TOPIC: Tach wiring - '62 Merc1000

I got three wires coming from my tach to the motor, one to a ground block, one to a small post on my solenoid (power), then one to a post on the rectifier where it gets pulse from one of the yellow wires from the stator.

Question # 1: I want the correct colors from the tach to the motor. Right now I am using trailer wire (brown/yellow/green). What is the correct color for these wires from the tach (ground, power, pulse)?

Question # 2: I have removed the old rectifier and am hooking up a voltage regulator. I know how to do the wiring thanks to Doc Frankenmerc, but wonder if I can hook the pulse wire from my tach to the grey lead from the new voltage regulator?

Question # 3: What else should I do with my old motor while she's sitting in my nice warm shop? Change the LU lube right? Fog the cylinders? What else?

Thanks folks! Happy new Year!

Frank

Can't help with the electricals, but for storage, fog motor, change L/U lube, and get out the grease. Grease the tilt tube and pivot zerks, pop the hood and lightly grease the throttle , shift, and carb linkages. Drain carb bowls if they have drain plugs, run fuel out before fogging if not. I mix a gallon can of heavy oil fuel (20-1) and Seafoam for my last run before storage and run for about five minutes before running fuel out. Done this for 30 plus years, never had an issue in spring- except for a little extra smoke when first started.

Thanks Kerry, but I ran it out of gas last time out, took the drain plugs out of the bottom of the carbs this a.m., nuttin. Carbs look nice and clean, inside and out. I'll fog the cylinders, change the LU lube and do da grease thing.

Frank

Wasn't sure if you did, included it in case, and if anyone else wants to know. Sounds like you are almost done.

Yeah, today or tomorrow I'll finish er up Kerry. Fingers are freezing from washin the pickup in 45 degree weather (and a wind)!

Frank

Frank,
Yes,...The gray wire coming out of the regulator goes to the tach pulse wire which is brown - if it exists in your internal harness.
If you are plugging the tach into the front of the control box your colors at the tach will be:
Brown - pulse (sender)
Black - ground (-)
White - 12v (+)

If you decide to go with '80s+ industry standard colors:
gray - Tach Sender (pulse)
purple - 12v+ (with ignition 'on' only)
black - ground (-)

Thom

I put in an aftermarket tach Doc, no brown wire coming out of my harness. This is straight from the back of the tach. Can pulse from the tach still go to the gray wire from the regulator?

I have power going to a small post on the solenoid, the post near the big one for 12v+. I believe that turns the tach on when the key is on, so I'd do that purple and keep the ground black?

Thanks Thom. Happy New Year!

Frank

frank, no need to pull the plugs and fog each cylinder. fogging thru the carbs accomplishes the same thing. ron

That would work if the motor was running Ron, but it's not. Doing all this on the motor stand in my shop.

Frank

I put in an aftermarket tach Doc, no brown wire coming out of my harness. This is straight from the back of the tach. Can pulse from the tach still go to the gray wire from the regulator?
Yes
I have power going to a small post on the solenoid, the post near the big one for 12v+. I believe that turns the tach on when the key is on, so I'd do that purple and keep the ground black?
Incorrect.
The purple wire will need to go to the ignition 'ON' 12v+ terminal on the primary side of the ballist resistors, which is 'E' Black on the factory wiring diagram.
The (2) small terminals on the starter solenoid do the following: (1) should have a ground strap on it with the other end to engine ground (starter body, etc)
(2) should only have the yellow wire attached from the internal harness. It is the wire that only shows 12v+ when the ignition key is turned past 'on' to the 'start' position as the yellow wire activates the starter solenoid which makes the starter spin.
It doesn't matter which small terminal is assigned to these 'tasks'. One does one task and the other does the other task.
Thom

Excellent! Thanks Doc! You da man. Now I can get what I need and do this baby over correctly.

Take care and best of luck in da new year.

Frank

12v to this post?

Not correct Frank.
See the attached picture.
Thom

I'm real confused then Doc, but that's not new. I thought that block was a ground block, but it has a red or orange wire going to it. The middle screw is where the ground from the hood attaches.

No matter, I'll wire the tach 12v into where you say it needs to go. Thanks for the help, I appreciate it.

Frank

Frank,
It is not a grounding block - it is just a terminal block where wires from the internal harness connect to wires that go out to other components.
The rusty screw at one end and another one in a like position at the opposite end do thread into the engine block and 'could' be used as a (-) ground terminal if desired, but the (3) screws in a row that all have wires on them only thread into the plastic - not clear through to the engine block.
The center wires (blue)that you said is the ground for the top hat are actually the momentary 12v+ to operate the electric choke solenoid (up in the top hat)when the choke button is pushed down. One blue wire comes to that terminal from the internal harness and then connects to the blue that goes up in the hat (choke solenoid).
The actual ground for the top hat (which is required so the electric choke can have a decent ciruit) is usually a braided ground strap that is fastened to one of the retaining machine screws (phillips head I think)that holds the choke solenoid to the top hat and the other end of the ground strap goes over to one of the (2) cap-screws that holds the timing and idle stop adjustment plate onto the top area of the distributor housing.
Thom

Thanks Doc, that does make sense, especially seeing that my choke works fine. Also, the braided ground strap that went from the idle stop adjustment plate to the hood mount on the forward port side disintegrated on me, and I replaced it with a piece of 10 ga. wire a while ago.

I might have some purple wire around from when I built the hot rod, but I bet not enough for the length I need. That will be the next challenge!

Frank

Frank,
Although purple is the designated color for industry standard 'ignition on 12v+',...Red is readily recognized as 12v+ as well - just suggests constant 12v+.
Since this is your toy and you are the wrench as well, red could be acceptable IMHO.
Thom

Thanks Thom, but good old NAPA has purple wire. I've already ordered a roll of 14 ga. Don't mind me, I just like using specific colors. There's other red stuff going in there, so this way I don't get confused. Seems to me I used used gray for pulse and purple for 12v+ for the hot rod tach as well.

Also, I will find a 3 prong plug so I can have a harness that stays with the motor when I want to pull it. That's what I did with the "old" tach wiring.

Frank

Hi Frank,
I'll try and help now. The tach you are using sounds like it is set up to read pulses from a 12 pole stator. I do not have an early stator in front of me to count the poles but beware that there are two size stators used on the early 1000's so you should check to see what you have. I'll look tonight as I have both sizes and I can count the poles on both of them. This tach may not work at all dependng on pole count. These tachs are typically used on thunderbolt style ignitions which you do not have. So you made need a different tach if pole count is wrong.
That said, if the stator is a 12 pole then it will work. A typical plug in Merc tach has three wires but the +12 is only there to light the bulb. The other two wires are for a good ground and one to either wire (yellow) from the stator. Some aftermarkets only have two wires (no light).
If you have a three wire tach it may be 12 volt is needed similar to a Merc tach for the bulb OR possibly it is for tach function in either case you should have this to a switched 12 volts that is either "off" or "hot" while cranking and/or running. The + 12 feed to the resistors is such a place to pick that off.
Use a voltage meter and verify that is what is supplied and switched correctly. Keep in mind if the 12 is only for bulb function then you don't need it.
Randy

Randy, this tach is installed and works. I am just "cleaning up" the wiring. I bought it specifically for my old '63 Merc, and it did the job all summer. Actually it fits a number of outboards, depending on how you set the dip switches in back, but it had a specific position for my motor. I just noticed, I mistakenly put '62 in the subject box, but my motor is a '63.

If anybody wants to know the brand and model, let me know and I'll post it here.

Thanks!

Frank

Can I use this mount both as a ground for the voltage regulator and as a junction for the 12v+ wires? I don't think so, but want to be sure. It would work so well if I could!

I tapped a 10-32 hole on top where you see two 10 ga. red wires loosely attached. I still need to run the two from the voltage regulator there, but don't want to do it till I know for sure if this would work or not.

I didn't have the right size bolt to attach the regulator, but will pick one up soon. It is hanging where it will be mounted.

What do y'all think?

Thanks!

Frank

Regulator??? The early sixes had no Regulator. Not enough output from the alternator to fry the battery so it is an open charge system.
Maybe there is something I don't understand about what you are doing.
Randy

Randy, I'm replacing the rectifier with a voltage regulator for constant voltage. It relates to a problem I ran into this summer, and seemed a more than reasonable fix. It's not a big deal, but I was hoping for someone to tell me whether or not I can use the same post for a ground for the new regulator as I'm using for a 12v+ junction.

Frank

i think he is talking about a rectifyer.

Frank is using a regulator with a built-in rectifier off a later model Mercury O/B.
Although the stator may not put out the AMPs that this regulator will handle,...It will control his stator output voltage to 13.8 rather than allowing it to spike to 17.5 +/- vdc.
This is a great retro-fit for use with today's batteries and other resistance issues.

Frank,
I don't know what those red wires do for a living,...BUT you can NOT use that bracket as a terminal block for 12v positive (+) connections.
It will be just fine as a negative ground (-) terminal block and place to mount the regulator and its black (-) ground wire,...Provided the regulator is secured off to the side of the hole that the face place needs to go through and secure itself.
Thom

Thom, as you may remember, this regulator does not have a black ground wire. It needs to mount to something that is ground.



I figured this face plate mount would do da trick. Also, the way the VR is shown in the pic in my last post is the way it has to mount so it does not interfere with the face plate

I didn't figure I could us the mount as ground and a 12v+ block, but it was just an elegant and clean approach. How about if I installed a nylon washer or two to prevent contact?

I can take that 8 or 10 ga. red wire that comes from the wiring harness for the controls and was attached to the side of the rectifier straight to the big positive lug of the starter solenoid right? (That would be a good solution too! If not there, where would be good?) I know I attach the two red wires from the new VR to the big positive lug of the starter solenoid.


It's nice not to be in a rush. Probably can't go boating for a few months.

Not much left to do here, then I can just clean the old tower or power up and cover it till it's time to re-install. All I'll need is a bag of 50's for gas the way it's sounding!

Thanks again for all the help Doc.

Frank

Frank,
Yes,...You could drill that hole out enough to slip in a nylon sleeve for your machine screw to pass through, and add a nylon washer to either end of the nylon sleeve and then use that as an insulated terminal for 12vdc(+).
Rather than use a terminal block (which can over time become a point of corrosion and resistance) I think you would be better off to simply put both of the red wires coming from the regulator together in one end of a butt connector and then run one 12ga from the other end of the butt connector to the big red primary on the solenoid.
I forgot that your new regulator (Sierra Marine?) doesn't have an external ground wire and simply needs the regulator housing to be grounded.
T

Thom, I can run both red wires from the new VR together in a ring terminal and easily attach it to the big positive lug of the solenoid. That's not a problem.

My question is, can I run that big gauge red wire from the wiring harness that used to be attached to the side of the rectifier to the big positive lug on the solenoid?

Sorry to keep bugging you on this, but I am a firm believer in asking questions (as you've no doubt noticed). I just want this to be done correctly.

Once I get this done, it's back to tach.

Thank you again for all the great help!

Frank

Let me say I may not understand exactly what/how you are installing this as there must be sme things missing from the thread. Plus I am not taking issue with the VERY knowlegable people on the board.
But a few things come to mind. The comparible Merc rectifier/ regulator would be the three wire version on the say mid 70's Merc 6 in line. Why not use one of those? The multiple wires you have look like the style that would control the field strength, thus the output, like in an automotive alternator. The Mercs of this ilk have fixed magnets and no control of output this way is possible. I may be mistaken about what you have there.
Second, I would note that actual spark voltage is directly proportional to primary voltage. Your Battery voltage is stepped down through the resistors but keep in mind on these motors the voltage will increase as RPM increases so even with this stepped down voltage the coils will still see a higher primary voltage as RPM picks up so the spark gets hotter at higher RPMs because of this. It gets harder to fire a spark plug as RPM increases so I would think this increase of voltage is a big help in keeping the plugs firing happily as RPM increases. None of this is true on a Thunderbolt ignition but, you have points where it is true. I don't think it coincidental that points motors had no voltage regulator but the Thunderbolt ignition did. There were two overlap years where you could get a 6 with or without thunderbolt as it was offered as an option on the SS models. If Thunderbolt then it had the regulator, if points no regulator. Same Flywheel/magnets and stator were used for both style ignitions.
If you are trying to run something on the boat that needs 12 volts and does not like to see higher voltages I would regulate the supply just ot to that device rather than try and regulate the whole charging circuit. You can find regulator circuits that will splice in for this purpose. In the old days pretty much light bulbs was it as far as other things being powered and they did not care if they saw higher voltages.
Again my two cents and I may have a gross misunderstanding of what you are doing.
Randy

Randy,
First let me say that I always find your posts are based on a LOT of experience and great understanding of these beasts and I know that you are certainly qualified to call me on this.

When concerns with the battery voltage being 'charged' up to 17.5 vdc +/- was discussed a few years back and primary blame was put on the cheaper designed batteries on the market,...It was suggested to me that by installing the Merc regulator (with a rectifier built in) that the voltage from the stator coming out of the original unregulated rectifier could be controlled to a consistent 13.8 vdc as it returns to the battery so that the battery won't over-charge, get hot, spike, or fail.
Consequently controlling the 12 vdc (or 13.8 vdc) at any RPM being supplied to - in this case - the ballist resistors that step the voltage down before going on to the coils/points.
It also controls the voltage to 13.8 vdc as it leaves the battery or harness heading everywhere else in either the internal harness related wiring or the hull's electrical components.
I've been installing these regulators on the dual point Inlines as well as the solid state Inlines for a while now.
Granted, there is a much greater problem with uncontrolled voltage from the larger stators found in the later inlines, but it seems to work fine on the older 6 amp or 9 amp stators.
Granted, the tach wire (gray) won't be very useful if an older stator isn't a 12 pole.

If you know of a reason that this should not be done or if it can actually harm something - please guide me to the light.

Frank,
I still say to tape off the #10ish red wire and go direct to the primary 12vdc on the solenoid from the regulator.
Thom

Thom, my stator is a 12 pole right? If in question, just tie pulse from the tach to a yellow wire?

I'm getting there! Thanks!

Frank

Hi Frank, Thom,
I'm not trying to be a busy body, I just know how hard Frank has worked to get this far, I have followed his trials and tribulations and would hate to see something melt down due to
mis-wiring, it was in the spirit of covering all the bases as to what this change would do rather than offering an opinion against.
I would trust anything you (Thom) have done implicitly and I want Frank to have the boat be all it can be. We all have a deep affection for those 6's and it's great to see so many people wanting to keep them going. This board is tremendous for sharing info as the knowlege base has pretty much dissapeared from the Marine market place so it is us who band together under the common cause that will keep them running....
Damn-it I wish we were all closer!
Randy

Thanks Randy, but I have bugged Doc continually such that I have great advice on wiring. It's really just this voltage regulator thing, I don't want to screw up!

If anything is mis-spelled here or whatever, gimme a break, I just had my annual eye exam, eyes are dilated, I can barely see. I'm not gonna go wire ANYTHING!

Frank

And,...I went out and checked a very original stator on a lump of scrap barely identifiable as an early dual point 1000 shorty.
The stator in this case is a (12) pole.

Randy,
We ARE closer than we were 15 years ago via the WWW. It has opened the door to such forums as this where info and experiences can be shared in a dedicated effort to keep the old Stacks alive and healthy.
There is nothing cooler than being at a boat launch or out on the water and having someone approach and tell a story relating to a Stack and boating in their family history.
Not to mention prop-walking past the new junk that folks have their 401K invested in with one of our low budget Stacks!!!
Thom

You sure are a lucky guy Doc to have all that beautiful water to hang out on. I never shoulda left WA state...

Frank

Frank I would like to throw my two cents in I would put a circut braker in the red output of the reg. so if it shorts out it will not burn every thing up Harley started doing that and I am planing doing it to my 650
Charles

Frank I would like to throw my two cents in I would put a circut braker in the red output of the reg. so if it shorts out it will not burn every thing up Harley started doing that and I am planing doing it to my 650
Charles

Frank I would like to throw my two cents in I would put a circut braker in the red output of the reg. so if it shorts out it will not burn every thing up Harley started doing that and I am planing doing it to my 650
Charles

That's an excellent idea Charles, but it's like 6 cents...

Would 20 amp be good? 15? 25? Any idea?

Frank

I would start with a 15 amp since it is only 9 amp alt
Charles