Regulator Failure '95 175 Johnson

[FreeBeeTony]

Went out early this morning to go fishing.......while crossing the bay I noticed the Port Tach (twins) was behaving erratically, went to 0 back to normal and back to zero then the engine died. Right before the engine died I noticed the voltage gauge was at ~12V indicating reg not charging. For a split second I discounted the problem and was going to continue my trip assuming reg died (Low volt and no tach)....then the engine died.

I stopped and looked back at the engines and saw smoke coming out of the vents on the port engine, upon removing the hood I encountered flames! Quickly got the fire extinguisher and put out the fire. I Limped back to my slip on 1 engine.

After some investigating I found a hole burned in the top of the regulator!. The output (red) wire was un-damaged indicating the reg was not being over taxed. It seems I just had a catastrophic regulator failure. Unfortunately there appears to be some collateral damage......see pics below. .I will probably replace the stator connectors w/ bullet connectors.

I am concerned about the wires in the 1st pic that are going to a connector behimd where the requlator is installed......the insulation was burned off........I believe as a result of the flames. I plan on replacing the burned wires as needed.

My concern is when I attempt to start the engine after replacing the regulator and damaged wires.......any precautions I should take? Or should I start and hope for the best?

 

[oldboat1]

guess a first step might be to find out why a water-cooled regulator didn't cool. Maybe you've done that already.

Have to admit I would not like to tackle that repair, but with patience and time could likely be done one wire at a time.

 

[Chris1956]

Tony, If that wiring harness is as bad as it looks in the photo, you might replace it. Since the regulator is burned thru on the top, I suspect a bad short in it, versus overheat.

The ignition system and the charging system are not connected. So when the motor died, it was likely due to the fire burning a wire or component of the ignition system.

 

[Faztbullet]

All the 35 amp regulator/rectifiers when they fail on charging side blow a hole thru epoxy and catch fire..a very common problem. Things that kill em are: loose battery cables , battery selector switch nuts loose, selector switched off while running,weak impeller, maintaining battery with a charger.

 

[FreeBeeTony]

I don't think it overheated.........seems more like a defective regulator.......catastrophic failure.

Kinda glad to hear this is a common mode of failure.

Fazt, no loose connectors or anything like that.....I'm leaning towards a defective regulator!

Plan on going at it slow, clean it up and determine which wires need repair. Then replace the regulator and crank her up. Only measurement I can think of is to verify the stator wundings.

 

[FreeBeeTony]

Chris.......any suggestions on where to get a harness?

 

[Chris1956]

Fleabag has many used harnesses. CDI seems to make an aftermarket ignition harness that is available.

The concerning thing is that there is more then one harness used on that motor. There is one for PTT, one for Ign, one for charging. You would need to figure out which ones need replacing, find the OEM part number and source it from the web.

 

[Faztbullet]

Only 1 harness Chris.. 585240 but its NLA get one off Ebay

https://www.ebay.com/itm/EVINRUDE-J...528256?hash=item56c498afc0:g:edwAAOSwVq9c0HH7

 

[FreeBeeTony]

Update: replaced the regulator, repaired the wiring, replaced damaged wires going to the power pack. Hooked up the battery, primed the bulb, turned the key, alarm beeped as normal, turned the key and engine cranked...........but no fire. This was after ~4hrs work. Had to walk away.........

Pretty sure it's a no spark condition.......one thought I have is the residue from the fire extinguisher. I did hit it with a hose but not with the top cover over the optical sensor off. I know this is an optical ignition, is it possible the "optical sensor" is blocked by the residue? I haven't done any further troubleshooting thus far.

Question re stator wiring: I measured the impedance of the stator to be 0.14 ohms, the wires from the stator go to the regulator and also are in the harness going down the port side of the engine; the schematic in the manual is confusing.....doesn't really show what I just described but I used my starboard engine as an example.

I'm thinking it's something stupid......like a blocked optical sensor (wishful thinking).

I know I need to confirm the no spark condition but then what???

 

[Faztbullet]

Unplug connector on pack that has Blk/yell wires and retest. Check that yel.red from solenid to pack is correct and if no fire swap eyes. Make sure eye is shaded or hood on as bright light blinds it

 

[FreeBeeTony]

Yel/red from solenoid to pack is correct? If no fire swap eyes?

How do I access the optical sensor?

 

[oldboat1]

20A inline fuse checked or replaced?

 

[FreeBeeTony]

Where is this fuse located?
Would it still turn over if this fuse was blown?
Tach appears operational.

 

[oldboat1]

http://ww2.iboats.com/Ignition-Syste...iew_id.1542523

#23.

 

[FreeBeeTony]

Thanks!!!

Will check this afternoon after work.

 

[Faztbullet]

Fuse has noting to do with ignition...if blown motor would not do anything.. Just remove the timing wheel cover, unplug optical harness, undo spring, remove plastic retainers for optical assy and remove. Just swap the whole assy as easier and quicker than swapping just the eye.

 

[FreeBeeTony]

Can the optical sensor / timing wheel cover be cleaned?
If so, what should be used?.........Alcohol is pretty scarce these days!

 

[FreeBeeTony]

Update...........
Verified the blk/yellow were not going to gnd when key was in run position and 1 of these wires did go to gnd when key was in off position,,,,,,,,normal.
Removed timing wheel cover a found some residue from fire extinguisher under cover and on the sensor......gently rinsed w/ water and gently wiped w/ microfiber cloth.
Re-installed the timing wheel cover, hit the key and she started right up!!!!
Turned it on/off a few times and starter quit!! I probably over taxed it yesterday........probably the orig from '95.
I'm thrilled.....thanks for the insight!

Hope this may help someone later on.........it wasn't an easy job but I probably saved myself a ton of $$$$.