Inside 308 distributor: Is this normal ?

I finally took a peek inside the ditributor. 1978 GTB (Euro).
The rotor is held in place with a bolt and a wire. Can't say that I ever saw this before.
Is this normal ? (The rotor is loose too !)
... or is this someone's attempt to hold an ill fitting rotor in its place ?
I have wired oildrain plugs for motorcycles, but never ditributor rotors.

I notice from the owner's manual that there was an optional magnetic pickup ditributor available for this car, but somehow I sense that this one was retrofitted with the magnetic pickup. The distributor is a Magneti Marelli "S 159 B" which is not one of the listed options in the book I have.
Any ideas/education what the history may be on this ignition is greatly appreciated.

Regards,
Hammerson
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It's been a while since I've looked inside my distributor, but, that is definitely not the way its supposed to be! I want to say mine was simply a press-fit.

 

Don't know if there is a difference, but I just changed caps and rotors on my 77 (US Spec) and the rotors were slide off, slide on.

 

Three World Fairs and a Goat Race and I ain't seen anything like that before ................

 

The rotor with a bolt looks typical for some Marelli distributors. I've never seen one with safety wire.

 

Don't know where yours came from. Probably would work fine electrically but not so elegant. Here is a shot from my 78 308 GTS. This set was all orginal as best I can tell. I hope it helps.

-Rjay
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The rotor on a single distributor system is held with a nut and bolt. Early Euro-spec cars had a single distributor with points, later cars have electronic ignition i.e single distributor with Hall pick-ups.
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Are those rotors original to a '78? Looks to me like later.

 

S159B is used on the later US versions carbed 308 with two distributors (and slip-on rotors like in Rjay's photo). I think you could do a lot of mixing and matching with the various Marelli parts -- so having a S159B housing isn't necessarily a bad thing (e.g., the advance curve could be changed relatively easily to match anything you wanted), but a physically "loose" rotor definitely needs to be fixed/improved (like you've got the "wrong" shaft for the twin-tipped rotor).

What are "...the listed options in the book..."?

Do you only have a single coil and a single coil wire going to the dist cap? Does your dist cap have a place for two coil wires (like Mick's SPC illustration) or only one? My guess would be that that twin-tipped rotor (and maybe your cap), although of similar form, is actually from an Italian cousin. Here are some jpegs posted by other Fchatters of the single-distributor euro distributor and rotor (both points based and electronic) -- and you can see that the rotor is somewhat different (and held on by a thru-bolt and nut as Mick mentioned):
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Allright, finally back to answer questions.
This is a single distributor system.
This is a magnetic (no points) pickup system inside this distributor. I.e. electronic ignition.
There is one bolt, but NO nut holding the rotor on the distributor shaft. (See my second pic in initial post.)
I do have a distributor cap that has a single coil wire going to it. But the cap has space for TWO coil wires ! (A and B)

So, I think I have learned from all of you (thank you) that I have a US style distributor body.
The distributor has two exit holes marked R1 and R2, where only one is in use.

One pic here shows the magnetic setup inside.
I do not see any postings showing a rotor that looks like mine yet, so that part of the mystery lives on.
The ignition control box has nothing but a serial number on it. Who knows what it is.
The coil is a "MSD Blaster 2" mounted on a heatsink.
MSD is an American (?) aftermarket brand that I know nothing about.
The MSD web site does not even list Ferrari as a car that they sell ignition systems for !!!???

"Options listed in the book.." By this I mean the 6 x 8 inch booklet called "instruction book".
It has a decent specifications section that lists the Marelli distributor numbers for breaker point and electronic versions. (See pic)

Last question (I think): What about ignition advance control on an ignition system like this ????

Thanks,
H
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The ignition advance is done by a mechanical system inside of the distributor that moves the triggering feature (in your case, the 8 pole reluctor) relative to the input shaft.

 

It looks like you have a mix 'n match system here. Your rotor is a typical type used with a single coil yet the cap has a second terminal that would be meant for a two coil system (and one of the rotors pictured in an earlier post). The MSD coil is okay, no problem here. Spark advance is mechanical and can be adjusted for best performance but requires some disassembly to do so.

 

Your rotor has the narrow electrodes and is for a 12 cylinder car like the BB512. The V8 rotor has wider electrodes like the one shown in post 9.

 

Aaaah. Thanks Rifledriver.
A rotor from a V12 makes sense because the electrodes are indeed A LOT narrower than the one posted earlier.
This probably explains why rotor is held with bolt only and no nut, and probably also why it seems somewhat loose.

H

 

The BB has a larger hollow shaft with a removable threaded bushing in it that the rotor retaining screw threads into. The V8 shaft is smaller and solid with a hole drilled through and through and uses a nut on the other side.

I have one of the V8 rotors sitting on my desk to convert to another application so it is rather fresh in my mind..

 

My 81 twin distributor has bolt on rotors and that wire is probably a great idea. One of my bolt/screws came out and destroyed the cap and rotor. I used locktite on the screw this time and good so far. the wire in my book is OK.

 

I came here looking for something else and this thread popped up in a search. Looking through, I noticed in the photos an item for future reference.

Obviously this ignition system is cobbled together from various manufacturers, but FYI: the pick-up in the distributor is a Chrysler/MOPAR unit...

I can't identify the spark-box though.

 

Way to go Peter! That could be handy to know in the future, thank you!

 

According to this ebay listing the rotor is as Rifledriver states for a Boxer but may be incorrect size electrodes therefore for V8?:

Ferrari Boxer Engine Ignition Distributor Rotor Magneti Marelli New | eBay

 

Yes, that ebay rotor is for the euro V8 single distributor with two coil architecture (in addition to the extra width, note the second offset "center" pin like the photo in post #9), not a Boxer with a single distributor and only one coil (which is the rotor photo in post #10).

 

This fix for the rotor is common for some Marelli distributors (e.g. for classic Lambos as well). If you take off the bolt in your photo, and the washer, you will probably see a recess, into which the head of a round head bolt fits. A thread for the bolt in cut into the shaft and, accordingly, no nut is needed (and not provided for).

This is a somewhat problematic assembly. Im my Jarama the (original) bolt came loose just when overtaking a Porsche on a country road. Since the rotor then is free to rotate on the shaft, the result was a number of loud bangs and complete loss of power. The bangs scared us all, including the guy in the Porsche, to hell . Luckily the loose bolt did no harm to the internals and after a 10 minutes stop we were going again.

Since then I secure the bolt as well, but not in such a crude manner. Instead I use what is called "Sicherungslack" in German, a yellow coating specifically made to secure bolts. It is applied thick to a part of the bolt head at least and the surrounding region of the rotor, thereby filling the gap also. It works fine, the rotor never again came loose since then. And upon inspection you would immediately see, if the bolt starts to come loose nevertheless.

 

Is the Chrysler pick up a bad thing to use? I would think as long as the mechanical advance curve was set up for the optimum, for the engine it was on it would work fine. I modified distributors on the hot rods using Chrysler guts and had reliable results. Did some machine work and checked it on my distributor machine. Are the US spec 308s set up for emission standards at the time of import?



Ago

 

It's an old Perma-Tune unit which was designed to replace a Bosch HKZ ignition. Can usually be found as a replacement in Porsche 911 cars from the early seventies.

 

Nothing wrong with them. From what I've read, Chrysler was one of the first (but I'm not making any claim it was THE first) to use contactless, breakerless ignition. Of course, Ford had their "Duraspark" ignition systems (which upon further review, I think this 308's spark box is a Motorcraft unit) and GM had their HEI. In fact, Magneti Marelli's electronic ignition used on later, Euro 308s used the exact same GM pickups and HEI amplifiers (which were also used on Fiat 124 Spiders) which you can get at your local NAPA store!

Yes, U.S. market 308 distributors featured a second set of points that were activated by a micro switch on the carb throttle shaft. When in play, they would retard ignition 10 degrees at lower RPMs to reduce oxides of nitrogen. Because of the two distributors, you ended up having four sets of points to adjust (two for regular ignition timing and the other two for retarded timing)!

 

Are you talking about the spark box?

The ignition pick up is definitely MOPAR:

Electronic Ignition Distributor Pick-Up for 1971-1974 MoPar B-Body