Generator Johnson 1960 40 HP

[lifes great]

Does anyone know a simple way of testing this generator? None of my books have the resistance readings. I opened it up and cleaned up the brushes and tested the windings, all appear ok. When it’s hooked up and the engine is running (idle) and I touch the (F) field to the hot side of battery with an amp meter it looks like it’s about 4 amps. However I’m not sure if it’s a discharge or charge of 4 amps. With the engine off it will show it also. I also bought a new regulator (vr203) and when I run it through it I get nothing at all. I tried all different (rpms) but nothing. Question is it possible that the battery is fully charged (new) that it won’t allow the regulator to kick in? All connections were good and a good ground. Thanks.

 

[rolmops]

Re: Generator Johnson 1960 40 HP

Good morning.<br />These generators will start producing juice when your engine runs at about 2000 rpm at less than that you will get no reading on your amp meter.The top amperage they produce is 10 amps.<br />You have to polarize your generator before you use it the first time.Do this by connecting the positive lead to the battery and then using a a small jumper wire to make a MOMENTARY connection between the bat and arm on your regulator.<br />Then when you run the engine at 2000 rpm you should have good amperage.In order to bank test them you need a growler.<br />When I first got mine I simply reversed directions and made it run off the the battery on the work bench. It came up to great rpm which made me decide that what goes one way will also go the other way.I do not know if this is scientificaaly true but the generator works great. <br />The volume 1 Seloc(1956-1970 2 cylinder up to 40 horse) has a large section on testing and servicing these generators.<br />Good luck.

 

[lifes great]

Re: Generator Johnson 1960 40 HP

Hello and thanks much! <br />The regulator I bought is new but for a 1960 falcon they say it works well for this generator. It’s the old mechanical type. It says to jump the (f) to the hot side of the battery to polarize it? I will try it the way you said. When you hook it to a battery by itself on the bench the generator will run? What do I hook to what, the field to ground or arm to ground or field to arm? Then just reverse the polarity? Thanks again my friend. <br /><br />PS: I have a background in electronics, so fire away. Thanks

 

[rolmops]

Re: Generator Johnson 1960 40 HP

Hello again.<br />I had it laying on the bench and if I remember correctly I connected to ground and field,although it has been 5 years.I do know for sure that ground was involved.Just do it with some thin wires and clips and while being careful the generator does not take off in flight,just touch it for a real short time to make a connection.Come to think of it,I treated it as if hooking up a starter.<br />be careful.

 

[lifes great]

Re: Generator Johnson 1960 40 HP

Thanks again.<br />Manny

 

[rwise]

Re: Generator Johnson 1960 40 HP

Been a long time , but I think its bat to field. You can test a generator by removeing the armature lead and without the drive belt (or whatever) then apply power to the armature, it will motorize. I would not do this for long time.

 

[lifes great]

Re: Generator Johnson 1960 40 HP

Yep! Just did that; Removed the belt and hooked the ARM to the hot side, bingo it ran. However the field side didn’t do a thing but look silly. I then ran it again the ARM in line with an amp meter just to see how many amps it pulled for it to rotate, 20 amps 30 to start then down to 20. Now all I have to see is if it will produce as a generator. Keep in mind that I didn’t have the regulator in line as I did these tests. I’m still not sure if it’s the field or the arm that puts out the charging amps.

 

[rwise]

Re: Generator Johnson 1960 40 HP

Like I said before, tis been a long time. I think its going to be the armature that ptoduces the curent. all you have to do is turn it faster than it ran!

 

[lifes great]

Re: Generator Johnson 1960 40 HP

Thanks

 

[boots101]

Re: Generator Johnson 1960 40 HP

Does anyone know where I can find an old vintage 12 volt generator that might work on a '66 40hp Johnson? I've got all the parts and wiring, but need the generator, pulley & belt. it would need to fit the factory bracket....

 

[HighTrim]

Re: Generator Johnson 1960 40 HP

Post a wanted ad at aomci.org or try the salvage yards listed in the FAQS

 

[F_R]

Re: Generator Johnson 1960 40 HP

I read all the way through this long thread and was about to write up the correct way to check out that generator, only to realize is is an over 8 year old thread that you have re-opened. But to answer your question, those gererators are around. Try e-bay and motor salvege yards.