Merc XR2 upgrading from rectifier to regulator - advice needed.

[pjbrownva]

Any of the dual 20 amp regs will work, the price differences are mainly quality differences (made in China/Taiwan and such). I’d be real careful with cheapos, in my opinion none of em are real great, you just gotta try and get the least bad. You get one shortin out and before ya know it your stator and wires are burnt to a crisp or even worse a fire. Not a good idea to skimp on them, i would go with quality, in the long run it will cost ya. I would suggest to not use any of the crimp on or bullet connectors supplied with any of em. Any resistance causes heat, then will lead to failure. I personally solder mine in. Also make sure the regulators are bolted up tight and case grounded good. Not sure on this conversion, but a good chance CDI makes a bracket kit to install them like they do for the 16amp conversion, I would check on it for sure.

BTW, I've soldered plenty of wires on boats... I always thought it was the right way to go.
Someone told me that on boats you should NEVER solder, because it creates a rigid joint, and extended vibration can cause a stress point where the solder ends, fatiguing the metal
and causing it to fail. They said you always want to use butt crimps, and adhesive lined heat shrink.

I had never heard that one, but since then have been somewhat superstitiously following that advice. I would think that if you do solder, you at least want to have heat shrink over the connection, to act almost like a strain relief.

Has anyone else heard these theories about soldering wires on boats? I ask because right now I treat it more like a legend that I reluctantly follow hoping that I won't be cursed with electrical issues!

Normally I wouldn't hi-jack a thread like this, but the OP doesn't need this one any more -- (problem solved!)... so I figure it's up for grabs and fair game. ;-)

[tristanlee85]

For reference, I got mine wired up today. No longer seeing the 17V when I rev the engine - now ~13V. I had some spare 1/4" plate, mocked the pattern of the CDI plate, and tapped 4 holes to hold the regulators down. Used some bolts for now, but I have some stainless studs coming Friday so I can Loctite them into the plate and not have to worry about leaks or stripping the threads out of the aluminum plate from over-torquing.

The only wire not used is 1 of the gray (TACH) wires. Otherwise, the 2 red male wires get 12v from the ignition and the 2 red female wire will go up to the post to feed back to the starter.

Pictures in hope that it helps someone else. Thanks everyone for the feedback and sorry Steve2ManyBoats for partially hijacking your thread.

[pjbrownva]

Do you have a picture with how you wired this? I just got mine in the mail today and trying to do the same. My current rectifier has both gray and purple wire coming from it. The regulators only have a gray. But each regulator now has 2 red wires, 4 total since I have 2 regs. Just not sure which wires can remain disconnected.

I assume all 4 reds go to the post that feeds positive back to the starter/battery. Only 1 of the grays should be needed for I assume TACH reading. But I am not sure what to do with this original purple wire.

Sorry @tristanlee85 , I musta missed that you asked about what to do with your purple wire on your conversion.

Truth be told, I don't know. It's been a couple of years since I worked on the electrics, and I don't recall off the top of my head what each wire does.

I *think* that the purple goes to one of the power packs, and if my memory serves me correctly, I think it has to do with triggering the spark somehow... but I could be off.

One thing to note... sorry for not being more specific, but when you hook up your trigger and stator, it actually matters which wires go to which of the switch boxes.

One pair of the wires is marked, usually by being inside a yellow or black plastic sleeve (I think) or on some mota's I think that the one set of wires are a solid color and the "marked" ones have a white stripe. Anyway, you have to put the "marked" wires from both the trigger and the stator to the same switch box.

I didn't know this for *many* years (someone on S&F taught me)... so on some old mota's that I worked on, if I was right, it was merely by dumb luck, and if it was wrong, I never noticed, or I thought I had other issues with the mota.

Just an FYI in case you didn't know. If you really want to learn more, lemme know and I'll search my old posts to find the thread for you. I'm sure it's still buried somewhere in S&F forums.

[pjbrownva]

Oh... didn't see that you got it @trstanlee85. Great to hear!

I actually pulled a wiring diagram, and ... I'm not senile (at least not yet!) there is a purple (or they call it violet) wire from the trigger after all.

Here's a V6 wiring diagram portion as an example. Also note the "yellow sleeve" marker I was mentioning.


And yes, Tristan, you are correct that only one of the grey wires is used for the tach.




For you or anyone else, don't use *this* digram. Get a service manual or use google and pull up the correct diagram for your particular motor!

[tristanlee85]

Oh... didn't see that you got it @trstanlee85. Great to hear!

I actually pulled a wiring diagram, and ... I'm not senile (at least not yet!) there is a purple (or they call it violet) wire from the trigger after all.

Here's a V6 wiring diagram portion as an example. Also note the "yellow sleeve" marker I was mentioning.


And yes, Tristan, you are correct that only one of the grey wires is used for the tach.




For you or anyone else, don't use *this* digram. Get a service manual or use google and pull up the correct diagram for your particular motor!

Sorry, I was probably not very clear. The purple wire I was referring to was coming from my rectifier (not trigger), you can see it in my pictures above. I believe that wire is what gets 12v when the ignition is turned on to "enable" the rectifier. On my new regulators, the wire was actually red so I was confused about where it plugged in, but it goes to the same location that violet plugged in to.

I do need a service manual. All Google images I pulled up around diagrams was like that above where it had the post-style rectifier and not the water-cooled one like my engine was equipped with. It's all squared away now!

[FORBESAUTO]

BTW, I've soldered plenty of wires on boats... I always thought it was the right way to go.
Someone told me that on boats you should NEVER solder, because it creates a rigid joint, and extended vibration can cause a stress point where the solder ends, fatiguing the metal
and causing it to fail. They said you always want to use butt crimps, and adhesive lined heat shrink.

I had never heard that one, but since then have been somewhat superstitiously following that advice. I would think that if you do solder, you at least want to have heat shrink over the connection, to act almost like a strain relief.

Has anyone else heard these theories about soldering wires on boats? I ask because right now I treat it more like a legend that I reluctantly follow hoping that I won't be cursed with electrical issues!

Normally I wouldn't hi-jack a thread like this, but the OP doesn't need this one any more -- (problem solved!)... so I figure it's up for grabs and fair game. ;-)

I have ran into issues with solder in certain instances on automobiles where there is is flex like speed sensor wires moving with suspension or wires in through joint on doors etc. But as long as the wire as a whole can move together I don’t see a problem. I’ve never had one fail yet on a regulator, and yes always use heat shrink either way with solder or splice. On the other hand I have fixed countless wierd drivability problems with butt splices on sensor wires, like when someone changes a connector pigtail , which is why I’m a believer of solder when can and there is no bending or flexing.

[tlwjkw]

pjbrownva.... justa note.. think your friend was refering to "end of wire term", ie: fork and/or eyelet connection on tha solder deal.. a soldered butt splice somewhere in tha length of tha wire will not do that..........

also ANY purple or red/purple on ANY merc is supposed ta be a switched 12v power......

[pjbrownva]

pjbrownva.... justa note.. think your friend was refering to "end of wire term", ie: fork and/or eyelet connection on tha solder deal.. a soldered butt splice somewhere in tha length of tha wire will not do that..........

also ANY purple or red/purple on ANY merc is supposed ta be a switched 12v power......

That actually makes sense about the ends or terminals of a wire. Also, thanks for the info on the purple wires. :-) -Phil

[rgsauger]

@rgsauger , I guess you learned, with an electrical fire, always cut the power first, then try putting it out.


:-) Glad to be free!!!

-Phil

No doubt!!! I didn't know wth was the problem and my bud in a different boat yelled to kill the power on the battery switch. Now that I know...no big deal. The first time though? Chiiiiiiiiiiiit!!!!!

[rgsauger]

My volts were reading around 15.9 to 16.5 or so which should have clued me in that it was going out. Hindsight is 2020

[tristanlee85]

My volts were reading around 15.9 to 16.5 or so which should have clued me in that it was going out. Hindsight is 2020

What batteries are you running? When I looked up info about why my NEW CDI rectifier was over charging, I saw on their site it says not to use maintenance-free or AGM batteries. Both of mine are deep cycle marine batteries. Always have been in this boat. Are they not able to handle the charging current coming from the regulator?

[pjbrownva]

What batteries are you running? When I looked up info about why my NEW CDI rectifier was over charging, I saw on their site it says not to use maintenance-free or AGM batteries. Both of mine are deep cycle marine batteries. Always have been in this boat. Are they not able to handle the charging current coming from the regulator?

@tristanlee85 ,

I looked at your photos, and you're really close, but you're wires still aren't quite right. You need to fix it, even though it appears to work, all four red wires have to be connected,
not just two of the four.

All four red wires go from the voltage regulator to the same terminal on the starter motor solenoid that has the +12V cable connected to your battery.

See the attached diagram, where I drew some red lines to make the key points stand out.

Here's how the system works: Your stator puts out a high voltage alternating current on the yellow wires that goes into the regulator/rectifier.

The regulator/rectifier converts this to a voltage regulated direct current, and puts the current out on the red wires. Then the red wires connect to the starter motor solenoid, where they
can send current to your battery to charge it, or anywhere else current is needed.

Leaving those wires floating isn't a good idea. Each regulator/rectifier can put out up to 20 amps, so the way you have it hooked up now, either (a) one of those wires could be carrying 20 amps, which is way to much current for such a small wire, or (b) you're whole system is limited to 20 amps total (10 amps per rectifier), rather than 40 amps total.

I'm not sure if both reds are just connected together internally or not... or whether the device contains essentially two separate but identical circuits each of which can handle 10 amps, but either way leaving those two red wires floating like that is bad news. You don't want to overload the wires that are hooked up, and you also don't want your charging system creating voltages and trying to produce a current with nowhere for that current to go. Both are bad, and both will at best shorten the life of your components, and at worst create some type of failure or other electrical issues.

The tach wire is an exception... but with only a few exceptions, if you have a wire, it should be connected to something, and if it's not, you want to know what that wire is, what it's supposed to do, and why you're not using it. Otherwise, you are only setting yourself up for electrical problems down the road which sometimes can be intermittent, temperature dependent, and have a host of other factors that makes them difficult to diagnose.

-Phil

[tristanlee85]

That picture wasn't full assembly, mainly just showing the plate and how I mounted them with the wires only partially connected.

That diagram is helpful and make sense. I am not sure if they are 2 different 10A circuits internally. I do know that I was getting 0V on BOTH reds until I finally plugged in the MALE red into the 12V+ switch violet wire that my old rectifier plugged in to, then the FEMALE red was reading ~13V when running. So I am guessing I no longer need to use that 12V+ switch ignition circuit and just run all four reds to the starter solenoid like you mentioned.

[pjbrownva]

Bingo! You're spot on! Run all four reds to the +12V at the starter solenoid, and you'll be good to go!

[rgsauger]

What batteries are you running? When I looked up info about why my NEW CDI rectifier was over charging, I saw on their site it says not to use maintenance-free or AGM batteries. Both of mine are deep cycle marine batteries. Always have been in this boat. Are they not able to handle the charging current coming from the regulator?

Regular ol' group 27'ish marine batteries from Wally world. Works perfectly now with the new reg. About 14.5 is all I see.