1979 45hp Chrysler Electrical issue.

[sikm8]

Hi Guys,

I have been fixing up this old donk and thought I was all done when I noticed the battery was draining fairly quickly, so I checked tbe voltages at the rectifier, I got 11.5v on the DC (I think this was more the battery reading) but the real issue is the AC, only 6v :grumpy: running at high idle ~1000rpm.

What would cause this? Where should I start?

I think its a battery ignition system. Model: 459H9H

Thanks.

 

[MickLovin]

Re: 1979 45hp Chrysler Electrical issue.


Could be either your stator,which by the sounds of 6v it possibly is, but I am also unsure what reading you should get when you put an ohm meter on it. and 11.5 volts is more than likely your battery voltage as it should be charging at 1000rpm and therefore have a higher voltage from the rectifier/regulator
Have you had it running?

 

[sikm8]

Re: 1979 45hp Chrysler Electrical issue.

View attachment 229552
Could be either your stator,which by the sounds of 6v it possibly is, but I am also unsure what reading you should get when you put an ohm meter on it. and 11.5 volts is more than likely your battery voltage as it should be charging at 1000rpm and therefore have a higher voltage from the rectifier/regulator
Have you had it running?

G'Day Mick,

Thanks for the quick reply. Is it possible to verify the type of elec system by the pics below. the image you posted has a 3 wire stator, mine has 2.

The other thing is, i'm not sure of the correct testing technique for the AC side. I just placed a multimeter and measured AC voltage directly off the 2 AC point on the rectifier. I tested the stator resistance (2 red wires removed from the rectifier) and it gave me 0.3 Ohm.

While I have the flywheel off, I will clean and re-gap the points, I believe the gap should be 0.2", is this correct?

The motor run nicely, starts first time, idles and rev well (haven't taken it too high yet, no prop and running off ears)

Thanks Mate.

 

[Frank Acampora]

Re: 1979 45hp Chrysler Electrical issue.

Can you get your hands on another flywheel for testing? Weak flywheel magnets will cause a low alternator output. Try testing with a screwdriver. It should ne difficult to pull off the magnets--but that is purely subjective--I don't know a way to actually test magnet strength.

 

[sikm8]

Re: 1979 45hp Chrysler Electrical issue.

Can you get your hands on another flywheel for testing? Weak flywheel magnets will cause a low alternator output. Try testing with a screwdriver. It should ne difficult to pull off the magnets--but that is purely subjective--I don't know a way to actually test magnet strength.

Thanks Franks,

I did test that. The screw drive wasn't too difficult to get off the magnets, sounds like it could be the problem (I know excessive heat can weaken magnets). Does the stator resistance reading sound right?

Can you tell from the pic, what type on elec system I have?

Thanks Mate.