Evinrude 1957 35 hp 25930 charging system

[hsbjohns]

Hi,

I put a generator on my Evinrude Big Twin to keep my battery charged up. I have connected the generator, voltage regulator and ammeter as shown on the wiring diagram. When I start the motor, there is no movement of the ammeter needle, and the voltmeter shows no change either. Outside of this circuit, I tested the ammeter with a battery and load, and it showed a negative reading which I think indicated that current was flowing out of the battery to the loa. I also tried testing the generator by spinning it with an electric drill, and I did get a reading of a few volts between the generator terminals. I have a digital amp and volmeter. Can anyone tell me how to troublshoot this charging system to figure out what is not working properly?

Thanks,

Howard

 

[F_R]

Re: Evinrude 1957 35 hp 25930 charging system

Hi,

I put a generator on my Evinrude Big Twin to keep my battery charged up. I have connected the generator, voltage regulator and ammeter as shown on the wiring diagram. When I start the motor, there is no movement of the ammeter needle, and the voltmeter shows no change either. Outside of this circuit, I tested the ammeter with a battery and load, and it showed a negative reading which I think indicated that current was flowing out of the battery to the loa. I also tried testing the generator by spinning it with an electric drill, and I did get a reading of a few volts between the generator terminals. I have a digital amp and volmeter. Can anyone tell me how to troublshoot this charging system to figure out what is not working properly?

Thanks,

Howard

Before we begin, unless you are absolutely sure the vacuum cut-out switch is working properly, any generator testing should be done with the motor on a boat, and on the lake, running in gear. To do otherwise you risk dangerous runaway because you do not have a key switch to shut it down,

OK, you probably are not running it fast enough. The motor has to run at least 1800-2000 rpm to close the regulator's cut-out relay and start charging the battery. That means the generator has to be turning well over 3000 rpm, way faster than your drill goes. So get it in the water and see if it works. It should start charging at about 1/4 throttle. There may be nothing wrong with it at all.

If you find that it indeed does not work, come back and we can give you some troubleshooting procedures. No point in going through it all now without knowing if there really is a problem.

I do have to ask this though: Do you have the proper voltage regulator? Many people have tried to find a car regulator that will work..mostly without success. You do need the right kind. A few car regulators will appear to work, but will burn up the generator armature because of too high a charge rate. Has to be 10 amps maximum. The majority of car regulators won't work at all. Needs to be a type "A" field circuit. Type "B" won't work.

 

[hsbjohns]

Re: Evinrude 1957 35 hp 25930 charging system

Hi F_R,

Thanks for all the information. As always, one answer spawns more questions!

1. Is there a way to test the vacuum cut-out switch for proper operation?

2. I have a tachometer on this motor, and you are right, I have not had it much over 2,000 rpm out of the water, and I just installed the generator, so I have not tested it at higher RPM's in the water.

3. I have always wondered about this runaway issue. My manual shows 4,500max normal RPM; at what RPM does it become a runaway? Does this runaway happen very quickly, or slowly enough to do something about it? How do you stop a runaway motor, will closing the choke work as in a normal shutdown?

4. Once I get it in the water, and get the RPM's up to the range needed to operate the charging system, I should see an increase in the voltage over the normal battery voltage, and positive Amps, right?

5. The voltage regulator that I am using is marked Auto-Lite VHU-8101A 2, M and 10 Amp, 12 Volt, Negative. I bought it used on e-Bay, and was told it was working. I can take some pictures if that would help.

Thanks for all your help. I do appreciate it.

 

[dthrckt]

Re: Evinrude 1957 35 hp 25930 charging system

sorry to hijack, but where'd you get the generator? I'd like to add one to my bigtwin...

 

[F_R]

Re: Evinrude 1957 35 hp 25930 charging system

sorry to hijack, but where'd you get the generator? I'd like to add one to my bigtwin...

hsbjohns, Sorry, I haven't been keeping up with the forum. Do you have it working yet?

dth, go to www.aomci.org and place a free want and on their Webvertize pages.

 

[hsbjohns]

Re: Evinrude 1957 35 hp 25930 charging system

Hi,

Did you ever find a generator. I found mine on e-bay. They show up fairly regularly for $50 or so.

H.

 

[samo_ott]

Re: Evinrude 1957 35 hp 25930 charging system

hsbjohns, did you get the generator running? what was the issue?

 

[EN2]

Re: Evinrude 1957 35 hp 25930 charging system

Was the generator polarized, by momentarily jumping a wire on the regulator from the B terminal to the A terminal?