1973 Mercury 1500 I-6 with 65' or 66' Ignition Components?

[teletekman]

Re: 1973 Mercury 1500 I-6 with 65' or 66' Ignition Components?

Well I went ahead and bought that distributor & coil I mentioned. I check the number on the coil 46307 and it matched up to the one you recommended so hopefully I'll make out ok there.

The only thing left I need **crossing fingers** is the switch box.

 

[teletekman]

Re: 1973 Mercury 1500 I-6 with 65' or 66' Ignition Components?

Ed,

Sorry for the multiple questions on this but Im hoping this will complete my needle in a haystack hunt here. Im comparing the switchbox that I linked to earlier which you stated was for a 4-cyl 80hp which the description did say but I looked up another box and it says it covers them all up to a 150hp I6.

Mercury Outboard Switch Box 332 2986 Fits 65 80 85 90 110 125 135 140 150 HP | eBay

The previous box was a bit cheaper and I do believe I have the single style wire (old style) tach. I'll have to double check that. So will this not work for me? I am trying to get this as inexpensive as possible to make sure this motor will pan out for me and if it does, next year I will upgrade my ignition to the CDI electronics brand.

 

[79Glastron]

Re: 1973 Mercury 1500 I-6 with 65' or 66' Ignition Components?

That switchbox will work with the other items you bought. BTW, keep your old points setup, someone will need.

 

[teletekman]

Re: 1973 Mercury 1500 I-6 with 65' or 66' Ignition Components?

Thanks. Yes definately, I am learning by the minute how much like gold these old parts are becoming.

 

[emckelvy]

Re: 1973 Mercury 1500 I-6 with 65' or 66' Ignition Components?

Glad you found some good deals on the parts, that was a much better price on the coil!

On the switchbox, either 4-cyl or 6-cyl box will make sparks, doesn't matter if used on a Four or Six. But if you were to use a 4-cyl box on a Six, or a 6-cyl box on a Four, the OEM Merc tach won't read correctly.

Unless you've got a Mercury old-style tach, you'd connect the tach sensing wire to the rectifier. This will be a brown wire coming from the motor's internal wiring harness.

Note that with your strange setup, you might find the brown wire connected to one of the twin-coils, as this would work with a car tach set on 6-cylinders.

If you have the old Merc Quicksilver tach that goes to the box, you'll need a new tach. Unless, of course, through luck-of-the-draw, the switchbox you get is for a 6-cyl motor. Usually, a 4-cyl switchbox will have a big "4" sticker on it, and a "6" sticker for 6-cyl motors.

The eBay vendor is technically right in his description, it will "fit" and work on the models he listed, with exception of the tach. Not an issue for most folks since the OEM Merc tachs are getting quite rare or have died by now.

Note that these switchboxes all have the "2986" prefix, but the "A#" tells you exactly what motor it was intended for. For example, a 1975 850 used a 2986A22 box, while a '75 1500 used a 2986A25 box.

'70 800: 2986A8; '70 1350: 2986A4. All these numbers have been superseded by newer ones, but they still retain the core "2986" number.

So, any "2986" switchbox will probably work, with the above caveats.

Here's a shocker: the 1500 switchbox is NLA from Mercury but the last listed price was over $395! Aftermarket #'s for this box are Sierra 18-5779 or CDI Electronics 114-2986.

Here's a 6-cyl box for $60 or best offer: Used Mercury 332 2986A21 Switch Box | eBay

A little scruffy, but guaranteed to work.

There's a way to bench-test all these parts before you install them, once you've got 'em all gathered up, we can discuss.

BTW, a new rotor shaft (when last available) was over $462 and a distributor cap is almost $141 so I reckon that wasn't too bad a deal on the complete distributor, eh?

HTH........ed

 

[teletekman]

Re: 1973 Mercury 1500 I-6 with 65' or 66' Ignition Components?

Thanks for the info Ed! You are a true encyclopedia of information as well as the many other great minds on this site. I wen't ahead and ordered that switchbox from the link you sent me so hope everything works out. I will definately keep you posted when all the goodies come in.

Thanks again!

 

[teletekman]

Re: 1973 Mercury 1500 I-6 with 65' or 66' Ignition Components?

Ed,

Ok, everything came in last night finally. The switch box and distributor look as grimey as the pictures I got off fleabay so hopefully a good cleaning will do the trick.

I did note the inside of the distributor cap on this thing and it looks to be brand new, There is no buildup on the contacts so that appears to be a good sign. I did spin the rotor and it feels good. There is a little bit of oily residue on the 6 hole "chopper disc" so don't know it that is normal or not. There is a little bit of carbon on the rotor so I can clean that up gently with a wire brush. Over all the distributor seems to be in good shape.

The switchbox also appears to be in good shape just a bit dirty. I am going need to wire brush the contacts to remove some of the oxidation off the screw terminals though. The black body of the switch box feels a bit soft and spongy not hard like an epoxy style contruction I would think would be. Does this sound like anything to worry about?

The coil also looks to be almost brand new. A little bit of grime but I can easily clean that up. I would say in all I think I scored pretty well on what I paid for these. I'll take some pictures of everything tonight when I get home by the way. Sorry it was a little late when I popped everything open last night.

You were mentioning to me a way to bench test before I go installing everything. You mind educating me on that?

Thanks again,

Sean

 

[emckelvy]

Re: 1973 Mercury 1500 I-6 with 65' or 66' Ignition Components?

Sean, sounds like you got some good parts!

Here's how to get them tested:

First, we're going to test the coil and switchbox together. I'll explain why as I go.

On the ign coil you'll find 2 wires, black and green. On one side of the switchbox, you'll find green, brown, red, and white terminals. On that same side you'll also find a tapped hole next to the white terminal.

The coil black wire is screwed to the tapped hole in the switchbox. So now, the switchbox and coil are grounded to each other. The green wire on the ign coil connects to the switchbox, green terminal. This is the HV output from the CDI switchbox to the coil.

On the other side of the switchbox you'll find the 3 distributor connections. CAUTION: Never apply voltage to these terminals as it'll likely blow the box.

The dist. connections are black, white, brown and this corresponds to the colors of the distributor wiring.

However, we're not going to hook up the distributor yet, 'cause we first want to make sure we have Sparkies from a working switchbox/coil combo.

So, to do this test, you'll install a jumper wire between the brown and white terminals on the dist. side of the switchbox.

Install a chunk of spare plug wire or coil wire into the Merc coil. Note that it's different from the old-style coils in that there's a small clip soldered to the end of the coil wire, which helps keep the wire in place once it's slid into the coil. Use a strong light and you'll see that the coil wire has to go into the coil quite a way before it bottoms out.

I don't expect you've got the special Merc coil wire for this, but any old solid-core plug wire will work for this test. I'd suggest stripping out about 1/2" insulation off the end of the wire and bend it over, this'll contact the coil good enough for this test.

Take the free end of the plug/coil wire and position it about 3/8"-1/2" from the metal case of the switchbox. Somewhere far away from the terminals, 'cause you don't want the spark going there, it'd probably blow out the box!

Now you're set up and ready to apply power to the switchbox.

Both red terminal and white terminal need to have +12V connected to them. Connect the Neg (-) wire from your power source (can be a battery or battery charger) to the switchbox case.

Once you're powered-up, go to the distributor terminals on the other side of the case.

Ground the black terminal to the switchbox case and every time you do this you should get a spark out of the coil. If it doesn't spark, the switchbox is probably bad, but they're usually quite reliable and I expect it'll work. Coils are extremely reliable and I've never had to replace one.

You can ground the black terminal with a screwdriver, but it'd be 'cleaner' to connect a short length of wire to the black terminal and ground the wire to the case.

Once you've proven the switchbox and coil, now's time to test your distributor (and your luck!).

Remove power from the switchbox. Remove any/all jumper wires from the distributor connections at the other side of the switchbox.

Connect the brown, black, and white distributor trigger wires to their respective terminals on the switchbox. Connect the black ground wire from the distributor to a grounding point on the switchbox.

Apply power to the switchbox white and red terminals and spin the distributor drive shaft (doesn't matter which way, it'll spark either way!).

If it sparks like mad, you've got a winner!

If it doesn't spark with the distributor connected, and you get spark in the first test with the distributor bypassed, the dist. trigger is shot. But at least the dist. sounds like it's in good useable shape otherwise. As discussed, those other parts ain't cheap!

You'd have to dismantle the dist. and replace the entire trigger housing assy as we also previously discussed, but if it comes to that point, we can go into that in-depth.

Maybe you'll get lucky and have lots of sparking going on, cross your fingers!

Let us know how it turns out............ed

p.s. the oily dist. is normal, you've got a lot of gas/oil fumes going around in there. You can clean the cap out with carb cleaner, I'd recommend pulling out the carbon contact/spring in the middle and cleaning as well, they get pretty gunked up. The switchbox potting is a urethane or other type of plastic compound and isn't hard like epoxy. Sometimes it'll get softened even more from exposure to fuel/vapors/heat, but if it's working, not really an issue.

 

[teletekman]

Re: 1973 Mercury 1500 I-6 with 65' or 66' Ignition Components?

Cool, thanks Ed! I'm working on setting up my test bed right now. I'll keep you posted.

I forgot to ask one thing. There is a mercury switch that ties into the brown wire/lug on the switchbox coming off the distributor according to the wiring diagram for the 1500. Is that needed? What exactly is that for?

I just realized I never ordered one of those...

Sean

 

[emckelvy]

Re: 1973 Mercury 1500 I-6 with 65' or 66' Ignition Components?

That switch is actually filled with the metal mercury and acts as a kill switch if the motor should hit an obstruction and flip up out of the water. The switch is mounted on an angle and just like a furnace thermostat, when tilted the mercury runs into a pair of metal electrodes and completes the circuit.

In this case, the circuit is completed to ground, which kills the ign. If I recall, the switch is connected to the brown terminal on the dist. side, but you don't need one to make sparks for testing purposes.

When you've completed the first test, just connect the dist trigger wires as per color code, connect dist. ground wire, and she's ready for spark check..........ed

p.s. the number for the coil wire is 3836A1, which is superseded to 821945A5 for $12.51.

Here's an original part on eBay:

Distributor to Coil Wire for Mercury Outboard Motor 393 3836A1 New | eBay

 

[teletekman]

Re: 1973 Mercury 1500 I-6 with 65' or 66' Ignition Components?

Well good news all around! Ran both test's as you stated and both passed with flying colors so it looks like we have a winning combination! She's sparking like a bat out of hell!

We are going to start wiring her up tommorow so I'll keep you posted.

Thanks a million Ed!!! :thumb: :thumb: :thumb:


Sean

 

[emckelvy]

Re: 1973 Mercury 1500 I-6 with 65' or 66' Ignition Components?

Once you've got the parts installed, you're gonna want to do this link-n-sync procedure to ensure everything is set up properly:

http://forums.iboats.com/engine-fre...q/timing-sync-merc-inlines-1988-a-168855.html

Here's the Long Version, with tons of questions that you may find useful:

http://forums.iboats.com/mercury-mariner-outboards/timing-sync-merc-inlines-1988-a-128495.html

Glad the stuff worked out, you got an excellent deal on a working, Inline CDI distributor!

 

[teletekman]

Re: 1973 Mercury 1500 I-6 with 65' or 66' Ignition Components?

Ed,

Sorry I havent updated you on this yet. We are still working on getting everything installed. Extra time has not been my friend lately.

I was looking at this rectifier that is currently on this block and noticed it too looked a bit rugged. I tested it out and sure enough one of the yellow terminals is bad going to the stator. I failed to check this before while ordering my parts originally, so I looked up on ********** and a couple of other places and noticed that they list a part number of 332-2910 for the OEM replacement. However the part I have now is a 332-4252. The parts look identical looking at pictures of them but do you know what the difference is?

Thanks,

Sean