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Discussion Starter #1
I want to rebuild my distributor. I think that
this involves bearings, and possibly
advance springs? Anyone ever do this? Is it
this simple, or do I need some kind of press?
Not sure about getting parts, anyone have a source?
Come to think about it Im not sure if I have a
Bosch or a Marelli dist. 1971 GTV 1750 USA version,
anyone know which dist came on this car?

Also I found this elctronic ignition conversion
for older Alfa's. The whole kit goes in the
distributor so you never know that its there,
and thus maintain that stock look!!
Here's a link: http://www.pertronix.com/ignition/ignitor/index.htm

I dont care for the MSD and other brands that
have a very large electronic box that needs to
be mounted in the engine bay.
I also dont care much for the Marelli Plex price
of over $300!! Waaay to much mula. I did have
the Marelli in a spider once, and it did work great.

I might buy one of the Petronix kits, and let
people know how well it worked here. They are
only $70 from Summit Racing. http://www.summitracing.com/
 

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Trained (ex)Professional, , 1953-2018 RIP,
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16,232 Posts
Alfa switched from Bosch to Marelli for the US market in 1969. So you should have a Marelli S103B. You can tell the difference by looking at the dist caps. A Bosch cap is shorter than a Marelli by a couple of inches because the Marelli has the advance mechanism under the rotor while the Bosch advance is in the dist body. You can always just pop the cap and look at the rotor; if it's round, about 2+ inches in diameter and held on with two screws, it's a Marelli.
A nice little trick to check the dist is to hook up a dwell meter, start the engine and note the reading. Now rev the engine to 3000 or so rpm. If the reading changes by more than a couple of degrees, the dist bushings are worn. This isn't disasterous as you can always set the dwell to spec at 3000 rpm and ignore the idle reading and it'll run for years like that. But that's a band-aid. Also, if the dist shaft has ANY side to side play, the bushings are toast.
Disassembly is fairly straight forward and you don't need a press. With the dist on the bench, note the offset of the drive to the rotor. Remove the wire retainer on the drive to expose the drive retaining pin. Drive out the pin and remove the drive. If it's a Marelli dist, the shaft should now come out the top of the body. If a Bosch, the breaker plate needs to come out first, then the shaft.
Since parts are unobtainium (at least for me), the local machine shop gets a call. They can replace the bushings or just knurl the old ones back to spec. Even a damaged shaft can be welded up and turned.
An old hod rod trick (for Marellis) is to replace the secondary advance spring (the spring near the square hole....I think; I'll check this weekend) with that from a late 60s Chrysler Hemi. It gives a bit more total advance and starts advancing at a lower rpm. I've found that the primary springs are pretty much reusable unless physically damaged. If you need one, let me know; I'm sure I have some around here somewhere.
 

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Trained (ex)Professional, , 1953-2018 RIP,
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16,232 Posts
Just confirmed that the secondary advance spring IS next to the square hole. While the primary spring remains a little snug around the posts, the secondary is so loose it appears to be ready to fly off into the cosmic void. Perfectly normal.
 

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Discussion Starter #7
Jim,

Thanks for the photo. If you have any other tear
down photos of the distributor, that would be
very helpfull.

Gonna get flamed for this...Is your Alfa tool box
any less reliable than the Craftsman?:D
 

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Trained (ex)Professional, , 1953-2018 RIP,
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I should have known that the tool box would get all the attention!! Now, for extra bonus points, what model/series did the Alfa badge come from and what are the bolts for?
 

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Discussion Starter #9
Here's my guess:

Bolts: con rod with locking tab washers

Badge: Alfetta?
 

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Trained (ex)Professional, , 1953-2018 RIP,
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Hint on the bolts; there's a total of six, 3 on the leftside and 3 on the right. Notice the small bracket on one of 'em?
 

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Trained (ex)Professional, , 1953-2018 RIP,
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Keven said:



Gonna get flamed for this...Is your Alfa tool box
any less reliable than the Craftsman?:D

No electrical problems with it yet but how'd ya know I store the oil drip pan under it?:rolleyes:

Teardown shots of the dist to follow; probably this weekend.
 

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Trained (ex)Professional, , 1953-2018 RIP,
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Sniady said:
Badge: from a US alfa 73 or 74, from the sqaure thing on the trunk

YES!! Advance to go and collect two quarts of oil. The 115.01 is one of three that I know of. Could be more though.
 

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Trained (ex)Professional, , 1953-2018 RIP,
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Here's a few pics of a Marelli S103BA teardown. Note the offset to the right of the dist drive teeth. The rotor tip is pointing straight down.
 

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Trained (ex)Professional, , 1953-2018 RIP,
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Next, remove the spiralock that retains the dist drive lock pin. In this dist, the lock pin pretty much just fell out. Some pins require a punch to drive them out.
 

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Trained (ex)Professional, , 1953-2018 RIP,
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Once the pin is out, remove the drive, a metal shim and a fiber washer. The shaft will now pull right out the top of the dist.

PS the badge also came on a 105.51, 105.62 and the 105.64 (and possibly more)
Three of the bolts attach the steering box (the bracket holds the speedo cable) and the other three the idler arm assy.
 

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Discussion Starter #18
Jim,
Once again you have provided a wealth of info,
thanks. Where does one get parts for the Marrelli?
 
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