Voltage Regulator installation question

[hughesmongous]

I am installing a voltage regulator in a 1998 200hp mercury efi and i see there is 2 that i have to replace but i dont think they are both bad. I would like to know how to test them to see which is bad or if both are. I have little experience with a multimeter so can you explain what i have to set it to complete the test. Also i see that the upper regulator has the grey wire is capped off and in the wiring diagram the lower one is. Does this make a difference which one is going to my tach? Next. does it matter what yellow wires on each regulator i connect to the the others coming out of my stator, or can i connect any yellow to any yellow? When i ordered the new regulator it said that the black wire is no longer used because they use some kind of past behind it, so what is that stuff called and what do i need to do to get it right when installing so that i dont blow my regulator. I have taken boat motors to 5 different mechanics around me and every time i am screwed by there work or lack of. I have given up on taking my motor to people and will just do things myself to insure that they are done correctly so if anyone could help me out that would really be appriciated. Thanks, jason

 

[Fun Times]

The following link offers really good directions for testing all your outboard ignition, voltage, electrical needs,

http://www.cdielectronics.com/support/

 

[gm280]

hughesmongous, first thing first... :welcome: to iboats.Great to have you aboard...

The very best thing you can possibly do is buy the manufacture's model, HP, year specific shop manual for your engine. Not some aftermarket version but the real shop annual. It will have tons of info as to how to test things on your engine and what to expect as results. That will help you understand everything concerning your engine. As for how to test voltage regulators, unless you really understand how to use a volt meter and interpret the readings, it is really difficult to explain how to test them on here. You can read the output while the engine is running, or you can setup a testing power supply and read the output on the bench. But you really have to understand what is going on with them to verify what is happening. JMHO!

 

[hughesmongous]

Thanks guys both were helpful but neither answered the other questions I had about if the grey wire on only the top regulator is supposed to go to tachometer or can it be either, and what compound I'm supposed to use behind it.

 

[sam am I]

I am installing a voltage regulator in a 1998 200hp mercury efi and i see there is 2 that i have to replace but i dont think they are both bad. I would like to know how to test them to see which is bad or if both are. I have little experience with a multimeter so can you explain what i have to set it to complete the test.

Yes, ONE simple way could be to have only one regulator hooked up to the motor at a time. So, fire up the motor with one particular reg. wired in circuit properly, wait a tad, and check the battery for around 13.5-14.5 volts DC with your meter on DC volts. Unhook those two particular yellow stator wires to that reg. and hook up the other two particular yellow stator wires to the other reg's two particular wires , rinse, lather repeat.

Side note......... Both regs. outputs are as wired, electrically "OR'd" and provide 20 Amps. each for a total 40 Amp. system.

Also i see that the upper regulator has the grey wire is capped off and in the wiring diagram the lower one is. Does this make a difference which one is going to my tach?

No, both do the same exact thing, consided one a spare.

Next. does it matter what yellow wires on each regulator i connect to the the others coming out of my stator, or can i connect any yellow to any yellow?

They come in pairs (both the stator and the reg's obviously) , so no. Just use one yellow stator pair and the other yellow stator pair to whichever reg. pair.

When i ordered the new regulator it said that the black wire is no longer used because they use some kind of past behind it, so what is that stuff called and what do i need to do to get it right when installing so that i dont blow my regulator.

past = paste? Well if I understand this statement/question properly, your asking two things...The black wire though is a ground wire and you may leave it unconnected due to the body of the regulator is also ground and you can simply bolt through it's flang's to the block studs, that provides for the proper ground. BUT, if you use "thermally conductive heat sink compound" and mount the regulator otherwise with the compound squished between the reg. and the block, etc., you have to use the black wire bolted/screwed to the block as well to provide/insure for a proper ground due to the heat sink compound possibly impeding a solid/proper ground. Personally? I do both, run the bolt through the ring lug and bolt the black wire into the mount. Keeps it tidier.

I have taken boat motors to 5 different mechanics around me and every time i am screwed by there work or lack of. I have given up on taking my motor to people and will just do things myself to insure that they are done correctly so if anyone could help me out that would really be appriciated. Thanks, jason

Seems to be going around more and more these days eh? Can't say I blame you..........but get AND read a manual too as suggested!!

GL

 

[GA_Boater]

The heat sink compound Sam I Am mentioned can be found at most computer stores. And don't skip it! It helps transfer the heat produced by the regulator to cool it and without the compound the reg will overheat and burnout.

Welcome to iboats, too.

 

[sam am I]

The heat sink compound Sam I Am mentioned can be found at most computer stores. And don't skip it! It helps transfer the heat produced by the regulator to cool it and without the compound the reg will overheat and burnout.

Welcome to iboats, too.

Yes, but obviously applicable ONLY if the mounting arrangement provides for using the compound with a heat sinking surface. Most don't anymore,(think it was a pre-90's, Duke?), they're stood-off with the mounting studs (mine is anyway) and are now air cooled(hence no real need to connect the black wire that OP inquired about).

Think they found that heat sinking them down to the block that can be/had even hotter water flowing through actually made them hotter and fail more often. Things may have changed though with his 98, IDK.

 

[gm280]

Well if one regulator is controlling a 20 amp source, I can understand them getting hot and popping like popcorn. Most systems are usually a 5 amp setup not much more. But 20 amps is a lot to regulate without a good heat sink... That extra voltage/current has to go somewhere, and being shunt type regulation, it gets turned into heat!

 

[sam am I]

Well if one regulator is controlling a 20 amp source, I can understand them getting hot and popping like popcorn. Most systems are usually a 5 amp setup not much more. But 20 amps is a lot to regulate without a good heat sink... That extra voltage/current has to go somewhere, and being shunt type regulation, it gets turned into heat!

Concur and these do/can indeed run pretty warm as they are still in fact, a simple linear shunt reg. on the mag.

Do what Tom Bodett always says, "we'll keep a light on for you"...........keepn'um loaded somewhat helps them last longer as the shunt(SCR transistor typically ) then work less hard, but not too loaded of course as the stator now screams. Find/run as much as ya can that sweet spot in the middle ground somewhere optimizes both systems(reg, stator) MTBF's.

Side note two, there are some shindengen mag regulators out there (primarily three phase made for motorcycles) that feedback from the secondary and open the current path/ground reference in the mag's primary side on a cycle by cycle basis. Thus when hooked to a battery, integrate over time to a smooth cool well regulated 14VDC

I best stop posting so much.....my post count is going up/real life is going down and my head is starting to swell.

Later and GL OP