Starters and Ring Gears

[alfabender]

Help me recall how all this works:

stepnose --> 1600 engine --> floor mount pedals --> 105 tooth ring gear --> 2 bolt starter --> 8 tooth Bendix

smoothnose 1750 engine --> hanging pedals, hydraulic clutch --> 130 tooth ring gear --> 3 bolt starter 0.9 hp --> 9 tooth Bendix

smoothnose 2000 engine --> hanging pedals, hydraulic clutch --> 130 tooth ring gear --> 3 bolt starter 0.9 hp --> 9 tooth Bendix

Later than 1974 --> hanging pedals, hydraulic clutch --> 131 tooth ring gear --> 3 bolt lightweight 1.25 hp starter --> 9 tooth Bendix, works with 130 tooth ring gear but not the other way around

Do I have this right?

Also I have two oddball starters in my collection:
1) 2-bolt, looks like early style, but 9 tooth Bendix
2) 2-bolt, 8 tooth Bendix, but casting at front is different and solenoid comes off at an angle away from the engine instead of snug up to it, and fouls the throttle linkage.

Any idea what either of these is?

Doug Bender

[Alfajay]

-Doug:

Yea, your four major examples match my understanding. I can't explain what those two "oddball" starters in your collection are, however.

Two comments on your list of the four major configurations:

- I have heard that some of the late mechanical clutche cars came with a 3 bolt starter. Probably still with a 105 tooth ring gear, 8 tooth Bendix, but the bellhousing and starter housing had the third bolt. (For extra points: Is this a "shoulder" bolt?).

- You note that the early and late 2 liters differ in that the former has a 130 tooth ring gear, while the latter has 131 teeth. You note that these came with different starters, but both have 9 teeth in the Bendix. You note that the early starter cannot be used with the late ring gear, but suggest that the converse would be OK. I dunno - I'm skeptical that these can be mixed in either direction without chewing up the ring gear eventually.

[George Willet]

Flywheel and starter motor identification;

Year Engine cc Flywheel Bendix Casting Number Notes.

’65/up 1600 105 8 001-211-004 .7hp- same internals as 1750, but two bolt mounting

’69GTJr 1600 105 8 001-211-016 Mechanical bell- housing, three bolt mounting

69/71 1779 110 8 001-211-016 .7hp- three bolt mounting

72/74 2ltr 130 9 001-211-987 four brushes/2 bolt solenoid 001-211-025 two brushes/2bolt solenoid. Both .7hp w/3 bolt mounting.

‘75/up 2ltr 131 9 001-311-110 1.1hp/3bolt solenoid/must rear brace to motor mount.

The 001-311-110 starter will work on the 130 tooth flywheel, but without the rear brace it will break the bell housing, as it is much heavier than the earlier starters.

The 1600cc flywheel is (about) ½” smaller in diameter than the 1779/2ltr flywheel, so the mechanical/1600cc mechanical bell housing will not fit over the 2ltr flywheel, even though the bolt pattern is the same. And there is no starter that will work with a hydraulic bell housing on a 1600cc flywheel.

Using 1600cc flywheel on a 1779cc engine to mechanical bell housing will work, but you have to use the three finger clutch, and it doesn’t hold a lot of torque when the disc wears.

So if you want to use a 2ltr engine with the mechanical bell housing, (or a 1779 with a diaphragm plate,) then you have to use an aluminum flywheel with a 105 tooth ring gear and an 8 tooth starter. You now have the choice of using the hydraulic pressure plate (diaphragm) which holds torque very well, or the three finger clutch plate; you order it either way.

I order flywheels from Fred at Autostrada, 1-360-588-8311.

Hope this helps.

[Alex]

George,

So if I'm reading this correctly ...

If I wanted to construct a Franken-clutch for my 1750 engine I could, in theory, use a 1750 gearbox, 1600 bellhousing, 105 tooth ring gear, 8 tooth starter (or lightweight modern alternative) and still have the benefit of the hydraulic clutch plate (still actuated mechanically, though) provided I have a special flywheel made? And does anyone have an AUTOCAD (etc) file of this flywheel design? Is a special throw-out bearing required too?

Or is this just unnecessary for a moderately warmed-up engine - in which case it's just more simple to retain the 1600 three-finger mechanical clutch and flywheel?

I'm not fully sold on an alloy flywheel for street use as my car will need to cope with all eventualities, but at the same time I do want to stick with the mechanical clutch actuation instead of plumbing in more hydraulic lines.

Have I got this right?

Alex.

[rafael]

George:

Thanks for the info. I have been looking for this info for a while, sinde I have to buy a starter for a 2000 engine I bought.

[60sRacer]

I don't think a special flywheel is needed. I have a 2L engine in a Duetto. 1600 transmission, 2L flywheel (I forget which one) with the 1.1 HP starter. I use the starter support at the rear of the starter (tho' it's forward in the car). I put in a Porche racing pressure plate and disc in place of the stock 2L assembly, but they are identical except for spring pressure (very hot engine). I use the 1600 mechanical clutch bellhousing and the Centerline T/O bearing adapter to actuate a hydraulic T/O bearing with the mechanical linkage.

Never changed the bendix on the starter; I never counted the teeth on the flywheel, but it was the stock one from a 1974 2L engine. Starter has three bolts, but the bellhousing only has two.

It's been working fine for 30 years. Clutch peddle pressure is heavy for stop-n'-go driving, but gangbusters for hard laps. I like it mutch better than the hydraulic clutch for fast double-clutching - it's much more precise with very good feel.

Robert

[lgowin]

When I assembled my GTV (bought it in boxes), I built a 2 litre from an Alfetta but I had a pinion/ring gear mismatch. IIRC, I was able to have a different gear pressed onto the starter.

Regards,
Lawrence

[George Willet]

Robert, the 1600 bell housing is smaller in diameter that the two liter ring gear, so the ring flywheel had to have been machined to accept a 1600 ring gear, then it will work as you described.

I am working out a 1600 engine/flywheel with a 1750/2 ltr bell housing installation as the car (a Super) has been converted to a hydralic pedal box in the past. So far it looks like with just a small amount of machining, it will work.

[60sRacer]

George,

I know that that is the way it is supposed to be. But the flywheel is a fully stock 2L, with its original ring gear. I'll be taking it apart later this year to verify, but AFAIR it's fully stock.

The flywheel is larger than the original 1600 one all the way to the ring gear. The starter ends up farther out than original. But I'm using the steel interface plate - between the bell housing and the engine - from the 2L, and the starter mounts in the 2L position to mate with the flywheel. The bolt holes in the bell housing all fit. The starter barely fits in the nose opening of the bell housing, and the ring gear has made a shallow groove is a small portion of the bell housing, so it is a close fit.

There is some hint that the bell housing is not stock 1966 Duetto. It appears to be a 1968 Euro car, perhaps with the 1750 mechanical clutch bell housing (I didn't even know there was such a thing). It's a bit odd casting in that it has the large openings of the column shift mounted mechanisms (from the sedan). But we know that Alfa had a habit of assembling cars from whatever was on hand at the time; for example, the car also does NOT have the single brake booster found on some Duettos, but it did come with ATE brakes.

Anyway, my comment is that there are at least some configurations that work without custom flywheels.

Robert

[George Willet]

OK Robert: I am down to the shop to test this out!!!! Will report later.

[rafael]

George,

I have a starter of the following type: 001-211-207. No you happen to know what kind of starter this is, and if it will fit in a 2000 engine with 130 flywheel?

Thanks in advance

Rafael

[George Willet]

I do not know what that fits, Rafael. Someone else know what it fits??

Robert. The bell housing must be what you think it is: a mechanical linkage 1750 unit, as the 1600 bell housing won't fit over a 1750/2 ltr ring gear. I tried.

[60sRacer]

Thanks George. I suspected as much. Just blind luck that I had the right parts when I swapped in the 2L engine, 'cause there was no BB then. I did have Larry and Larry Jr at APE for guidance though....

Good thing - the mechanical clutch linkage is really nice on a high performance engine much more control than the hydraulic ones I've tried.


The key then is to have the right bellhousing - a 1750 floor pedal & mechanical clutch bellhousing makes a 2L a drop in for a 1600 motor. The carb support rod is longer by about 6 mm - I cut mine and welded in a spacer, but eventually replaced it with one from a 2L, supplied by Centerline, who also supplied the TO bearing adapter to use the diaphram clutch disc with the mechanical linkage. The only hard part is the exhaust. The cast iron headers are fine, but it takes just a little work to get the front downpipes to fit around the pedal assembly. I had a muffler shop heat and bend the ones I got.

Then do all the neat things to make for a hot 2 L motor. I also stuffed in a 2L diriveshaft and LS rear end; more bolt in swaps. And the 2L front spindles in place of the 1600 short ones with the larger 2L front discs and calipers. Had to give up the campy right and left hand lug nuts that the 1600 Duetto came with, but I had to do that for the Panasport wheels anyway.



Robert