2.0 Liter 150 producing to much voltage?

[jsnvulcan13]

Yesterday I noticed that my volt gauge keep creeping up to 16 volts. If I bumped the trim the voltage would drop but it would slowly creep back up. Someone told me that the problem is the rectifier. Can some please share any knowledge on how to troubleshoot the rectifier? I do have a VOM. If the rectifier is bad who should I buy it from? I live in East Houston.

Thank
Jason H.

[CKMATE225]

I doubt its the rectifier, maybe a regulator. How old is the motor? Some of the older ones (like mine, it dosent have a voltage regulator) will hit 17v to the battery at High RPMs.
There is a test you can do with a ohm meter on the rectifier but I dont think thats your issue. If you rectifier was shot you wouldn't be charging at all.
It has nothing to do with regulating voltage,. Just turning AC into DC.
You may not even have an issue. But someone with a regulator motor may chime in.

[capnzee]

On the back top side of the engine(right behind the fly wheel) you will see a voltage regulator. It is about 2 inches square and has 2 wires (I believe they may be red and yellow). See if you can't swap one out with someone, it only takes a few minutes to change one.

[jsnvulcan13]

I doubt its the rectifier, maybe a regulator. How old is the motor? Some of the older ones (like mine, it dosent have a voltage regulator) will hit 17v to the battery at High RPMs.
There is a test you can do with a ohm meter on the rectifier but I dont think thats your issue. If you rectifier was shot you wouldn't be charging at all.
It has nothing to do with regulating voltage,. Just turning AC into DC.
You may not even have an issue. But someone with a regulator motor may chime in.

I believe the motor is a 1990.

[CKMATE225]

Ok, On a 1990 2.0 I think you should have a 16 amp charging system with a single voltage regulator. do you only see the higher voltage at high rpm?, I ask because I dont think the voltage regulator you "need" Is availible anymore,But you will have to look that up with your serial #.
The battery will act as a voltage regulator to a certain point and unless you are out on the water blasting at WOT for hours everyday you probabaly wont have a problem. I guess you could retro fit a different regulator into the system if you really need to.
But if you want to burn some electricy turn on the lights and crank up the music have a good time.;)

[jsnvulcan13]

Ok, On a 1990 2.0 I think you should have a 16 amp charging system with a single voltage regulator. do you only see the higher voltage at high rpm?, I ask because I dont think the voltage regulator you "need" Is availible anymore,But you will have to look that up with your serial #.
The battery will act as a voltage regulator to a certain point and unless you are out on the water blasting at WOT for hours everyday you probabaly wont have a problem. I guess you could retro fit a different regulator into the system if you really need to.
But if you want to burn some electricy turn on the lights and crank up the music have a good time.;)

I would not consider it high rpm probably around 4,000. Just cruising with the wife and kid.

[WATERWINGS]

subscribed

[capnzee]

There must be a million Merc outboard dealers with parts around and can supply you with a used voltage regulator. You have to do a little "digging" for yourself. In the mean time, if your boat battery is not "bubbling" over and spilling acid from the overcharge, I wouldn't worry about it. The key is, you just gotta do a little "digging" for yourself. You can also go on S&F parts wanted, type in what you need and I am sure some one will respond. Rod

[CKMATE225]

What are you getting at idle? You probably arn't getting much more than 12.5v if you have a multimeter you can get an acurate reading right off the battery, But still, I dont think you have anything to worry about though, Worst case if your regulator was shot, you may shorten the battery life slightly.
You could look around here and see if anyone has a regulator that you could buy and give it a shot and see if it makes a much differance. But 15-16V at crusing speed isn't really going to hurt anything. This charging system isnt like a car that can maintain 14.5 v all the time, it will vary with rpm.
Anyway... Go out and run the boat and have a good time dont worry about it.:):)

EDIT...Sorry Capnzee, I see you posted just before I did, I don't want to seem like I was repeating what you just said.

[tlwjkw]

'90 should have a water cooled 40 amp I think...........

[CKMATE225]

I believe in 90 they transitioned from the 16 amp to the 40 amp. I assumed he had the 16a.(My mistake) But I suggested he look up the parts by the serial #, Because in reality,.. I dont think actual model year makes a whole big bunch of differance, Thats why you always need the numbers when you buy parts.

[TEXAS20225]

I believe in 90 they transitioned from the 16 amp to the 40 amp. I assumed he had the 16a.(My mistake) But I suggested he look up the parts by the serial #, Because in reality,.. I dont think actual model year makes a whole big bunch of differance, Thats why you always need the numbers when you buy parts.

they were both available 16/ 40 amp in 90/91 according to Mernet in any case regulator are NLA for the 16 amp but i have used ones . there have been countless 150 /2.0 Mercury motors that have burned bazillions of gallons of gas with no regulator run it dont let it rent any space in your head

[wrechin2]

there have been countless 150 /2.0 Mercury motors that have burned bazillions of gallons of gas with no regulator run it dont let it rent any space in your head

:iagree::iagree:I normally leave them off. I have never had any issue with them. That is why you are suppose to run a non-maintanance free battery on it. Even the old in-lines would get around 16V at WOT. Just my .02

[capnzee]

:iagree::iagree:I normally leave them off. I have never had any issue with them. That is why you are suppose to run a non-maintanance free battery on it. Even the old in-lines would get around 16V at WOT. Just my .02 Just a note here, do you mean a maintenance free (sealed) battery or a battery that requires periodic service?

[jsnvulcan13]

they were both available 16/ 40 amp in 90/91 according to Mernet in any case regulator are NLA for the 16 amp but i have used ones . there have been countless 150 /2.0 Mercury motors that have burned bazillions of gallons of gas with no regulator run it dont let it rent any space in your head

You state that you have plenty of used regulator if I wanted to buy one how much do you want for one shipped to Houston?

Jason H.

[TEXAS20225]

Although Mercury No longer has this regulator Promarine has a after market Reg. part number #5279 it sells for about 120.00 plus shipping if you want a new one:thumbsup: 1/2 of that for a used one( maybe you should buy a new one )

[wrechin2]

Just a note here, do you mean a maintenance free (sealed) battery or a battery that requires periodic service?

You are not suppose to use a sealed battery (maintenace free) on marine engines as very few actually have regulators and will run around 15V-16V at WOT.

[wrechin2]

Not to cut you out Bobby, But If I can find one tomorrow, you can have it. Just pay for the shipping. $5 will cover that.

[TEXAS20225]

no problem he seemed like a man wanting to get a problem fixed new is always better to buy new electrical i dont generally mess with stuff like that any way

[bobkyle2]

Not to cut you out Bobby, But If I can find one tomorrow, you can have it. Just pay for the shipping. $5 will cover that.
im new hear... not to hi jack this thread... but that statement^^^ is why i have fell in love with this site.. been to many other boating related sites... just didnt feel like home

[wrechin2]

I took one off just the other day when I rebuilt a 2L and I don't run them and never had a problem. I will more than likely just throw it away. At least this way it may find a good use.:thumbsup:

BTW, how ya been Bobby??

[TEXAS20225]

James ive been OK or as well as can be expected at 65 :rolleyes: some day i want to get on the phone with you and you explain in a simple way how the switch box double fires my pea brain cannot absorb that process yet and im sure it may have been a problem on a couple of motors this year right now i have a XR4 that doing something strange its rebuilt all .015 over new pistons carbs overhauled 2 wire water cooled 40 amp system at idle it revving up on its own a couple of hundred RPMS for some reason:confused::confused::confused::confused::confused::confused: no air leaks at case half or carb gaskets im not sure what cooking yet

[tlwjkw]

Although Mercury No longer has this regulator Promarine has a after market Reg. part number #5279 it sells for about 120.00 plus shipping if you want a new one:thumbsup: 1/2 of that for a used one( maybe you should buy a new one )

Bobby, he needs to put up a pic. If its a tru stock '90 model powerhead its gonna be 'bout 99 ta 1 thats is a water cooled 40..............

[TEXAS20225]

Tommy i just looked it up again 90/91 with serial numbers 0C0239xxx thru OD0871xxx had both regulators listed in parts list ???? i guess if he gets the wrong one he will know then what he has

[TEXAS20225]

Tommy you know the 2.0 liter i just sold to Joedon was a 16amp system it was a 1990 stamped on the block memba ;);)it was your mota you bought it for the parts off it came from Denton it had a bad hole i sleeved it and rebuilt it

[wrechin2]

James ive been OK or as well as can be expected at 65 :rolleyes: some day i want to get on the phone with you and you explain in a simple way how the switch box double fires my pea brain cannot absorb that process yet and im sure it may have been a problem on a couple of motors this year right now i have a XR4 that doing something strange its rebuilt all .015 over new pistons carbs overhauled 2 wire water cooled 40 amp system at idle it revving up on its own a couple of hundred RPMS for some reason:confused::confused::confused::confused::confused::confused: no air leaks at case half or carb gaskets im not sure what cooking yet

Call me anytime! 423-304-0930. I have found more bad boxes this year than I want to remember. Every mercury engine gets them when I build them. I have converted several of the 2 wire 40 amp systems ( all been XR4's) to 16 and 9 amp. It may be one that has been converted or the 2L may not have it. Never given it any thought or looked into it!! Things that make you go huh....

[tlwjkw]

Tommy you know the 2.0 liter i just sold to Joedon was a 16amp system it was a 1990 stamped on the block memba ;);)it was your mota you bought it for the parts off it came from Denton it had a bad hole i sleeved it and rebuilt it

It also had a block off plate where tha water cooled reg was supposed ta be............

[jsnvulcan13]

Bobby, he needs to put up a pic. If its a tru stock '90 model powerhead its gonna be 'bout 99 ta 1 thats is a water cooled 40..............

Here is 2 pics.

217624217625

[TEXAS20225]

Tommy i memba the block off now may still have it them 40 amp water cooled are not so hot not to mention a 400.00 regulator the one i just built has it (XR4)

[TEXAS20225]

James have you found any use for the 2 yellow wire 40 amp stator if so let me know i have 6 good ones if there is such a thing

[tlwjkw]

Got some good news and some bad news. Which one do ya want first?

[sschefer]

1990 did have the block off plate on the divider for the 16's and used a rectifier on the electrical plate with a voltage regulator mounted on top of the back of the block by the advance module. You can throw both of them away and just put a CDI rectifier/regulator on it (120-140 bucks). If it's a two wire 40 then it's almost cheaper to get the conversion kit from CDI and put the 4 wire with the dual regulators on it. Runs about 500.00 if I remember correctly. I usually just throw it all away and go new including switchboxes and it runs me around 1200.00. Saves a ton of headaches chasing gremlins.

[TEXAS20225]

of coarse i want the bad i have no use for good news

[tlwjkw]

Not for you, its for jsnvulcan13. Look at tha pictures of the '90 model......

[TEXAS20225]

yeah i asked him if he was sure it was a 90" 89 up are 1 pc heads , i think you know more then i do about that

[TEXAS20225]

Guess who got a new DVA today.:cheers: yeah i never made it to the lake today i spent the afternoon de-wireing the laser and moving stuff that was on the wrong side of the boat:D:D:D:D:D:D:D:D:D:D:D:D:D

[jsnvulcan13]

Got some good news and some bad news. Which one do ya want first?

I am waiting.

[sschefer]

1988-1990-1/2 were transitonal years. 90-1/2 - 91 was a wierd year where a bunch of make do mods were done like the cover plate, voltage regs, etc. 92 thru 94-1/2 ironed some of that out but by 95 the standard was pretty much set and most of the changes pretty much stayed the same right on through 2000. I've worked on all these years and it's a nightmare if you want to try to stay 100% factory. Fortunately, in most cases, you can just upgrade to the 95 changes and be fine.

[jsnvulcan13]

So according to the pictures what year model powehead do I have????

[tlwjkw]

I am waiting.

Good news (maybe, reg. price) is its a 16 amp. Bad news is its probably an '87 or older......

Clamp, cowl and trim is newer but tha powerhead is not a '90 model.......

90% of late '89 and up were 40 amp. Most two piece heads were gone by tha end of '88...........

Motor has a build date stamped at tha base of number 2 clyinder on tha block half, kinda behind tha timing advance arm. Will be 1/8" numbers m/d/y. Might be kinda hard ta read but will be there..................

There ya go...................

[sschefer]

Good news (maybe, reg. price) is its a 16 amp. Bad news is its probably an '87 or older......

Clamp, cowl and trim is newer but tha powerhead is not a '90 model.......

90% of late '89 and up were 40 amp. Most two piece heads were gone by tha end of '88...........

Motor has a build date stamped at tha base of number 2 clyinder on tha block half, kinda behind tha timing advance arm. Will be 1/8" numbers m/d/y. Might be kinda hard ta read but will be there..................

There ya go...................

Yup, that pretty much sums it up. CDI sells the rectifier but that regulator was probably an add-on, maybe not, dunno for sure. Not sure if it's wired in correctly or not. I've seen where they take one yellow off the rectifier and put it on the regulator and then bring the regulator red back to the battery but they leave the red from the rectifier on the battery + at the engine. This does no good at all.

Your simplest fix is with a CDI 16amp rectifier/regulator pack. Just swap wire for wire paying attention to color code and you're good to go. Oh,, there will be two reds, they get tied together at the battery positive terminal on the starter solenoid.

[wrechin2]

I could not find the regulator. I will keep looking for one.

[wrechin2]

I found one if you still need it!!!!

[jsnvulcan13]

Sure I will take it. Do you want me to pay pal you for the delivery?

[wrechin2]

That will work. I will PM you with the details......