advice being sought - mystery problem

[bisonfan]

Re: advice being sought - mystery problem

Update - dad tested the battery good, with motor idling volt guage is saying 12.7, 1/2 throttle 12.5, looks like we have a bad recitifier then!?!?!? I told him to test with multimeter to be sure but we would have to more then likely replace.

The switch was also giving him troubles as well, good thing it will be here tommorow.

 

[bktheking]

Re: advice being sought - mystery problem

Test the rectifier before spending the $$$:

Cut and paste from another site:


Disconnect your outboard's battery.
Disconnect the rectifier leads from the terminal block (note locations of each lead). Connect the black lead of your continuity meter to engine ground. Set your meter to ohms scale. Connect the red lead to each lead of the rectifier one at a time, note if the meter shows a short (almost zero ohms) or almost infinity ohms. Write down which leads showed short, and which showed almost infinity ohms. Now connect your meters red lead to engine ground and do the same test with the black test lead to each rectifier lead one at a time. Write down which leads showed short, which showed almost infinity ohms.
Now compare results, each rectifier lead should show either almost no resistance or almost infinite resistance with on color test lead, and then the opposite resistance reading with the other color test lead. If the reading on a particular rectifier lead doesn't change no matter if the red or black test lead is connected... it's probably shot.

 

[lmuss53]

Re: advice being sought - mystery problem

Make sure the stator is putting out current to the rectifier before you change it. Do a search here, there are lots of posts that will tell you how to check the stator. The stator makes AC current that the rectifier/regulator converts to DC and sends to the battery. If you have an hour read the post called "changed rectifier... still not charging" it's pretty involved but you will learn how this motor's charging system works.


http://forums.iboats.com/showthread.php?t=411196

 

[bktheking]

Re: advice being sought - mystery problem

Ya and that one still isn't solved, I think that one is a short in the wiring harness.

 

[bisonfan]

Re: advice being sought - mystery problem

ok results from the multimeter. Idle 12.85 volts. 1/2 throttle 13.8 volts . Dad said the volts were climbing a bit while at 1/2 throttle, is that normal? What do you think I should do now?

A Lesson learned, you can't always trust a gauge...

 

[bktheking]

Re: advice being sought - mystery problem

It's charging then, always use a meter, gauges are never accurate. I'm not sold on ignition, i'm more sold on fuel delivery but it could still be that it's not getting spark when you try to restart it. Could be many things, you need to verify you have spark when it does what it does.

 

[wilde1j]

Re: advice being sought - mystery problem

Clearly, you are getting charging.

 

[bisonfan]

Re: advice being sought - mystery problem

ok, just got off the phone again with dad, once the switch worked (had a hiccup with the ignition switch this morning), just hit the key and it was off and running. Would idle all day according to him.

So can I concluded the following?

-Battery is possibly undersized
-after sitting for 2-3 weeks that battery was low on charge and a 4 hour charge on a trickle charger wasn't enough
-the heat played a variable on the battery that is hard to measure

Do you still think it has a short in the wiring?

How come I am a bit nervous to take it out on the lake again for fear it will act up...

 

[bktheking]

Re: advice being sought - mystery problem

What kind of hiccup with the ignition switch? hmmmm

 

[mamm7215]

Re: advice being sought - mystery problem

That's a good rectifier.

 

[bisonfan]

Re: advice being sought - mystery problem

the hiccup in the switch was it sticking again. It sticks in "start" every once in a while after it has started, have to manually turn back. The new switch will be here tommorow. Installed on sunday.

 

[bktheking]

Re: advice being sought - mystery problem

Could be causing the entire issue.

 

[bisonfan]

Re: advice being sought - mystery problem

Thanks to all who have given me advice!! Unsure if the switch is the problem yet but your thoughts are helpful...

 

[Sir Robin]

Re: advice being sought - mystery problem

Took under a week for livewell timer to run down my battery. Also, my radio in the boat was in my shop on a battery and would last for weeks without charging. Do you start and stop often? Cranking is the largest power user you have unless there is a phaze liner 400 amp sound system aboard.......

 

[bisonfan]

Re: advice being sought - mystery problem

An update - The boat is at my house for the next few weeks instead of my dad's house (his boat). I replaced the ignition switch on sunday. During the replacement I found that the Magneto (big) post wire (braided wire) only had about 3-4 wires going into the connector. I replaced the connector. (Possibly not allowing full charging capacity?)

I took the boat out on tuesday night and again tonight. The volt gauge now runs at about 15 amps at 3/4 throttle. It runs great and the batttery is now holding a charge.

I am using a 2 amp trickle battery maintainer for about 12-18 hours before going out to ensure that the battery is fully charge. Today I didn't have it plugged in and it started and cranked just fine.

 

[Sir Robin]

Re: advice being sought - mystery problem

Could be causing the entire issue.

I think this was the answer
Good call bktheking

Just looking at switch and found frayed wire
Great sleuthing.........

 

[bisonfan]

Re: advice being sought - mystery problem

Alright guys starting issue is back, this time I have spent a little time doing a little research.

Knowns, switch is brand new and does operate correctly. Works great. Battery has been upgraded to the recommended size by Johnson.

The x factor is high temps and humidity. When it is hot the starter pukes out after a few cranks like a dead battery. Volt meter on battery shows 12.90 volts. Battery is good. When the temps are more reasonable, spins and starts great...

Battery line to solenoid is 12.83 and rises when charging (trickle charger).
Solenoid to starter while cranking is 11.10 volts. It won't engage the flywheel at this voltage. Just spins and spins

Can I assume a weak solenoid is to blame on the few cranks and done?

 

[bktheking]

Re: advice being sought - mystery problem

Bad wiring can cause resistance and a big voltage drop, what condition is the wiring throughout the starting system?

 

[bisonfan]

Re: advice being sought - mystery problem

Well the line that feeds the starter and solenoid are nice and plyable with no cracking in the casing. I haven't had time to check the wires tot he switch closely. I recall them being in good shape when replacing the switch, nothing that looked cracked.

I am going to try the battery to starter terminal trick to see what the results are.

 

[Chinewalker]

Re: advice being sought - mystery problem

I would bet the starter brushes need replacing. You've dealt with the battery, cables and key switch. Solenoid either works or it doesn't - not likely to go halfway. Pop the bottom cap off the starter and take a look...