1989 3.7L Merc - Electrical Burning Smell & smoke - help!

[modicon2]

Evening guys, just got off the water after being towed back to landing for the 2nd time in the last 10 trips. I'll be lucky if I'll ever get family (wife) back up on the river. I would like to fix this boat problem b/f she sells the boat. If I can't get if fixed b/f 4th of July weekend...I may be able to redeem myself.


Problem...
Pulling kids on tube and smelled something burning.
Shutdown engine and opened engine compartment and smoke came rolling out. It didn't smell like "engine hot" smell it was more like an electrical burning smell also temp gauge was reading normal.

After letting the engine cool for several minutes, I started it back and after a ~1-2minutes I noticed smoke coming from a device (that I believe is a voltage regulator...see pic). I did a google search for the part no. of device and it appears to be a voltage regulator although the wiring colors don't exactly match my shop manual's diagrams.

I was afraid to start it back up so we finally had some nice people stop and give us a tow (4miles!)...did I mention that my wife was not happy!.

What to do? what do I need to check? Is this a voltage regulator? Should I just replace it...and how difficult job?

Any help would be greatly appreciated!!!
I know that are a lot for savvy boaters with experience on this particular motor on this forum...I've just got thru reading several post & replies.

THANKS!!!

 

[Don S]

Re: 1989 3.7L Merc - Electrical Burning Smell & smoke - help!

Yes, you have the infamous 470 charging system. Magnets in the front pulley and an outboard stator with a water cooled regulator. What could possibly go wrong ???
Best thing you could do at this point is install an alternator changeover kit. The OEM part are either VERY expensive, or NLA (No Longer Available)

 

[Spare_Time]

Re: 1989 3.7L Merc - Electrical Burning Smell & smoke - help!

Yes, you have the infamous 470 charging system. Magnets in the front pulley and an outboard stator with a water cooled regulator. What could possibly go wrong ???
Best thing you could do at this point is install an alternator changeover kit. The OEM part are either VERY expensive, or NLA (No Longer Available)

like he said, your regulator is toast. I've heard of fires that started because of these poor designed regulators. Consider yourself lucky. If you are mechanically proficient, you can make your own alternator mount. All you need is a bracket to hold the alternator in line with the other v-belt pulley. Keep researching this topic and you're bound to find more advice. I can't help ya with making one because mine already came with a conversion kit done. I think the kits are like $400 but get crafty and make your own. Really not hard and then when the alternator goes, you just replace it with a regulare 1-wire alternator....easy!!!!!

Hope this Helps!

 

[modicon2]

Re: 1989 3.7L Merc - Electrical Burning Smell & smoke - help!

Thanks Guys!!!
I'll be spending the next few hours reading up on the this conversion kit.

Just tring to get a brief overview though..
This alternator kit will replace the voltage reg. and stator and what else.
Will the kit replace everything that should have got "smoked"?

Thanks again for any and all of your help!!!

 

[modicon2]

Re: 1989 3.7L Merc - Electrical Burning Smell & smoke - help!

It appears that I most likely will NOT get the conversion kit in before 4th of July. I've called a few boat motor repairs places and they all say ~$600 for part (OEM kit) and ~$250 labor and they can't even look at it until after the 4th.

Here's my question:
Can I just disconnect the 4 wires on the voltage regulator and tape them up good...and run just off my battery?
My rush is that I've committed my boat for a youth ski trip this 4th. This will be on at a private house on a lake so we'll never leave site of their dock. If it dies do to low battery, it will be an easy tow or battery replacement.

I'm not sure how/what all the voltage reg does...and how it will effect motor is disconnected. After reading it appears to be only for the charging system, so I would think that I could run all my electriconics off stand alone battery and the just the engine off the starting battery for 2-3 hours.

Thanks Again for DonS and spare_time for your comments.

 

[modicon2]

Re: 1989 3.7L Merc - Electrical Burning Smell & smoke - help!

Can anyone tell me if I can disconnect the 4 wires on the voltage regulator and tape them up good...and run just off my battery?
Will this damage anything?

Looking for a temporary 2-3 hours solution for my boat.

 

[Don S]

Re: 1989 3.7L Merc - Electrical Burning Smell & smoke - help!

I don't have a clue, I've never tried it. But what the heck. Disconnect ALL the wires from the regulator, tape off all the wires coming from the stator, start it up and run it around 1500 rpm for a while and see what happens. If the wires don't start turning red and melting you might be ok. My guess is nothing will happen, but I can't say for sure.
Personally, I would pull the pulley off, remove the stator, and reinstall the pulley.

 

[JoChek219]

Re: 1989 3.7L Merc - Electrical Burning Smell & smoke - help!

when I had a 3.7 in my old boat, I bought a conversion kit from www.breezeworks.net for about 200bucks....it worked great when I had the boat had it for about 2yrs with the conversion kit... the company was out of FL somewheres..... I would check this site first as its a great site and they help alot so why not kick them some business

 

[modicon2]

Re: 1989 3.7L Merc - Electrical Burning Smell & smoke - help!

I read several post regarding alt conv kits and breezeworks. I actually talked to them (or him) today. He is sold out of the kit and is having a hard time getting his brackets manufactored. I decided to go with some kit on Ebay for ~$289bucks that claims his kit is the best!?
I'll have to let y'all know how it goes.

I plan to leave the voltage reg in place.
Do I need to remove the black wire connecting V.R. to engine frame?

Do I have to remove the stator?
Anyone, Thanks!