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I'm going through one of my two dizzies, and taking pictures along the way. This will help remind how it goes back together, and perhaps entertain some of you. I am converting both to the Pertonix MR-181A Hall effect system, assuming they work as planned.

On the Montreal webpage it says that the 6003-2RS is the ball bearing. This is true for the bearing at the base of the of the drive assembly mounted on the rear of the cylinder head and corresponds to the Alfa # 105.64.05.017.00.

The distributor itself, however, has two bearings. Neither has a part number stamped into it.

The big bearing in the bottom of the distributor is 15 X 35 X 14 (ID X OD X Height). This corresponds to a 2202, which can be had in a double-sealed version from McMaster-Carr for the tidy sum of $130.87. Yikes.

It is described as a Self-Aligning High-Capacity Steel Ball Bearings—ABEC-1
Open - Double Sealed "A sphere-shaped raceway and two rows of balls give these bearings a high load capacity and the ability to compensate for shaft misalignment."

I'm going to pry open the seals on my dead bearing to confirm it is a double-row bearing, but that seems a bit of an overkill for this application. The one from this first distributor is definitely dead, however.

The bearing in the upper plate is a 10 X 26 X 12. I can find no bearing with these dimensions. Although it might be replaced by a #6000 double sealed bearing, these are 8mm thick, not 10. It, like the bottom bearing, are held in place by riveted plates, so the thickness is important lest things wander up and down. It might be possible to use shims to hold the top bearing in place, however. I suspect it is also a high capacity double-row bearing. Anyone have a lead on these pieces?

More later as it all unfolds.
 

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Discussion Starter #2
Bearing update

I've determined that a 62202 2RS1 matches the dimensions of 15 X 35 X 14 and 63000 2RS matches the 10 X 26 X 12. Total for two of each from VXB bearings is $42.71, including shipping.

The lower bearing is secured by aluminum rivets that hold the retaining plate. The upper bearing is secured by steel rivets!!!!. There is probably zero load up there, so that surprises me. I'll add notes on the rivets sizes as it plays out.
 

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Discussion Starter #3
I can easily see the yellow dot on one of the advance weights, but see no matching dots on either the pivot pin or the points cam fork as described on the Montreal web page. Anyone know another way to ID these matching elements?
 

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Discussion Starter #4
Pics and update

Here are some pics from the beginning of the job.

Meanwhile, I took delivery of the MR181A Pertronix kit based upon the guidance of the Pertronix tech department. Unfortunately, the guy that helped me goofed, and the magnetic rotor that slides over the 4-lobed cam in the S137C does not fit. His recommendation was to use a Dremel tool to open it up until it did. After thinking about this, I decided on a better course.

Meanwhile, the base plate that carries the two Hall effect triggers fits onto the Marelli base OK, but clocked at a somewhat different angle than the original points. Thus, if I use them, I would probably need to remove the distributor drive and turn it a bit to engage a different set of teeth on the cam worm gear in order to result in the distributor body being in the original orientation.

Soooooo. Rather than all that bother, I'm going to send my spare distributor to Pertronix who will custom make a set for $250. I plan to do two of them, one for each motor. Not sure if a batch of them would get a better deal for us, but if you are tempted this would be the moment to raise your hand(s).

Below you can see that the drive gear in the drive housing was SHOT. The support for the input shaft is a puny 6003 gear and the end of the shaft that is inserted via rubber bushings into the drive flange on the bottom of the distributor. I'd say this bearing is under-specified, and is likely to contribute to rapid wear of the both the cam output gear and the drive-body input gear.
 

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Discussion Starter #5 (Edited)
Advance weights

The timing advance was pretty much locked up on this dizzy. Careful cleaning and some high-temp grease seems to have it happy.

The circlip that holds the point-cam in place broke during removal. I've ordered 100 from McMaster Carr.

The two-jaw puller is NOT what I ended up using. After tinkering with it, I decided there was too much risk of putting a bending force on the edges of the flange, and scratching the drive gear on the input shaft. So, I used a tie-rod puller commonly found at Horrible Freight. The slot in one jaw perfectly straddled the shaft for the input gear, and it fit up under the input flange on the dizzy, spreading the load nicely. Both came right off. Replacing the driven gear was fun, as I froze the input shaft (with bearing) in the freezer for several hours, and baked the driven gear at 450. It would NOT slide on by hand, but dropped on until the shaft was about half-way inside the gear. Fortunately, I had lined up the split-pin holes well, so after pressing the gear the rest of the way, I was able to drive the pin back into place. I reckon it wouldn't do things any good to have to remove and replace them several times just to get the holes lined up.
 

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Discussion Starter #6
I've been beavering away on the second dizzy. The first has gone off to Pertronix to have a kit made for it, plus another kit for the second distributor. I've heard from one fellow that wants one, so I guess they'll be making three of them.

It was a bear getting the bottom bearing off of the second distributor shaft. In the end, I had to break the outer ring, remove the balls, and use a bearing-divider to jig it all up in the press.

After getting #2 assembled, I realized that I had left off the snap ring at the bottom of the lower bearing. That required removing the input spider again, but it was hard to do the first time, not the second.

The #2 drive assembly (the part that attaches to the rear of the head) was something of a mess. The bearing wasn't too bad, but I changed it anyway. However, the tip of the drive that fits into a bronze bushing in the bottom of the drive seemed to have a high spot on it, or perhaps the shaft is very slightly off-axis. I used scotch bright and very light emery paper to remove a few ten-thousandths, and polished up the bushing, and it came good.

Got lucky reinstalling the gear again. I'd hate to have to re-remove it several times just to line up with split pin.

The freezing of the shaft and heating of the gear seems to do no good. Maybe slightly, but the chill quickly shrinks the gear and that's that. It has to be pressed into place.

An so it goes.
 

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Discussion Starter #7
Does anyone know a source for the circular rubber seal that fits over the distributor drive assembly that seals it at the back of the cylinder head? This was not included in my new gasket kit. Why, oh why, do people advertise full gaskets sets as full when they are not?
 

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Don, you don´t will find it to buy it in a shop. This rings not available.

Dave Bramwell from Canada produced it for the Monti comunity. Maybe he have some left.

kai

Sorry for my poor english.
 

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Discussion Starter #9
I have tried to find contact info for Dave Bramwell without success. Can anyone help?
 

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Discussion Starter #11
Kai,

Thanks. Inquiry sent.
 

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Discussion Starter #12 (Edited)
Marvin at Pertronix told me just now that my units will be shipped today, as well as to Charles, another buyer. It took a month from the day I shipped the distributor off to them. They charged $250/kit, which is not far off from the other S137 kits they offer (Lambo, Ferrari, etc).

Marvin also confirmed that the Montreal will now be in their 2015 catalog under part number MR185. I don't know the proposed price. A little more or less won't be a big deal.

If anyone else wants to jump into their distributor, it's not very hard so long as you have a good hydraulic press and riveting tools. I have a large box of the steel rivets used to hold the top bearing retainers in place, and will happily drop a handful into an envelope if anyone wants enough to do their dizzy.

The lower bearing is held in by rivets as well, but I used some aircraft rivets that I already had in stock. Don't recall the size.

The bearings are easy to find and cheap, so there really is no excuse for not renewing them if there is any doubt. Ditto the single ball bearing in the drive assembly.

As a note....

The Pertronix kit has fixed phasing on the two induction units. I assume the original points are adjustable due to the potential for wear on the rubbing blocks and steel drive cam. As the Hall effect units will have no wear points, and the drive cam is covered by the magnetic trigger, the phase can be set permanently. Thus, one should have only the timing to deal with in routine maintenance, and that is unlikely to change unless something worrisome is going on with the cam drive gears or cam timing.

Lastly - a question....

Optimally, the rotor should be pointing in a very specific direction when everything is assembled correctly and the timing is correctly set for cylinder #1. There is only so much advance/retard adjustment on the distributor, so I'm wondering if anyone knows the trick to setting up the cam-to-dizzy drive unit so the distributor will drop into the right orientation? I can imagine that having the cam/drive unit worm gears off a single tooth could make timing a problem due to insufficient adjustment span. The drive unit is a PITA to get on and off, so I'd rather get it right the first time.

I seem to recall that the cam can be shifted forward enough to disengage it from the dizzy drive (although not removed with the drive assembly in place). Perhaps this is what allows one to assemble the drive assembly to the head and make adjustments to the cam/distributor phasing?
 

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Discussion Starter #13 (Edited)
Added notes...

As other people might come here when rebuilding only their distributor and/drive unit, I figure it might help to add a few notes about the drive unit.

It turns out that it can be removed and replaced only if the exhaust cam has its bearing tops removed and the cam slid forward. As I was focused only on the cam when taking it apart, I didn't notice that the drive unit had to be re-installed before the cam was bolted into place. Not a big deal to remove the cam again.

The drive assembly bolts (4 of them) are a 7mm thread with 11mm heads. I suppose this is because they are required to hold the drive body against possible rearward loads, so needed to be bigger than the 6mm/10mm bolts we might have expected there. All four can be reached with a 1/4" drive ratchet and 11mm socket, although the upper right side (passenger side) bolt is a bit annoying to reach and stay on. I gave up trying to get an air ratchet back there.

As the cam drive gear nuts like to be loctited, it is best if the cam timing is done before the right side exhaust cam is buttoned down in the head. I ran through a process of hooking up the right timing chain with the intake cam rotated where none of its lobes were opening their valves, made sure the engine was at TDC-compression for #1, and buttoned down the exhaust cam with the timing marks lined up. Then, after releasing the chain tensioner, I tightened the cam gear nut, and found the hole to slide the fixing bolt through. We'll see if I got it right when it's all put together. The exhaust cam can be loosened and lifted up and forward, but not out of the engine once the drive assembly is bolted in place.

The drive assembly needs to be "phased" to the exhaust cam. This could be done with the driven shaft not yet installed, but as I already had that assembled, I went through the drill of stabbing the exhaust cam in place with the drive assembly bolted up, then dropping the cam into position with the timing marks lined up. As this position has one of the lobes attempting to press open a valve, the best that can be done is to get the front cam journal near to the front bearing saddle, with the bearing cap dropped as far down as it will go to see if the two marks are aligned. On my distributor there is a scribed mark along the edge toward which the lower rotor tip should be pointing (#1 firing position) when the cam is set according to its timing marks. If you haven't mated the correct teeth on the cam and drive assembly shaft, it will be off by enough that there is no ambiguity.

I have discovered that all four cams on the Montreal can be laid in place such that none of them are depressing valves, allowing the engine to be rotated to whatever position is desired. However, as with all Alfas, you must have the engine in a position so that none of the pistons on that particular bank are at TDC while going through a shim adjustment exercise. I prefer to lay them in this position when tightening up the cam caps to make it easier, but as this position is no where near to having the timing marks lined up, there is some interesting guess work as to where to position the crankshaft. For the final assembly, I plan to have each bank at TDC and tighten with the cams at or very near to their timing mark locations.

Here's some relevant pics kindly provided by another BB'er (Charlie L) to help me get oriented.
 

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Discussion Starter #14
Pertonix....

I received my distributor along with its installed Pertronix ignitor. Just in case you are wondering, of the three types they offer, only the Ignitor 1 is relevant to our needs, and is the unit to be offered in the MR185 in their coming 2015 catalog. The Ignitor 1 is just a Hall-effect trigger, with no fancy additional features. The II and III (or whatever they are called) use sensors that measure the coil load, among other things, to change timing, spark duration, etc. Not relevant to our CD ignition.

I have have installed, but not timed, the distributor. Before getting that far I want to sort out the wiring to make sure it is both correct and attractive. The Pertronix unit has two permanently attached wires coming from each Hall-effect sensor, which are then stuck through the side of the distributor through rubber grommets. No more plastic insulating piece or rusty, easy-to-lose 8mm nuts. The original uses only a single wire that heads off to the CD units, but the Hall effect units connect their ground separately. Pictures and description will be provided when I have that wrapped up.
 

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Discussion Starter #15 (Edited)
Quick update, but more to certainly follow.

I purchased two kits from Pertronix, one already assembled in the distributor that I provided to them. When I attempted to start, it wouldn't. This was solved by swapping the coil leads, but I was certain I had connected all of the relevant wires to the A and B systems as required. After thinking about it overnight, it occurred to me that perhaps Pertronix had the pickups located incorrectly, and that the B wire was exiting the A hole, and vice versa, My foggy brain also thought maybe that doing this would result in timing/phase issues as the pickups are located 45 degrees apart.

After the engine started with the swapped coil leads, it ran but had a noticeable miss. I drove the car, but was happy to make it home with the miss.

Today I took pictures of the distributor insides as supplied by Pertronix, as well as my other distributor with the stock points sitting in their original positions. It is clear that Pertronix has chosen a different pair of locations for their pickups, but as the plastic magnetic ring could be timed differently I can't say whether that, in itself, is a problem. However, I have definitely determined that the kit, as provided, has the A pickup exiting the B hole, and vice versa. So, I swapped the coil hi-tension leads back, as well as the pickup trigger wires. Car started, but miss still present.

So....

I assembled the other kit into my other distributor, and installed it. Starts and runs fine with no miss. Provisional conclusion #1, I have a defective pickup on the first kit.

However, the engine won't idle. It just dies slowly. This was previously solved by getting the timing right. When I attempted to time the first kit (with the defective pickup), I got a very jumpy signal and jumpy AM timing mark. At least, I THINK it was the AM mark, but it was too jumpy to tell.

When I attempted to time the second distributor no timing marks at all came into view. Engine running very smoothly, but perhaps not as much "zing" on acceleration in neutral.

I'm betting that the Pertronix pickups are positioned in a way that won't let me time the distributor within its current limits. This might be cured by re-stabbing the drive into the cam drive gear. However, before I do that, which is a fair amount of work, I'll be speaking to Pertronix.

Charlie - I wouldn't attempt to install your Pertronix kit just yet. There is work to be done.
 

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Discussion Starter #16
You guys are being nice to me. Why did I make the header "S137" distributor? It's an S127. Maybe a mod will change it to help future searches by a needy Montreal owner. Hmmm. That doesn't narrow it much. We're all needy.
 

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Discussion Starter #17
Need a quick-ish reply...

I know the distributor is mounted on the left bank when in a RHD Montreal. Does the distributor rotate the opposite way to our LHD cars? I'll share the funny reason I'm asking once I get an answer.

I know that on the 1900 and 2000 (cast iron) cars, the distributors rotate in opposite directions depending upon which cam is driving them. I'm wondering if the Montreal has the same quirk?
 

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Discussion Starter #18
I heard from Garrett Weaver at Pertronix earlier this week. Yep, they got the plate timed incorrectly. Although I found the tech-desk help at Pertronix to be not much better than the typical computer help-desk somewhere in India, Garrett knows his game. He's the boss of the tech/R&D group, so that's as it should be. I understand new bits are on the way, and assuming it works as promised, he'll get the second one off to me, and I assume the other customer(s).

I'll report back when it's all up and running.
 

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Discussion Starter #19
The new plate arrived from Pertronix today. It was a very simple matter to swap the pickups from one of the first plates to the second, and drop it all into the distributor. I could have done that without removing the dizzy, but it is so easy to take the dizzy out of the car that taking it to the bench was a better plan. Kept me from bending over the engine bay, among other things.

The clearance between the pickup mounting holes and the studs in the plate is very close, so there is essentially no chance of wiggling them out of their intended timing spot. The wires lead naturally to their intended A and B exit holes, which fit the provided rubber grommets nicely.

As I had already terminated the pickup leads with barrel-plugs, they snapped straight into the waiting harness. I tried the setup once with about 90% advance set in, as that is what it had been taking with the points. Oooops. Too much. Reset the diz to the midpoint of the slot, and the max-advance fell dead in the middle of the line on the inspection hole. Very steady timing light, as well, which was an improvement over the points.

I have yet to sort out some other idling issues, but I can tell that we're on the right track.

Not sure if Pertronix is shipping the kit yet, or whether you'll have to wait for the 2015 catalog. My experience with the setup on the 102 is what convinced me it would help the Monty, and first impressions (well, second impressions) are favorable.

Here's a pic of the early and late plates. First, mis-timed one on top. Correct one on bottom.
 

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Hi Don, I am just jumping into the distributor and your information is extremely valuable! I am wondering if you still remember or have some info about the size of the 3 bolts that attach the distributor to the back of the engine head (LHD). I am not finding them.
 
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