battery charging issue has me stumped

[FishHog]

Model # of the motor ?----Is it the 3 cylinder ?--The parts for these 3 cylinder motors are quite expensive.-----Any testing done before spending the beer tokens?

They are pricey. Luckily I have a parts motor available. Yes 3 cylinder. Don’t have the number handy but can get it later if it helps.

 

[stresspoint]

? what voltage are you getting at the battery terminals when you rev the motor , should be around 14 v give or take anything less than12.5 indicates to me the rectifier is toast.
have you checked the amp output of the charge system , you can have as many volts but without amps nothing going to work.
if you are getting 14v at the battery terminals then that would indicate a cell in the battery is not catching on to whats being sent to it .
battery's will sometimes charge with a charger , start a motor just fine , but the charging system will not send enough amps to keep it up to spec .

 

[Crosbyman]

1997 Evinrude 35...I still think rightly or wrongly that we are dealing with poor connections betwen the rec/reg where voltage variations are observed as rpms go up but absent at the battery B+ post. (Assuming of course that measurement procedure is ok )

regardless of batt condition an observed voltage increase at one location should appear at the other extremity of the charging circuit since it is essentially a continous piece of wiring interconnected at the solenoid post .

disconnecting the B+ on the battery and ohming out the " link" way up to the regulator output
should measure 0 ohms

 

[racerone]

Have a bunch ( 10 or more ) of those for parts myself.-----Hopefully the oil mixing unit has been taken off your motor.-----Great motors except for the expensive electrical bits

 

[FishHog]

Seems most probable Crosbyman, but then again I've done what I thought was most probably many times now without a change.

To answer stresspoint, I get the battery voltage only and it does not change while motor is under load.

 

[FishHog]

Oil mixer was removed 20 years ago when I got it. I was duly warned of that issue. Otherwise its been great. Starting to think about an upgrade, but still runs fine, other than my no charging issue. I still get a couple days starting out of it, before I even need to worry about throwing my battery charger on it to top off the battery, but I'd like it working.

 

[Crosbyman]

how many ohms from regulator output to the disconnected B+ cable end on the battery ??

 

[saltchuckmatt]

??? meaning
View attachment 396277

He keeps calling it a regulator. See post 17.

Either it has a bad diode or the battery is "Kaput"!

 

[FishHog]

He keeps calling it a regulator. See post 17.

Either it has a bad diode or the battery is "Kaput"!

well they are commonly called regulator/rectifiers, but if it offends your semantics I'll try to do better. I suspect most knew what I was talking about.

This is the part description here on iboats.
*RECTIFIER/REGULATOR
0584890

 

[airshot]

Over my many years of owning various vehicles that use batteries, I have saw some crazy things with batteries. They can get an internal short in them that ( for lack of proper terminology) makes the battery absorb the charge and makes it disapear. Have had more than one battery appear to hold a good charge for days, but goes flat quick when you use it. Some batteries just won't accept a charge and makes you think your charger is kaput when it is really working. Batteries often do some very weird things and that has been my experience in all my years. This is the reason, everyone is highly recommending you get your battery tested !! Most places don't charge for it ( they hope to sell you another) but there are things that only show up in a good load test. I have saw new batteries with issues setting on a shelf. While it might upset the seller, I always ask for a thorough test on any new battery I buy, over my 60 years, I have had several new batteries fail, even though they showed a full 12.7 volts or more. If your battery passes the tests, then you can remove the battery from the problem list and know for "sure" your battery is good.......I am gonna bet it isn't !!!!

 

[Crosbyman]

I once had a screwy battery on my dodge Lancer years ago.. the + battery post was internally defective and drove my car's CPU nuts. the rear wiper would not shut down and the window washer pump would just run till it emptied all the washer fluid. new baatery and all was well after .!

agree... batteries are weird sometimes but I still would like a ohms reading
rectifier to B+ cable end .

 

[saltchuckmatt]

Once again Occma's Razor.

If it makes you feel any better, I had to eat crow on here myself and it didn't taste very good!

 

[FishHog]

I’m not concerned about eating crow. As soon as it stops raining here I’ll get out on the dock and verify. But I’m 95% sure it’s not the battery. I too have had weird battery issues but this one isn’t acting weird and I don’t know how it could absorb all charging voltage without a battery tester showing any voltage change on the terminals. Yet charge normally on a separate battery charger. I truly hope I’m wrong.

Appreciate everyone’s advice gives me a few things to check

 

[saltchuckmatt]

If it ain't the battery, which it's highly likely it is, it's a dirty wire. Either the grounds or power at solenoid.

Just because something shows its charging when its not hooked to a battery doesn't mean when it has a draw on it....it will test good. Battery or a wire if what your telling us is true.

Best of luck on your motor.

 

[Crosbyman]

unless we get clear answers on suggested steps to clear out this problem the desired outcome will not be reached.

 

[FishHog]

unless we get clear answers on suggested steps to clear out this problem the desired outcome will not be reached.

I’m just waiting for weather to improve and I’ll get out on the dock to do some more testing and report back. It’s brutal here the next couple days
If I get a bit of a break in the rain I’ll go pull the battery and go get it load tested today. But I have 2 trolling motor batteries that I know are good to try as well. But I’m leaning more to a bad wire or connection so need so decent weather to check those out and get some better readings

 

[FishHog]

how many ohms from regulator output to the disconnected B+ cable end on the battery ??

0 ohms.

Unfortunately not my battery. Load tested a little lower than new but still acceptable. But I tried both of my trolling motor batteries anyway just to be sure and no change. They are both 1 year old and I know I don't have 3 bad batteries. Whatever the battery voltage is at the time after starting it what I get despite revs on the engine.
Testing on the 2 leads from the rectifier goes from around 12v at idle to 23 reving up. Seemed a little high but not sure on that. Yet still 0 increase in volts at the battery terminals.
Got too cold before I traced and checked all the other wires and cleaned all connections, but will get back to that.
Starting to wonder if its possible to have increase in voltage but no amps which is why it seems to do nothing at the battery. Need to look into how to test that.

Again appreciate all the ideas and help from you guys.

 

[Crosbyman]

you have 2 yellows from the stator... they generatean AC voltage to be measured on the AC scale. across the 2 yellows.

that said the rectified voltage on the RED going to the solenoid and eventually to the battery you say gives you a voltage (DC) swing according to RPMs when measured at the rectifier. .

volts would not simply disappear along the way to the battery unless the same wire is open... be it physically broken , oxydized in thecrimp.

you stated 0 ohms rectifier to battery.... ?? yet does not reflect that reading you see at the rectifier. test point??

keeping your ground probe where it is connected .... follow your "observed" swinging voltage 12 volts from where observed on the rectifier red output and follow the wiring to the solenoid post you must see the same activity. move on towards the battery post via the big fat red wire
if you see no swing at the battery unscrew the solenoid connection clean shiny a;ll parts reconnect & retest

no offense but do not confuse infinity and 0 ohms on the meter.

beyong this I think you may need to get some shop time to help out.

 

[cyclops222]

Find the 1" X 1" fuse box on the engine side . The fuse is blown. I believe it is a 20 amp both of my Rudes have factory fuse holders.

 

[oldboat1]

Are you running a single battery hookup (starting battery)? If multiple batteries, they must have a common ground.