regulator please ...the Generator was rebuilt at least 6 months ago and I had been driving it since it had been installed ...I did not do the rebuild and I assume that it was polarized by the mechanic that did the install ...I drive it every two weeks so the longest it has sat unused is maybe 3 weeks ...again can you talk me through testing the output of the regulator ...I’m a real novice and trying to learn ...I also want to eventually do tuneups
 
Do you have a voltmeter, multimeter or electronic engine analyzer?

if not, I recommend going on eBay and getting an old one that works with either 6V or 12V. I recently got a RAC brand engine analyzer that I really like. It came with an excellent book that shows and explains how to do all the tests. It does tach, dwell, volts, amps, and various generator and battery tests. I like that it uses the vehicle's battery as its power source; some of these things require their own batteries, and that can be a pain with the old analyzers.
 
Update ...took my wagon over to a friend who has more skill and knowledge ...we pulled the generator and had it checked and was working fine. Reinstalled it but had the same issue with it not charging the battery. Cleaned and tested voltage regulator ...all good. Replaced the generator armature as a precaution ...still no luck. My friend noticed the amp meter was not registering (I just figured it was a bad gauge since all I’ve ever heard was that these gauges are notoriously spotty)...anyway ...seems that the output of the generator goes through the amp meter before it goes anywhere else and since the amp meter was not functioning ...no power was being distributed from the generator. Cleaned up the amp meter connections ...son of a gun works like a charm now !! Who knew ? Anyone else have this experience ?!
 
Yup, I have had that happen back when I had Willys and old (50-58) Chevy pickups. Sorry I forgot to mention that in my earlier post. I'll bet you never forget it now.
 
All the amps from the genny go straight to the regulator, then output to the amp meter first before any other circuits slave, that’s how the system sees the higher voltage to know when to break the circuit and stop charge, an overcharge is just as bad as no or under charge


Sent from my iPhone using Tapatalk
 
wunderwillys said:
All the amps from the genny go straight to the regulator, then output to the amp meter first before any other circuits slave, that’s how the system sees the higher voltage to know when to break the circuit and stop charge, an overcharge is just as bad as no or under charge


Sent from my iPhone using Tapatalk
Click to expand...
Now what about my temp gauge ...seems to be very low ...not what I remember ...
 
64 Traveler said:
Yup, I have had that happen back when I had Willys and old (50-58) Chevy pickups. Sorry I forgot to mention that in my earlier post. I'll bet you never forget it now.
Click to expand...
No I won’t ! I’m also noticing my temp gauge is not reading like it used to ...is that looped through the amp gauge ?
 
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