TOPIC: Points to Petronix Ignitor system converstion

Painting of the '63 1000 is progressing in between all the other commitments of life. Soon I'll re reassembling and suspect I'll need help with that. Took notes, took pictures, but you know there will be a few of those “Um……I don’t get it” moments. Or the “uh oh…what’s this”. Etc.

But in the meantime, I've started pondering a electronic solution to the twin point ignition set up which I suck at setting up. Rather than sourcing out all the components of the compatible vintage set ups , I'm going to attempt to set up a Petronix Ignitor solution. That is, the conversion kits made for specific automotive distributors.

I've sourced a spare distributor 'pan' (the section with the points inside onto which the rotor sets) to use as a test bed (thanks Doc!). The goal is to devise a way to mount the magnet ring and the ignitor module in the distrib pan. I'll use one ignitor for a six cylinder motor, so I’d be converting over to a single vs. dual system.

I'll likely have to cut a hole in the top of the distributor pan so the ignitor can fit in and would protrude up into the cap. I suspect I’ll have to rearrange the wires on the cap so as to have the correct firing order . I'd isolate (but not remove) the circuits for the other half of the original system so as to not have any leaks or shorts.

I'll use the ignitor II (vs the orig ignitor module) which detects RPMs and adjusts to maintain a constant dwell (vs the elongating dwell experienced at high RPMS for a standard set up points).
I don’t think I'll have to worry about or do anything to the mechanical advance that occurs in the first part of the throttle advance (the rotating of the distributor) or anything with the throttle links, stops, idele adjusts or any of that.

So, assuming I can craft a way to mount in the magnet ring and the ignitor, what am I not thinking about? Not sure what dwell I need to find ( do all or most 6-cycl single ignition systems use the same dwell? )

Hi Peter,
Great idea, I've been contempating this as well.
The orientation of the sensor and the rotor pick-up will need to fire number on number one cyl close to where the points trigger for number one cyl otherwise the distributor will not be in the right rotation for all the linkage to work. The stumbling block I saw was fitting the pick-up and magnetic rotor within the space allowed becasue of the Merc rotor design (lower flange) on these motors.
I was contemplating a whole new plate being machined rather than adapting an old one but the more people looking into this the better.
You will now need timing marks on the flywheel with a pointer on the bock some where.
The flywheel on the 1000 has a nice flat circumference to put a timing decal on. If the dia is the same as a later model then you could use one of those. In any event if you have to make a decal then it's a matter of converting degrees into distance to make the decal.
Measure the circumference of the dia the decal would wrap on and simply divide by 360 which would give the distance between each hash mark on the decal that would mark a degree. Find TDC per usual measuring with a dial indicator in the plug hole set up a permanent pointer on the block and place the decal with TDC on the decal lining up with the pointer with piston #1 at TDC. The last thing is to know how much advance you need in degrees as the old motors are listed as a piston distance before TDC. So using the same indicator in the plug hole rotate the motor to that piston position and see what degree mark the pointer is pointing to, that is your timing for WOT. You would WOT time using number one cylto that degree mark.
Do the same for the carb pick-up position although this is usually 4 to 6 degrees BTDC.
I'm sure there are still more details to be thought out.
Randy

Thanks Randy! I appreciate the help! I plan to conquer this one.

So I get that I'd have to position the Ignitor to fire on the same timing cylinder as the #1 set of points, which in the case of a '63 1000 is #3 cylinder. Hadn't thought of that.

Not following why I would need to move the timing to #1 cylinder, which was the standard for the later 6's. These Ignitors function in the very same manner as a set of standard points. So not following why the timing change. Help me out on that.

Have you thought about the coils? And why you have two

I hve successfully converted the dual point disto on my (GASP!!!!)
Evinrude Starflite. The engine starts instantly, idles slowly ans smoothly, doesn't load up, and can go like a raped ape.

Let me share my thoughts on modding the Mercury - because I've spent considerable time pondering it - armed with the knowledge from the Evinrude conversion.

Abandon the side tap for the No. 2 coil. The firing order - sparkplug wire order does not change. The 2 coils simply worked in tandem to give more time (dwell) for each coil to charge. Since they both discharged out the top of the rotor (like a conventional disto) Nothing needs to change. Am I right or wrong - here Doc?

As for the ignitor - it needs to be located as close to the magnet array as possible. I used a piece of paper to set the gap on my Evinrude. This distance sets the dwell of the module. Set it too far away from the rotor & operation becomes unreliable. If you can, use the provided magnet array. You need to get one for a 6 cylinder car engine. The magnet array must have 6 magnets. The engine will fire correctly, because the crankshaft & disto are on a 1:1 link. A four cycle engine spins the disto at 1/2 the speed of the crank. On my Evinrude, I used a lathe to turn down the distributor cam lobes until the magnet array would slip snuggly ofer it. I had to use a 3/4" socket and a small ball peen hammer to put it fulll in place. Since the magnet arrays are molded to slip over distributor cams - they have high & low spots molded into them. However, the are enough "high" areas inside the array, that it will fit nicely on a perfectly round shaft. We used calipers on the array to find the true diameter, then we cut the disto cam down & used a micrometer to get the correct size. It worked great.

I believe the best approach on a mercury is to cut down the cam lobes down to the point where a new collar sleeve can be slipped over it & tapped into position. This collar would then be turned down to the correct diameter to accept the magnet array. The metal collar would need a drop of locktite between it & the disto shaft. It will never be distrubed again. The use of a factory magnet array keeps the proper triggering and allow replacement if something goes "wrong" with it.

If the lower ring on the rotor is in the way, use a lathe to cut it off. It isn't needed. If the o ring on the disto shaft is in good shapt, there should be no need to locktite the rotor on the shaft, anyway.

Take a stock distributor that is properly synchronized and adjusted. Put the number 1 crankpin at top dead center. Mark the pully of the disto body with a sharpie and put a mark on the disto pully that lines up perfectly with it. Remove the disto from the engine. You now need to install the modified shaft into the disto body. With the pully and disto marks proper aligned, install the magnet array with one of the 6 magnets directly in front of the module. This would mean that the Hall-Effect transistor in the module is in the fire mode. Double & tripple check that this is correct. The magnet arry shoult fit snug on the modified shaft, but can be gently pried off with 2 flat blade screwdrivers. Do it 'till it's right. Re install the disto & check the timing. Any slight changes from specification can easily be adjusted.
When I dropped the disto on my Evinrude , the timing was perfect. I haven't touched it since.

I suggest you also install a pertronix hi power coil as well.

THIS IS WHAT IS SO COOL ABOUT THIS SITE!
I do have another thought and that is the coil will be discharging far more frequently in this situation. There may be a an issue at higher RPM's due to this, but I don't know. I believe one of the reasons Merc may have used two sets of points and coils was to have each system firing what would be equivalent to a 4 stroke 6 cyl which would provide longer point life and possibly allow enough time for the primary coil windings to charge and collapse even at WOT.
A single coil on a 6 two cycle at 5500 RPM would be putting the same demand as a 6 cly 4 stroke turning 11,000 RPM. Merc used different coils once they went to the single coil, granted this was also because of the thunderbolt ignition but I'll bet the coils were also constructed in a way to speed the charge and collapse of the primary windings. You may need to swap to a different coil.
Just thinking about potential issues, don't know if it's real or not.
Randy

Randy - that is a very good point. However, the Hall Effect transistor works differently enough that one good coil can easily do the job. The Hall Effect transistor only breaks the voltage to the coil for a fraction of a second - enough to cause the coil to dump HV to the plug. This happens when a magnet aligns with the center of the module. As soon as the coil charge collapses it is instantly recharged. More than enough time to fire the next cylinder. In the case of a breaker point on a merc, the crank has to turn roughly 60 degrees to cycle each point set. The closing and opening takes a lot of time because of the cam profile.

The Pertronix ignitor also boosts the voltage going to the primary winding of the coil. I believe the module is able to produce a healthy spark up to 20,000 rpm with only a couple degrees variance.

For fun, I chucked up a bolt in my Milwaukee power drill and slid a 4 magnet array on the bolt. I hooked the ignitor module up to a crappy old coil, and a 12 volt battery. I hooked the coil HT to a nail aimed at my bench vise 2 inches away. Turned on the drill and held the spinning magnet ring in front of the module. Good God - it was like a blue/white blowtorch leaping off the end of the nail, no matter how fast the drill went.

A bit of caution - if you mess around with one of these - be VERY careful. Also, only hook it up to a 12 volt battery - NOT a battery charger. Be sure to always have the polarity correct - they are expensive to replace.

Well, thats Cool, you all went with my very short question (as I hate typing) and gave what seems like good answers.

"(I suggest you also install a pertronix hi power coil as well)", if this and the "Hall-Effect transistor"? in the module will maintain good spark at 6000rpm continuously that answers my doubts. I just thought before hearing these answers above that the motor might might misfire/stumble at peak RPM's from lake of coil saturation.

EXCELLENT! Thanks guys for the feedback - really looking forward to setting this up. I feel much more confident that I can pull it off. I also suspect I'll see a noticeable boost in fuel efficiency. With this upgrade and the circa '85 PTT I've retrofitted she should be a handy motor!

Boy, I don't know about improved fuel efficincy - but who knows. I didn't get the chance to use my Reinell enough after the mod to tell if it improved the thirsty V4. I had to retire the boat to replace the transom. I can tell you what it will improve - it will start easier, idle better, and it may run more smoothly. What it WILL do is to keep you from having to spend a mint on those inline point sets. I haven't bought any in a few years, but last time I did - oh boy did it hurt. Something like 35 bucks per side......

As a post thought - I opened up the gap on the sparkplugs to .045"

Have any of you thought of using the Crane XRI it uses the points cam directly. This way you do not have to mess around with fitting the ring over the cam like you do with the Pertronix. I have used the Crane system on my 68 Ranchero 390 up to 6500 RPM with no issues. The Rev limiter may be a problem though.
www.summitracing.com/parts/CRN-750-1710/

Peter, this has turned into a great thread. Kinda like having a HUGE Research and Development team behind you, right!? Many of us are hoping you get this figured out, you can tell by the responses you're getting. As Bruce said, those points are getting crazy high in price (They're even higher now, by the way!). The question of this concept had occurred to me before (probably many of us, really), but was discarded as "un-dueable". Kudo's to you for taking it closer to reality. Good luck man, we're pulling for you.

I have been following this tread with great interest. I also have been trying to figure out a way to do this. I guess I can quit scratching my head now. I just have one question left, does anyone think that this would be doable on a Merc 700 dockbuster? I would like to use this idea on it if possible. Thanks Skip.

All of the timing changes required when going from forward to reverse in a Direct Reversing motor happen in the distributor drive assembly. So, any successful dual-points electronic ign conversion should work regardless of whether it's a Full Gear Shift motor or a Dockbuster.

Here's the page from Crane Cams with ign info, you can access .pdf files for 2 different types of ign, the XR-i setup and also an optical trigger:

www.cranecams.com/view.php?s_id=17

The XR-i is self-contained but the optical trigger requires a separate CDI-type ign module.

I'd suggest that a module such as the old Mopar units used with points ign would work well with the optical trigger. And they're fairly inexpensive. If you happened to have a Merc "SS" style points-triggered CDI switchbox kicking around, it would work as well.

A few thoughts on the XR-i setup, it's gonna be sensing off a 3-lobe cam, wouldn't you need a 6-lobe to provide the proper signals for a 6-cyl motor? After all, the original setup uses 2 sets of points, each running 3 cylinders.

And later model Merc CDI ign's run a 6-hole chopper with a single pickup.

The optical-fired system is available with a 6-slot plastic chopper and the only issue (aside from mounting the pickup) you'd have is the fitment on the Merc points cam (same issue you'd have with the Pertronix cam I reckon).

Here's a link to the Summit page with info on the optical ign:

www.summitracing.com/parts/CRN-700-0020/

Here's a silly silly thought, 100hp and 1250 Mercs with full-CDI ign have a distributor head that mounts with 4 bolts just like the dual-points distributor. So, why couldn't you just take one of those units and bolt right up to a dual-points distributor drive unit, use a "normal" Merc switchbox and coil, and away you go!

See these eBay auctions for examples of what I'm referring to:

cgi.ebay.com/ebaymotors/100-HP-MERCURY-OUTBOARD-DISTRIBUTOR-1967-MODEL-/370547242581

cgi.ebay.com/ebaymotors/Mercury-1250-complete-distributor-and-spark-plug-wires-/260865752211

Note that some 60's models of the 650-4 used a similar-style ign but of course you'd have to change out the chopper disk to a 6-hole vice 4-hole. The one advantage this ign has over the newer ones is that the trigger module is replaceable. Not that it's cheap!

Cost-wise, all the old Merc CDI ign's are really expensive unless you can find a good deal on Craigslist for a parts motor with functioning ign. If you can work out a good mod using one of the aftermarket triggers, whether it's optical or magnetic, it should be a very inexpensive way to get away from points.

The good Dr. FrankenMerc did a nice job converting an older dual-points ign motor to full Merc electronics but not all of us have as many spare parts kicking around!

Just brainstormin', HTH.........ed

The good Dr. FrankenMerc did a nice job converting an older dual-points ign motor to full Merc electronics but not all of us have as many spare parts kicking around!

I remember that thread/post Ed, it turned out really NICE! (OF course it did, Thom did it. LOL) As you stated, the problem there is rounding up the Merc parts to do it. Good input and links though, my friend. Thanks

I'm thinking to use a points replacement on my Mk78 one day. Thing is if the XR-i fits in the distributor you'd need 2 not one as stated below if the cam has 3 lobes for duel points. If the module will fit/adapt and you want to pay for two, seems like this would be a very a simple installation unless i'm missing something, and yes, probably am. If i'm in the ballpark the original coils would remain as would all the timing except dwell I guess? The 8000 RPM maximum limitter in the XR-i would not be an issue with a 3 lobe cam unless you plan on going over 10,666rpm,lol. All the applications I saw were for V8's for the XR-i but one module could possibly be similar to replace the Merc points? Any thoughts? Besides spending double for two units but you'd probably save on a new coil and machining....

Thanks guys for all the input!
I like the idea of the Crane. Yes you would need two, set in such that the synchronization between the two is correct. And I like the idea of the rev limiter. Set it at 5K and not have to worry about spinning the motor out if the prop leaves the water or breaks lose.

Looking at the pics on the summit site, the module looks fairly large, so wondering if it would even fit in the distrib pan. With two, would I be able to position them to achieve the synco positioning?

Also looked at the Petronix Ignitor III which can use the cam lobs or a mag ring. It looks even bigger than the Crane, so cant see two fitting two in if using the cam lobs, and if you were to use the mag ring, then I'd go with the Ignitor II which is smaller.

Great to have options!

(ps if I pull this off, I'll be selling off two sets of NOS points to offset the cost. Sweet)

OK so a few more thoughts on alternatives.
As stated, the first year thunderbolt used points as the trigger.
The points don't pitted as the current is so low that the contact faces will last for a long long time. Granted there may be some cam/rubbing block wear over time but, it is really the contact surfaces degrading that prompts service. As the cam /block wear over the years , just re-time the motor. We'll be in wheelchairs by the time it's so bad that the points will need re-adjusting. If you started with fresh cleaned or new points and set them up as needed for a 66 Merc 6 cyl. you could use ANY Merc switchbox for an inline 4 or 6. Finding a single lug Switchbox on the dist side is rare so, for a newer one, on the three lug side of the switchbox jump the top two teminals together and then put both of your points wires onto the bottom black lug. This performs the same and is what Merc instructs to do for the earlier points triggered thunderbolt as the Switchboxes all superceed to a new number having the three terminals.
Now you need the thunderbolt coil, I think the best choice packaging wise is to use the smaller later year 75 up 6 cyl coil that bolts to the block under the dist. The Left lug on the coil goes to ground and the Ferrite surrounding the coil also needs ground, use the aluminum cast hiousing that these coils are typically held with would be best. Bolt it to a plate and ground the plate when mounting it somewhere.
On the 4 lug side of the Switchbox the wiring is straight forward.
The Red teminal gets full time 12 volts, pull that from your started solenoid. the white is switched 12 volts , pull that from you existing switche 12 that goes to your resistor train for the coils. the green lug needs a jumper to your coil. the tan is a tach drive for the earlier tachs. Otherwise, if your stator is a 12 pole then tap tht for a later tach drive.
The switchbox also needs to be mounted, I think it would fit on the resistor side of the block seeing all that has been removed and the new coil can go where the old coils have been removed. SO there is room to package a switch box and the coil.
I'll bet an alternative is to use the whole set up from ADI.It's very compact, you could still trigger with the points.
This set up should not need service for YEARS. You can time the motor as per instructions for your year as you can still go off the points break to static time. Or with some marks you can do running timing with a light, as descrided before.
This would seem to be best compromise with minimum fuss.
If you want the ultimate then you can add as mentioned a distributor from a later 67 to about 69 Merc which would fit and eliminate the points. Your wiring will have to change, another hassle.
I'll also wager that the CDI system, it's compact for a Merc 6 would be another way to go, this could be points triggered. It has the switchbox and coil all bolted onto a plate already. You would need to use the stator as a tach drive though. This may be easier and probably not much more $$ New than hunting down the Merc stuff used.
My two cents,
Randy

And so begins my attempt to convert my '63 1000 dual point system to a single electronic system using a Pertronix Points Conversion kit. Since there was such good input on this thread I decided to continue this one vs. start a new one. Please forgive the length of this post…

As most of you probably know, or at least as I understand them, the “typical” points conversion kit uses a plastic ring which has magnets set in it and a ‘pick up’ module. The mag ring is designed to slip over the cam lobes of the distributor for which it is designed. The module is mounted to a plate that is designed to mount in the distributor using the stock mounting points for the points. As a magnet passes the module’s pick up it triggers the module to open the primary circuit (the same as if a set of points was opening). So different kits have different mag rings and different module mounting plates depending on the distributor. Another type of kit uses a module that has some sort of optical pick up triggered by the cam lobe passing by, so no magnet ring, but are otherwise the same approach

But of course, none of these kits are set up for a vintage mercury outboard. But why would that stop us?

Petronix makes a few kits; Ignitor, Ignitor II, or Ignitor III, with each having more features than the last. The Ignitor III has an adjustable RPM limiter, which I thought ideal for a boat motor to protect it from over revving when the prop cuts loose for whatever reason.

I stayed with mag ring approach over the optical pickups (ex:. the XRi). There are only three cam lobes on the distributor shaft and I don’t want to have to use two modules (and synchronize them) and I don’t think those larger units would fit anyway. I opted out of a stock Mercury Thunderbolt conversion as I don’t want to source all the used parts, learn it, and set it all up, hope the parts are good, etc.

So I went with a Pertronix Ignitor II. I was not able to use the Ignitor III with the RPM limiter as I had hoped because it is not a sealed unit and the Pertronix tech guy said they not do well in marine environments. The Ignitor II has adaptive dwell (maintains dwell throughout the RPM range), adjusts spark timing through the RPM range (improves high RPM performance), and senses start up & increases energy for easier starts. So that's cool...

The tech guy was able to give me approximate dimensions of the PII module. I mocked up a little wooden block to simulate the module, and it appeared that I can fit it into the distributor "pancake" (the metal Primary housing where the points are mounted, and the plastic adapter plate the distributor cap fits to). I will have to cut a hole in the adapter plate as the module is a bit too tall, but appears will clear the lower ring of the rotor (if it doesn’t I’ll just cut the lower ring off).

I measured the diameter of the distributor shaft (.5 inch) and called the Pertronix Tech guy back. He searched through the six cylinder kits to find one with a mag ring designed for a shaft diameter of .5” or greater. None of the kits were .5’s (as we expected), so went with a kit that is slightly larger so I can devise an adapter ring. Key to note is that unlike automotive distributors, the cam lobes on the Merc distrib shaft are cut into the shaft, vs. standing proud of it, so I can’t turn the shaft down to match the mag ring.

As noted above, the mag ring has an interior shape that fits over the lobes of the distributor cam. For a six cylinder distributor this means the ring will have a hex shape inside. My approach is to find a bolt that fits snuggly inside (a 17 mm bolt fits perfect) and then drill out the bolt to a .5” inside diameter so that is slides over the distributor shaft. The critical part here is to have that bolt drilled out dead center. If it is off center, the mag ring will wobble, resulting in uneven magnetic pulses on the module and wear on the distributor shaft bearing.

I’ll also have to devise a way to ensure that the ring/bolt assembly does not move on the shaft. If it moves it will spoil the timing. Probably just lock-tite? I’ll also have to remove the pin and o-ring from the shaft that positions the rotor, without damaging them, in order to slide the ring/bolt over the shaft (then reinstall).

Next will be to create a flat bottom on the primary housing by grinding off the mounting points for the points and condensers. I can then mount the module plate. All I need to do is ensure the gap between the ring and the module is correct. I don’t need to have the module plate perfectly centered on the shaft, but will get it as close a possible while maintaining that gap.

Here are some Pictures. Once I get this worked out, I’ll move on to timing. Note this distributor is a spare, not my running distrib…..

The Kit: 9LU-163



The mag ring (upside down)– note the hex shape inside



Mag ring (again upside down) with Bolt inserted.



The distributor shaft – note that the lobes are cut into the shaft, and that the very tip of the lobes are flush with the max diameter of the shaft.



The module and mounting plate. Looks like I will be able to orient it anyway I need to once all the mounts are ground off. Should be easy to mount (just jinxed myself)

Progress from last night.

My neato beato stand I use when setting points. The distributor pan sits in the hole then I simply screw the pan to the board. An engineering marvel.



Here is the pan before.


Now after all the mounts are ground off. Using a grinding wheel in my power drill I ground off the condenser and points mounting point. I used a Dremel with a cut off wheel to remove the post for the points and then the grinding wheel to finish it off. Then the Dremel with a sanding disk to sweeten it all up (and clean off the remnants of the gasket).


The Ignitor and mag wheel set in place (no bolt in the mag wheel yet). Note the mounting pin for the rotor is removed. I didn't have punch of any kind that was the right thickness or long enough to push the pin through. So I took a finish nail and using the Dremel with a sanding disk ground the head down to just under the diameter of the pin and GENTLY tapped it right trough. Need to make sure the nail is less in diameter of the hole so you can pull the nail back out.



Next a dry fit of the Rotor to check clearance. Not much thought here yet, just wanted to see what the challenges might be, but you can see I'll need to modify the rotor.



That's all for now.....

Very interesting project Peter!!
And remember,...I have O'Plenty of those old school dual point pancakes if you need any extra goodies to experiment with.
Thom

Peter - you're off to a good start. Please allow me to make some important observations -

The magnet collar is very low in respect to the ignitor module. It is best to keep the centerline between the two paralell, or as close to paralell as possible. Remove the ignitor module from the dwell plate and mount it directly to the disto housing. That will lower the module at least .040" Just drill the rivets out and remove the module. When you find the best location, mark the mounting holes with a sharpie, drill & tap them. I believe that I used 6-32 screws on the 'Rude.

I'm confident that the disto shaft needs to be modified to make this work correctly. I encourage tou to remove the shaft and bearings from the housing. Remove the bearings from the shaft. Put the shaft in a lathe and braze or wire weld the existing cam lobes over. This area will need to be built up and then machined down to be perfectly round. I would shoot for a finished diameter that is perhaps .060" larger than the rotor shaft. It will end up looking like a collar. Who ever welds it will need to be very skilled in heat control. The weld does not have to be pretty - as it will just serve as a "spacer" of sorts. When the area is adequately built up, turn it in the lathe to flatten the face and square up the edges. This will be a delicate operation, cut just a very slight amount off at a time. The shaft and built up area must be kept true with no wobble. When this is done, you will need to fabricate an adapter ring that will then be tightly pressed over the newly created diameter of the shaft. Use a drop of locktite when the two are pressed together. Then, finally, turn down the outer face of the adapter ring untill the magnet ring fits it snugly. This is not as hard as it sounds. Just a bit more work than you may have anticipated. I can tell you, that this will net the best results.

Have FUN!

Bruce

Thanks Thom, I haven't forgotten your bucket of parts. I was thinking just that as I started to grind on the prototype pan pictured.

Bruce, you are correct about the location of the magnets to the sensor on the Ignitor Module. The Magnets are at the bottom of the ring and maybe 3/16 in height, and actually would not be passing in front of the sensor at all. Also, with the magnets at the bottom of the ring, it wants to stick to the bottom of the pan. And last, the mag ring diameter is much greater than the bearings and so I was needing a way to raise the ring off the floor of the pan, but couldn't afford for the ring to be higher as the rotor wont have room to mount.

Standing there at 11:00 pm staring at it, it occurred to me. Flip the mag ring over. Now the magnets are right in front of the sensor, the mag ring isn't attracted to the bottom of the pan, and!!! I can now sit an o-ring on the bearing to lift the mag ring just off the pan. Presto! Sometimes you just get lucky

Here is a pic of the Mag ring flipped, with O-Ring underneath (ignore the o-ring sticking up - it's just shoved in there to position ring for the photo)



As for your thoughts on the Distrib shaft. I may need to go there if my plan doesn't work out, which is to make an adapter ring out of a a stainless steel hex bolt. A 17 mm bolt fits snug in the ring. I'll drill out the bolt to the size of the shaft, which is .5 inches, and it will slide on (more on timing implications later)

I'll draw up an illustration tomorrow and post for feedback

The bolt/ring combo (not yet drilled to shaft size. )

Well boys and girls, after a week of regular life I got into the shop to experiment a little and have determined that Plan A won't work.

The Lobe area of the shaft is actually ever ever so slightly less in diameter than the top, round part of the shaft. I took a washer that has a .5 inch center hole and slide it onto the shaft just as I would a drilled out bolt. It was snug going over the top round section, but with the triangular shape of the lope area and the slight different in diameter, it moves all around on the cam lobes.

So more pondering in the dead of night as I consider a few approaches; a sleeve, building up and turning down the shaft as described above, etc. I have a Shop Smith with a lathe, and just may be setting that up (for the first time ever)

I shall not be thwarted!!

Well, havent had much time to look at this project guys, but havent bailed on it at all. I've run a few "experiments" on building out the distributor shaft to accept a mounting bolt for the mag ring, but with no success. Note that total time spents is like, 2 hours, over the last 6 weeks.

Hoping to get some pics up this weekend.....

Pete

Alrighty then. So having conceded that I'll need to build up the distrib shaft to a diameter that will fit the Mag ring, I tried a few things with epoxy with a form fitting over the distrib shaft (actually a mock up of the actual shaft) But even with trying to seal the form at the bottom, the epoxy is too fluid and runs out.

To make experimentation easier, I decided to try and extract the shaft/bearing assembly from the pan. With some guidance from Thom and Ed it was actually quite easy.

I used a socket that just fit over the shaft so as to stay on the shaft itself. Then two blocks of wood on either side of the pan to give the shaft room to move out. Put the whole thing in the vice, and pressed out the shaft and bearing. With these components out it will be much easier to modify the shaft and true it up simply by chucking it in my lathe (or a power drill really)

To press it back in, I'll reverse the process using a deep socket.

The "Press Assembly". This is to give you an idea of what i did. What you see here is my distrib pancake that still has the full points set up (was oh so ginger with it). When I did the prototype pancake it was flush against the blocks


The Bearing/shaft assembly out


A closer look


The socket over top the shaft, which served as the press ring


Onward!

Some promising results on a recent test using epoxy putty to build up the distributor shaft to take the Pertronix Mag Ring.

I cut the head off a small carriage bolt, then filed the sides down slightly to provide a similar profile to the distributor shaft. Then packed epoxy putty around the carriage bolt (making sure to stay off the threads). Let it set completely.

Next, chucked the bolt into my shopsmith and using the lathe attachment, spun it down round, centered, smooth, and to the diameter of the Mag ring. The epoxy is easy to work with standard lathe tools.

Next, chucked the piece into a high speed drill. At max speed the "shaft" stayed perfectly centered. No wobble. Then bashed it on the bench over and over. Didn't break or come off. Then using simple tools, removed the epoxy.

What I think I have is a material that will stay put, wont be affected by moisture or the level of heat in the engine, easy to work, adheres to metal completely, and if I don't get it right the first time, can remove and try again.

More to come as I try it for the first time on the distrib (which I will clean thoroughly to ensure there is no grease to affect thee adherence)





Oh, and a picture of the Rude I bought last night for 40 bucks. Tried to sneak it into the house and was instantly busted by my daughter. Idle threats were exchanged, a struck a deal regarding Starbucks, and now think I am safe from the wife spotting it

Hi, New guy here. I have been contemplating this feat myself and caught this thread on a web search. I have a mark 78 that I want to convert. I have also visited the afore mentioned Pertronix and another site Hot-spark. They both also make a 3 cylinder module kit. I'm thinking that I could use 2 of these and still use both coils and the original dist. shaft with the 3 lobes.
I think I had registered here a long time ago when I had a 72 Glastron 156 but just created this I.D. to get on here and comment. I now own an early Checkmate that I'll be puttin this Mark 78 on. I am a active Member on John's old Merc site but will be posting more here also.

Unfortunatley I've been so busy at work and home that I've not touched any of my merc projects but a few times in months.

I have the distributor shaft ready to chuck in the lathe to create the "lobe" for the mag ring. I'll post a pic later today - for now it's off to a friends sail boat for the day.....

So here is the replacement distributor ready for the lathe. I used an expoxy putty to build it up (remember that on this shaft the lobes are cut into the shaft, not proud of it as on a typical distributor). It cures rock solid, adheres tenetiously, and is water proof. I'll chuck the shaft into the lathe and cut the epoxy down perfectly round and to a diameter so that the mag wheel fits snug. The blue card comes off before turning and was used to keep the expoxy out of the bearings.

I'll post with the results....

I'm dying to see how this works out in the lathe.

I really hate people who are this clever. They make me feel inadequate....No just plain DUMB.

Hehe - we'll see how clever I feel when the old girl explodes in my basement! (wouldnt be the first time I had to fire off the ....fire....extinquisher in the shop)

Well boys (and girls), apologies that this has been such a slow thread, but life has a way of dictating what we have to do, vs. what we want to do (plus I kinda had to put the entire motor back together before really needing to worry about ignition).



Worked a bit on the distributor shaft. Recall I am using an epoxy putty to build up the distrib shaft to take the Mag Ring. Here's where I started. The cardboard twix the putty and the bearings rings was to ensure a gap so the spinning epoxy shaft doesn't contact the stationary bearings. It's two parts so that once the epoxy was hardened I could pull them out.





Chucked it into my circa 1960 shop smith, set up as a lathe. Note that this is my first time using a lathe, so I've been going at it really slow and carefully.



I spun it down to round.



One thing that I was concerned about is that the entire unit is spinning, vs just the shaft (that is, in operation the bearings are stationary). Was concerned that might introduce a wobble in the finished product. So I placed a clamp on the bearings. As the lathe spins the clamp holds the bearings stationary.



I worked it down to close to the mag ring, but was getting tired so called it a night (Friday night). Today hoping to fine tune it to where the Mag ring fits snug on the Epoxy shaft.

Thanks for the update. I love the ShopSmith.

Hit a road block on the conversion, but am working on a plan...

There is a white dot on the Ignitor that I assume (and there is the operative word) that the magnets should pass in front off. There is not enough room to get the parts in such that the dot and the magnets align without preventing the rotor from seating properly.

The work around I have in mind, assuming I have to get the Ignitor dot and the magnets to line up (the magnets are at the very bottom of the ring) is to mount the ring and the Ignitor Upside down. The Ignitor would be mounted to the plastic adapter. I'd takes some pics for illustration, but don't want to cut up the adapter just yet.

Going to call the Pertronix tech guys tomorrow and find out about the alignment.

In the meantime, two questions;

Has any one ever tried to pull the bearings off the dist shaft? I am afraid to try for damaging them, thinking Merc didn't intend for them to be pulled off once put on. I May need to in order to mount the ring upside down (has to do with the interior design of the ring)



Second (and I'll post this separately), I lost a lot of documents in a computer crash, including my copy of the timing wheel that one would use for setting and syncing a standard points. Anyone have one you can send me? e-mail in my profile.

Yes, the bearings will press out with little pressure. Just a vice and a deep well socket will work easily.
You can view and print out the timing wheel here...
johnsoldmercurysite.com/whitepapers/6cyldwellplate.pdf

Thank you!

Anyone care to share your techique to setting the dwell/sync? I tend to struggle getting the dwell right. I'll be just far enough off that I need to narrow it in, but then manage to make it worse (going to far in the opther duirection). How do you nnarrow in on the dwellwithout bouncing all over the place

Progress!

Called the Pertonix guys today and got some good help. He was able to confirm that the kit I have (9LU-163) has the magnets at the bottom of the ring, and that the pick up sensor is at the bottom of the Ignitor. So I need to line up the bottom of the ring with the bottom of the Ignitor, which they are already very close to lining up.

So I was able to finish turning the epoxy sleeve to fit. Note there is a two step shape to fit the interior of the ring. Here the sleeve is sitting snug on the shaft. I got the height just right such that the rotor fits properly and snug to the Mag ring. Spun the shaft and rotor and no wobble (at least visually).

I haven't yet turned down the rotor so the Ignitor will fit under it, nor cut the plastic adapter plate to make room for the Ignitor to protrude through.







A few other notes: The Flamethrower coil is matched to and optimized for the ignitor, so the advice was to remove the stock resistors. I'll jump them.

I must use suppression plug wires. Not sure if the ones I have, which I bought new from 'oldmercs.com' a few years ago are or are not. How do I tell?

Good work! I'm assuming the wires you bought, were for that motor and they are tinned copper core and have the screw in copper tips attached and are not supression wires. Supression wires are usually used to reduce radio interference. Ignition wires, that are supression, will usually say "supression" on them.