1973 45 hp Chrysler not charging

Hello everyone, I'm new here as I just got my first boat, and I've been reading a lot of useful information, so I'd like to start off with a thanks, as I've already found many answers here.

I do have one issue that I haven't been able to overcome yet. I have a 1973 Chrysler 45 hp, model 457hf. It's electric start, with the stator and rectifier charging system.

The motor starts, and runs fine, but it doesn't seem to be charging. I don't really know a lot about outboards, but between my brother and I, we're fairly mechanically inclined. We read about people using the radio shack rectifiers as replacements, and since it was easily accessible and only about $4, we went ahead and replaced it, but still no luck on charging.

If the rectifier is good, does that mean it's pretty much the stator without question? The motor starts and runs fine otherwise.

Also, if the charging is not working, how long can I expect the battery to last me out on the water? I have a brand new battery in it, and run the minimum of running lights as is. I ask because I'm trying to get out on the water to build a couple duck blinds this weekend if it all possible.

Thanks in advance!

Re: 1973 45 hp Chrysler not charging

I had an old electric start 55. It did not have an alternator. Battery life depended upon a number of factors: Use of lights, number of starts, And in your case hours of running.

Assuming you really do have battery, points and coil ignition:

Starting takes a good gob of power each time and in your case while running, a steady drain of power from the battery until at some point there is not enough voltage to get a reliable spark. So, because of the variables there is no answer to your question about battery life.

However, getting back to my old engine, with magneto ignition and no ignition drain on the battery, the battery would last the whole day even with starts and stops for water-skiing

Now, back to your engine. It may not necessarily be the stator. Get a VOM and check the stator while running. Disconnect the two leads and check there. It should be delivering between 14 and 16 volts AC. Check that you have the rectifier wired correctly with the stator leads to the AC terminals, red to positive and black to ground. Also, be certain the mounting screw and the back of the rectifier have good ground conductivity.

I forget the exact wiring on those older two cylinder engines However: At the engine terminal board there should be two red wires connected to the red terminal. ONE goes through the loom and eventually attaches to the battery side of the starter solenoid. This is how the battery is charged. If it passes through a circuit breaker be certain the breaker is not tripped.

Re: 1973 45 hp Chrysler not charging

I have a 1970 35 HP Chrysler (related to 35 - 55 HP) that does not have a charging system. I charge the battery every 3-5 trips (mainly day fishing). If your motor starts easy, IMO you should get 8-10 starts on 3-5 trips but experiment with your situation. Most of all, I can start manually with 1-2 pulls if needed. Down a hill and pop the clutch in 1ST Works. LOL.

Please post 2-3 pictures of your charging sys. I doubt I want one after enjoying this simplicity since 1984. 2-3 issues after fishing all night using floating lights (with a 2nd battery as usual). The rope start got us home w/o having to push start in all the stumps or walk. A 2nd battery is good Insurance and peace of mind on extended trips, if pulling is not easy. Please try pull starting before depending on it.