1995 Mercury 200 Ignition Problems

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Update on my little project. I went to the Lake Norris meetup and had an awesome time but had a little hiccup. We went out for an awesome run for about 45 minutes or so to go get some lunch. Boat was running really well. I still had my porpoise but I was able to tab through it okay. On the way back down river / lake I felt something a little weird like a pop or thump or surge and then I noticed port motor was not running correctly. I ran it like that for 5 - 10 minutes as I was trying to figure out what wasn't working right. When we made it to the rafting up spot, I shut that motor off and it didn't want to restart. I had to limp home on one (two miles to the marina).

When I got back home, I brought it to my mechanic folks at Maryland Offshore. They diagnosed it as faulty ignition components. They said that their policy when it comes to faulty ignition components is to replace everything. In this case their definition of everything is the stator, trigger, voltage regulators and switchboxes. The cost of this was going to be $2,600 or plus the diagnostic fee of $288. I’m already grossly over budget on the boat and Mrs. Bill Payer is not the happiest of campers with regards to how much we’ve spent so far so I decided that I really need to learn this stuff and I brought the boat home.

I need to give a big shout out to Bruce (Demag67) as he’s been a huge help in answering a bunch of my stupid questions and just helping me feel confident that this stuff isn’t that hard.

Maryland Offshore wanted to replace the stator, trigger, voltage regulators and switchboxes and after talking Bruce and telling him that my tachs have not been working correctly on either motor he recommended that I buy some voltage regulators for the good motor as well. I sent an order off to Boats.net on Friday for all of it so I will be well armed for this upcoming weekend.

It dawned on me Friday evening that I have my old 2.4s in the garage and they share the same switchboxes. I decided that I would start educating myself on Saturday and try replacing one of the switchboxes. Just to throw it out there, I didn’t grow up working on cars. After I got out of the Navy, I bought a Fox body mustang and the speed bug bit me. With that nasty virus, I learned my way around the 302 for about 12 years or so and that is the extent of my mechanical prowess. On the electrical side of things, I was essentially an Electronics Technician (actually an FT for anyone that cares) in the Navy that gave me plenty of schooling on electrical / electronic theories but the real world experience was troubleshooting out of flowcharts and replacing circuit cards and power supplies. Okay TMI I’m sure.

I have purchased a Factory Service Manual but it is scheduled to arrive this week. On Saturday I pop the cover off and started looking for things. I don’t know my way around these motors so it’s taking me a long time to figure stuff out. It probably took me 30 minutes to realize the switchboxes are stacked one on the other, lol. I bought a spark tester and I find that the port side has spark and the starboard side does not. I wasn’t sure which switchbox was port or starboard so I did a continuity check from the coils and determined that (thanks Bruce). I pulled the starboard switchbox off and replaced it with one off my 2.4s of unknown condition. I had the same result of no spark on the starboard side. I decided to take a look at the Voltage regulators. Thank goodness for all the pictures on the internet because I had no idea what to look for. I finally find them hiding behind the coil plate. The connections have some electrical tape on them. I pulled the tape and I see that there are melted connections starting at the regulator side. It looks like I have found my culprits.

I am posting this to help me think through some things, give an update of the boat, ask a few questions and to take in some general advice as I know many of you good folks have had the same problems in the past.
Here are some pics:

 

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Question time

Question 1: In the pic of the switchbox of the circled purple wire, the insulation is coming apart at the rubber boot. Is it okay to just tape it up or should I buy a new harness? I currently put some self vulcanizing rubber tape on it but it looks a little crappy. Bruce suggested that I find some liquid electrical tape.
Question 2: The semiclear protectors over the voltage regulator connections and the harness side connectors have been damaged. Do the protectors come with the new VRs? Where is a good place to buy new connectors?
Question 3: I’ve heard that the grey wire out of the VR goes to the tack. I see that one grey wire is plugged and one goes into the harness. Does it matter which one goes to the tack?
Question 4: What is the brown wire coming out of the port – top cylinder?
Question 5: Is it stupid to replace the stator and trigger if they ohm out properly by the book. I’m not sure if MD Offshore is being too cautious, or exactly why that is their policy. I don’t want to replace good parts but I don’t want to have gremlins either. I think the policy of do it once correctly the first time is what I want to follow but I don’t want to throw money out the window either.
Question 6: Do you guys see anything terrible that needs attention?

 

[corey331]

Question 5: Is it stupid to replace the stator and trigger if they ohm out properly by the book. I’m not sure if MD Offshore is being too cautious, or exactly why that is their policy. I don’t want to replace good parts but I don’t want to have gremlins either. I think the policy of do it once correctly the first time is what I want to follow but I don’t want to throw money out the window either.
Question 6: Do you guys see anything terrible that needs attention?

I will say this. When the stator went out on my old 2.4 200, it took everything with it. I wish I would have just went ahead and replaced everything from the get go instead of buying a stator the first week, putting it on, taking the boat out, problem is still there. Then I bought new coils, plugs and wires, put them on, take the boat out, problem still persists. Then finally bought new switch boxes. Put them on, and it ran like a champ!!! This took me over a month to get accomplished due to the fact that I keep my boat at Cumberland 4 hours away. I wish I would have replaced everything and been done with it in a matter of a couple of hours. The work is super easy to do and I didn't have ANYWHERE NEAR $2600 in it. I am almost positive I had about $200-300 in it and it was super easy to do, just take your time getting the wires right.

If it were me, I would replace everything with new. That way you don't put new switch boxes on it, then maybe in a year or so, your stator goes out and wipes them out and you have to buy new ones again.

I don't know other people feel about this, but I also saved a lot of money by buying Sierra parts where I could. I figured I wasn't running any kind of race motor, so they would be fine and I was right. Boat ran like a champ!!

 

[Jimway]

0. Replenish Adult Beverage (the proprieties must be observed)
1. Tape, liquid insulation, heat shrink, etc.
2. Replace bullitt connectors.
3. Don't think so.
4. Temp sensor.
5. No, but see 5a below.
6. Clean all connections including grounds


5a. Substitute Port switch box for Starboard switch box and see if problem follows the switch box. (this costs nothing but some time) Make sure that both Switch boxes are well grounded. Running them without being well grounded can and will cause the smoke that is manufactured inside of the switch box to be let out into the open which is always detrimental to the Switch box, possibly the stator, and definitely the wallet. CDI manufactures some nice components, in my opinion, should it become necessary to update.
PS: Nice boat

 

[DropTop5.0]

0. Replenish Adult Beverage (the proprieties must be observed)

Done!

 

[DropTop5.0]

5a. Substitute Port switch box for Starboard switch box and see if problem follows the switch box. (this costs nothing but some time) Make sure that both Switch boxes are well grounded. Running them without being well grounded can and will cause the smoke that is manufactured inside of the switch box to be let out into the open which is always detrimental to the Switch box, possibly the stator, and definitely the wallet. CDI manufactures some nice components, in my opinion, should it become necessary to update.
PS: Nice boat

I got up early this morning and swapped switch boxes. I used the original switch box that came from the motor not my takeoff from my 2.4.

Result: I had spark on both banks as I tested with my spark tester. I did not start the motor though.

 

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Alright folks I got her running. I cleaned a bunch of the grounds, replaced the voltage regulators in both motors and it appears to be running well. I ran it in a big tub for five minutes or so (each motor) and then took it to the river. It seemed to run well and had good power but I realize I have a fuel leak. I'll start another thread about that and a trim problem.