Mercury 150 Voltage Reg. PLEASE HELP IAM A NOOB!!

335i101

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Just bought my first boat...very exciting to join the community...however this boat has been a nightmare...

Heres is my main issue (one of many problems, but the one that I am trying to tackle)....

After getting my boat, I took it out on the lake (for the second time-the first time the stator was shot) and noticed the voltage dropping very low. Brought it to a small shop as I was pretty much in the middle of nowhere (trekking home from picking up the boat 12hrs drive). They confirmed the battery was not getting charged and recommended I take it to a Mercury shop.

Mercury shop said the voltage regulator was shot and that they could order/install the next day......4 days later they call and said that they adjusted the idle, but that the voltage reg. was on backorder and they couldnt get the part for a while (I was 12hrs from home and already delayed waiting to get the reg. fixed.....I couldn't wait any longer so I took the boat and heading back to ND.

Anyway, I spoke to the mechanic before I left and he said it is a ..."very easy job, take the cover off, swap out the regulator and hook up the wires." (I have no boat-fixin experience, but do quite a bit on cars, so I never questioned him)

I ordered the part, got it today...left work early, excited to install it and take the boat out for its first run (without breaking down).

I CANT EVEN FIND THE VOLTAGE REG.

I bought the service manual (although it is for 1984-2000 2.5hp to 275) it is not helping me at all.:mad-new:

I think I have narrowed it down to being under the flywheel...but the mehcanic said it was a simple job....I look in the manual and it says I need special tools for protecting the threads, a puller, lining up the timing...etc....??? Is this right???

I have searched youtube, google, read the manual and it is getting me no where.

It is a 1991 Mercury 150. The regulator is part #88825A7. I attached the pic from the service man. it says my part# is item 32....my regulator looks a lot more like item 5 in the pik.

Thanks in advance.....I seem to have zero intelligence when trying to work on this motor.image.jpgimage.jpg
 

335i101

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Re: Mercury 150 Voltage Reg. PLEASE HELP IAM A NOOB!!

Did more searches on stator removed and it looks like that is what has to be done.......just ordered the special puller and the 1-5/16'socket for the flywheel...
 

Faztbullet

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Re: Mercury 150 Voltage Reg. PLEASE HELP IAM A NOOB!!

I ordered the part, got it today.
Post a pic of the part received as you dont need to pulll flywheel to replace rect/reg...
 

carholme

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Re: Mercury 150 Voltage Reg. PLEASE HELP IAM A NOOB!!

If you look at the parts list I sent you in the other post under IGNITION COIL/VOLTAGE REGULATOR (items 5 and 32) the regulator depends on what amp system you have. Item 5 is for the 40amp and item 32 is the 16 amp. If the old one you have is like item 5, then you have a 40 amp system.

Or if you order from CDI for your s/n:

Results | CDI Electronics

Gerry
 

335i101

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Re: Mercury 150 Voltage Reg. PLEASE HELP IAM A NOOB!!

If you look at the parts list I sent you in the other post under IGNITION COIL/VOLTAGE REGULATOR (items 5 and 32) the regulator depends on what amp system you have. Item 5 is for the 40amp and item 32 is the 16 amp. If the old one you have is like item 5, then you have a 40 amp system.

Or if you order from CDI for your s/n:

Results | CDI Electronics

Gerry

Thanks....so I assume that I have the 16amp (based in the serial). The top pictured regulator from your link is what I received for the part. I just can't find we're it goes...

Thank again.
 

carholme

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Re: Mercury 150 Voltage Reg. PLEASE HELP IAM A NOOB!!

Don't understand what you mean, (based in the serial). If you are looking at the s/ns from the CDI site the s/n range is the same for the 16/40 amp systems. They presume that you know what system you have.
In your first post, you said "my regulator looks a lot more like item 5 in the pik." If that is the case, you have the 40 amp system. Where the two regulators are listed in the CDI link, click on the numbers in red and it will show you a picture of each one. The 40 amp is quite distinct compared to the 16 amp.

Gerry
 

335i101

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Re: Mercury 150 Voltage Reg. PLEASE HELP IAM A NOOB!!

Sorry for not be clearer. I have the 16 amp system.

What I meant was based in the schematic drawing the regulator I got from the dealer looked more like item #5.

The link you sent, confirms with me that I have the 16amp system and the correct replacement part. I just can't locate the part on the engine.

(Just noticed that you have been helping me in both my posts, I truly appreciate it)
 

335i101

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Re: Mercury 150 Voltage Reg. PLEASE HELP IAM A NOOB!!

Found my "regulator". Howeimage.jpgver mine has 2 red, 1yellow and 3blk and is a little box.

The replacement has 2yelw, 2 red, and a grey and looks very differant.

image.jpg

So, am I upgrading something or did I get sent the wrong part??
 

335i101

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Re: Mercury 150 Voltage Reg. PLEASE HELP IAM A NOOB!!

Ok I figured out that I am replacing the reg/rec. for the new voltage regulator-made it a lot easier once I knew that.

Anyway a few more questions before I hopefully finish it up.

1) The new regulator has 2 yellow, 2 red, and a grey. *I narrowed it down to the 2 yellows go to the 2 yellow wires from the stator. *The grey goes to the tach. *

BUT THE RED ONES.....I have a thicker red wire that was plugged into the old regulator that goes to the power trim, does that go to the thicker red wire in the new voltage regulator?? *Thus plugging the thinner red wire from the new regulator into the red wire that was originally in the rectifier-(that leads to the starter)????

2) There were 3 black wires that were screwed into the old regulator mounting screws. *The new regulator does not mount very well with the wires underneath it. *Are those just grounds?? *Any recommendation on where to move them??

3) Is that a fuel line that runs to the top of the engine near the regulator? *I cant mount the new reg. without removing that hose....just wanna know what I am removing before I pull it.

4) I am guessing this doesnt apply to me, but the directions for the install of the voltage regulator say, in the last step, "...Grey stripe on OEM stator can be connected to either yellow wire." *I cant find any "grey stripe" and have know idea what they are talking about.*
 

carholme

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Re: Mercury 150 Voltage Reg. PLEASE HELP IAM A NOOB!!

I couldn't find an installation sheet on the CDI site so I think you should contact CDI tech service at 1.800.467.3371, extension 3 and let the service guy know what p/n unit you have purchased and what p/n it is replacing. Have your engine s/n, model number, hp etc handy to assist him. Tell him about the wire colour problem you are having and he will put you right.

Gerry
 

Dukedog

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Re: Mercury 150 Voltage Reg. PLEASE HELP IAM A NOOB!!

Tha cdi won't work with your motor. Its for 40 amp stuff. In fact with proper battery maintance yours will be just fine without any type of regulator especially if ya run several things electric like radio, pumps, depth finders and such. Some of tha early Merc 16 amp motors didn't have regulators from production. Ya might wanna check tha build date stamped on tha block. '91 should of had a water cooled 40 amp system............

Looked at tha pic a little closer. There's something really wrong with that reg and wiring. Its not mounted like it should be and to many wires for it? Looks like some "southern engineerin'" at work...........
 
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335i101

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Re: Mercury 150 Voltage Reg. PLEASE HELP IAM A NOOB!!

I couldn't find an installation sheet on the CDI site so I think you should contact CDI tech service at 1.800.467.3371, extension 3 and let the service guy know what p/n unit you have purchased and what p/n it is replacing. Have your engine s/n, model number, hp etc handy to assist him. Tell him about the wire colour problem you are having and he will put you right.

Gerry

Thanks...I have up, called 2x over 2 days and left messages, nobody returned the call. I towed the boat to a mehcanic and he will look at it in 2 weeks ;(
 

335i101

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Re: Mercury 150 Voltage Reg. PLEASE HELP IAM A NOOB!!

Tha cdi won't work with your motor. Its for 40 amp stuff. In fact with proper battery maintance yours will be just fine without any type of regulator especially if ya run several things electric like radio, pumps, depth finders and such. Some of tha early Merc 16 amp motors didn't have regulators from production. Ya might wanna check tha build date stamped on tha block. '91 should of had a water cooled 40 amp system............

Looked at tha pic a little closer. There's something really wrong with that reg and wiring. Its not mounted like it should be and to many wires for it? Looks like some "southern engineerin'" at work...........

Are you sure? I have a 16amo model it part #is 888258a7. From what I the cdi electronics part will replace both the rectifier and old voltage regulator. Here is the wire schematic.....

image.jpg

(Mine is the 16amp)

This is also the part number a mechanic told me to order.

The wire looks right to me??

Are you sure?
 

Dukedog

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Re: Mercury 150 Voltage Reg. PLEASE HELP IAM A NOOB!!

My bad. Not that familiar with tha cdi stuff. Since it also replaces tha rectifier it will probably work. Original looks like its just "layin" there and not mounted like it should be with two screws (which provide a ground) holdin' it down. But also still think tha '91 came with a 40 amp water cooled reg/rectifier so ya might wanna check tha build date stamped on tha block...........
 

335i101

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Re: Mercury 150 Voltage Reg. PLEASE HELP IAM A NOOB!!

My bad. Not that familiar with tha cdi stuff. Since it also replaces tha rectifier it will probably work. Original looks like its just "layin" there and not mounted like it should be with two screws (which provide a ground) holdin' it down. But also still think tha '91 came with a 40 amp water cooled reg/rectifier so ya might wanna check tha build date stamped on tha block...........

Phew u had me worried. Looks like they made both the 16/40 amp in 91.
 

Dukedog

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Re: Mercury 150 Voltage Reg. PLEASE HELP IAM A NOOB!!

Just never seen a '91 with a 16. That should be what's known as a "fat" block. Late '90 early '91. It LOOKS like a 2.5 on tha outside but can be a 2.0, 2.4 or 2.5 on tha inside. Last of the earlier style blocks was early '90 unless its a "replacement" block. If ya look, stamped on tha block there is a build date. Its at tha bottom of no. 2 cylinder, port side, where tha front half, block half split. Kinda behind tha advance timing arm. 1/4" numbers. M/D/YR. Have ya got a picture of tha port side of tha block? Also tha rear divider plate (where tha coils are mounted)?
 
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Dukedog

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Re: Mercury 150 Voltage Reg. PLEASE HELP IAM A NOOB!!

I just "went ta school"! I'm out in tha shop so I drug out some old microfiche slides and low n behold they did put tha 16 on one. We just never have seen one come thru here at anytime and there's been a lot of 'em over tha years.................
 

335i101

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Re: Mercury 150 Voltage Reg. PLEASE HELP IAM A NOOB!!

Just never seen a '91 with a 16. That should be what's known as a "fat" block. Late '90 early '91. It LOOKS like a 2.5 on tha outside but can be a 2.0, 2.4 or 2.5 on tha inside. Last of the earlier style blocks was early '90 unless its a "replacement" block. If ya look, stamped on tha block there is a build date. Its at tha bottom of no. 2 cylinder, port side, where tha front half, block half split. Kinda behind tha advance timing arm. 1/4" numbers. M/D/YR. Have ya got a picture of tha port side of tha block? Also tha rear divider plate (where tha coils are mounted)?

Boat is at the shop now...sorry no pics.
 
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