Mercury motor question

I have a 2002 Mercury 90 horse 2 stroke. A couple weeks ago I pulled it out of the garage to check the oil before a fishing trip and when I pulled the cowling off I found a burned up mess. Apparently the voltage regulator burned up internally and caused a massive short in the wiring. The wire bundle and all the wires to the regulator were burned down to bare wire or burnt in half. Talking to a marine mechanic I guess this is a known problem with this year motor and he said he had seen motors burned up and had heard of garages being burned down due to this problem. Here is my question—-with all the wires melted down could I get a new regulator and a wiring harness and replace it myself or is this more than a simple swap? My other question is if I get it done who is a good but reasonable mechanic in the south metro or close by?

Dang Rich,that stinks.Call Dan at Bay City and ask him if you can do ityourself.

not hard to do, just get the parts and put them on. I have a repair manual and flywheel puller if you need it. Typically the main cause on this failure is not having a good connection to the battery, wing nuts only hand tight can cause this.

Quote:

---

not hard to do, just get the parts and put them on. I have a repair manual and flywheel puller if you need it. Typically the main cause on this failure is not having a good connection to the battery, wing nuts only hand tight can cause this.

---

I use nothing but Brass Nylon-Lock nuts on all my battery connections.

If you have proof of flames and soot inside the cowl, you have yourself an insurance claim.

My 125 did the same about 5 years ago and yes it is a known problem. To the public at least. Merc apparently is ok with living with the risk of a possible lawsuit because someone could die because of it.

FYI Rich, the only Service Bulletin I could find on Mercury regulators was a recall for 30-60 hp 4 strokes in 2005.

yowza
I have the same motor but a 2001 version. nothing like that so far. BK, you have the same motor?

My motor had worked flawlessly for 11 years. After the Pooh Bear tournament this year I smelled a burnt electrical smell around my motor but thought it was one of the many boats around me. I pulled the cowling off and I kind of smelled something but nothing looked burned at all. The next weekend the boy used the boat and the smell was gone and the boat worked great. He put it in the garage and plugged in the automatic charger. A week later I pulled the boat out and the damage was done. I actually pulled on one of the wires a little and it started to smoke and a small fire started again. I got a wrench and took off the positive battery terminal and the fire went out. Knowing what I know now I should have replaced the regulator when I first smelled something probably but I truly had no idea. The pictures do not do justice to the damage that is done. Almost every wire is either melted bare or burned in two.

Quote:

---

Quote:

---

not hard to do, just get the parts and put them on. I have a repair manual and flywheel puller if you need it. Typically the main cause on this failure is not having a good connection to the battery, wing nuts only hand tight can cause this.

---

This is what happen to me . DO NOT use wing nuts.

---

sorry to hear that Rich. I will be keeping a close eye out for this. I like the motor and would hate to see it burn up!

I have one more suggestion. Replace the voltage regulator with an aftermarket brand. They are cheaper an certainly couldn’t hurt.

I believe they may have fixed the shorting problem but the OEM part still fails. I’m on # 3 now. Not because I misuse or abuse it, only because I use it a lot. The most recent failure only failed to charge my battery. On the rainy river of all places.

FYI… I know that James had this same problem with the same motor as mine. This issue for merc is no secret.