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I´ve been reading this thread with great attention as I am planning a tranny rebuild. I own an Alfetta and wanted to know if this mod applies for transaxle cars.
 

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But Mad North-Northwest
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I´ve been reading this thread with great attention as I am planning a tranny rebuild. I own an Alfetta and wanted to know if this mod applies for transaxle cars.
The Milano, at least, had a different setup. There's this goofy spring-loaded bit on first gear (parts 5-7 in the diagram) that theoretically engaged the synchro but didn't actually work well at all in my experience.
 

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I agree with the comment on the weird spring in the Milano 1st gear synchro. That spring actually broke in half in my transaxle and jammed the synchro. Made it impossible to shift into 1st gear. Had to disassemble the tranny and synchro to fix it. Stupid design.
Jim
 

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Let the Good Times Roll

Thank you 60sRacer and Alfar7, and everyone else who has contributed to this thread, for your great instructions. I have just pulled the transmission from my 1989 Spider Quad to replace a leaking input shaft seal and leaking differential seal. I will have to make the castle nut removal tool and have a 30mm socket for that purpose.

The second gear does grind a bit if shifted too quickly. You have given me the self-confidence to do the first gear fix and have a good look at the second gear. Fortunately, I bought a spare transmission a few years ago that I can use for any needed parts. I will post an update once the operation is completed.

Regards,
Chuck

1989 Spider Quad in Alfa Red on grey, 49k miles
 

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I'd like to merely say thanks to everyone who posted on this thread - and the the fix was a stunning success! Less grunch than a modern car after the fix and a fresh fill of redline.
 

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Hello All

New to the site and in the process of making the mod. The thread is informative and amusing. Oh, the Milano gear box will sit in a GTV6 frame. Can't wait to drive it.

Thank You
 

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Discussion Starter #149
Yes. You have set up the synchro bits correctly.

I have not personally tried the fix using the same 1st gear dog (with 2 openings) because mine were always shot, but you should not have a problem with the way you have it assembled.
I ( the originator of this fix) did this to my 1600 transmission in 1971. I've driven it at least 100,000 miles since with no trouble. And I did not change the dog tooth set, so mine is exactly like yours.

You should note that while you have your TX apart, replacing the 1st and 2nd dog teeth is a good idea. Typically the sharp engaging teeth get worn down on these two gears way ahead of the others. You can get good replacements from APE (see suppliers list), or you can swap your 5th gear dog set - which is usually nearly pristine - for your 1st or 2nd gear set.

There are NO new or NOS dog sets available!

Robert
 

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There are NO new or NOS dog sets available!

Robert
Robert,

Thank you for conceiving the concept, (and posting the method of achieving) a synchromesh first gear for our Alfa Romeos.

I implemented this improvement when I rebuilt the gearbox in my Spider and it worked perfectly (and still does by the way). I used the best spare dog gears I had between my box and a donor box because at the time I did the work (4 years ago) there were not any sources for new dog gears. But it seems that Centerline has found a contractor capable of producing them, and although I have not personally tried this new batch, Centerline is offering them to the public now (but at a premium).

https://www.centerlinealfa.com/catalog/gear-dog-ring
 

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For anyone using thread as a reference for the 116 transaxle, keep in mind that the photos in the first couple of pages are from 105 boxes. The 1st gear mechanism in the 116 is assembled the other way around as the gears are meshed in the inverse direction. It should be obvious by the angle on the larger notch

105:


116 (early):
 

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And for another variant - how about an old-style/non-moly synchro gearbox (aka Dentax box) found in early 105 and 101s.

Could someone confirm that I have placed things in the right place for this old-style gear?

The top hat, etc. in these old ones is a different shape, so there aren't any comparison pictures for this type out there. Pretty sure I have it right, but confirmation would be helpful.

Also, I did not replace the dog gear as it is in fine shape (and I am also out of good 2nd-5th dog gears).

Look correct?
 

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Thanks for the confirmation. And another version of Alfa gear added on the thread.
 

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I posted a thread about fixing the famous 'First gear Grunch' a while ago. Just send a PM off to a member that asked about it, and thought some others might be interested.

The issue is that when sitting at idle and not moving, the first gear will grunch when shifting from neutral to 1st. It's because of the way alfa saved 3¢ in assembling the transmission. It'll cost you about $15 in little bits of alfa parts (or free if you have a spare gear or two), and a lot more agrivation than it should. I did this almost fourty yeas ago and it is still working fine:





If you take those awfully strong snap rings off each gear, you would see the pieces that make up the syncro mechanism inside the moly ring. There is a small key at the top, and a longer one at the bottom, with two arc shaped pieces on either side. The top piece keys into the outer molly ring (that's why there is a gap in the ring), and the bottom piece keys into a notch in the gear itself. The two arc pieces essentially connect the two keys.

Friction on the molly ring from the brass syncro slider pushes the top key, which pushes on the arc piece, that then pushes on the bottom key. The bottom key fits in a notch in the gear and so pushes on the gear. All this occurs before the teeth of the brass syncro engage the dog teeth on the gear. So all this serves to speed up the gear to match the rotation rate of the brass shift slider.

The second arc piece inside the gear is for the 'upshift' case, where you need to slow down the gear to match rotation rates.

Except for first gear. This gear only has one arc piece, and the top and bottom keys are different. The result is that the 1st gear will sync only on a downshift, when you want to speed up the gear. Well, of course you say. Who would ever 'upshift' into first? But that's what you do when idling in neutral with the car at a standstill; the gear is rotating, and you need to slow it down - or 'upshift' - to engage.

We all have learned to lightly touch second before engaging first when standing still and in neutral. That syncs second on the virtual 'upshift' from neutral ( that is, the rotating gears stop), and then 'downshifts' into first.

I got tired of the obvious grunch almost four decades ago. I just took all the bits for another gear (they are all the same after 1st) and put them in the first gear too. There is a slightly larger notch in the first gear; I thought about welding it up, but didn't and there has been no problem.

For 37 years!

AND NO MORE GRUNCH! Just do it.

Robert

BTW - you can remove the dog teeth bit from the gears. It's tricky, but it's just pressed on - very tightly. This is how you renew a worn second gear syncro. Take a dog ring off a spare fifth gear (they are all the same) which rarely wears much.

Enjoy

Robert
The first gear mod is great we took out about a pound oR so from the rotating mass of a 1ST, 2ND, 3RD
 

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Very useful thread which I found the very correct moment as I am rebuilding my 105 gearbox having the problem of 1st gear...
I posted a thread about fixing the famous 'First gear Grunch' a while ago. Just send a PM off to a member that asked about it, and thought some others might be interested.

The issue is that when sitting at idle and not moving, the first gear will grunch when shifting from neutral to 1st. It's because of the way alfa saved 3¢ in assembling the transmission. It'll cost you about $15 in little bits of alfa parts (or free if you have a spare gear or two), and a lot more agrivation than it should. I did this almost fourty yeas ago and it is still working fine:





If you take those awfully strong snap rings off each gear, you would see the pieces that make up the syncro mechanism inside the moly ring. There is a small key at the top, and a longer one at the bottom, with two arc shaped pieces on either side. The top piece keys into the outer molly ring (that's why there is a gap in the ring), and the bottom piece keys into a notch in the gear itself. The two arc pieces essentially connect the two keys.

Friction on the molly ring from the brass syncro slider pushes the top key, which pushes on the arc piece, that then pushes on the bottom key. The bottom key fits in a notch in the gear and so pushes on the gear. All this occurs before the teeth of the brass syncro engage the dog teeth on the gear. So all this serves to speed up the gear to match the rotation rate of the brass shift slider.

The second arc piece inside the gear is for the 'upshift' case, where you need to slow down the gear to match rotation rates.

Except for first gear. This gear only has one arc piece, and the top and bottom keys are different. The result is that the 1st gear will sync only on a downshift, when you want to speed up the gear. Well, of course you say. Who would ever 'upshift' into first? But that's what you do when idling in neutral with the car at a standstill; the gear is rotating, and you need to slow it down - or 'upshift' - to engage.

We all have learned to lightly touch second before engaging first when standing still and in neutral. That syncs second on the virtual 'upshift' from neutral ( that is, the rotating gears stop), and then 'downshifts' into first.

I got tired of the obvious grunch almost four decades ago. I just took all the bits for another gear (they are all the same after 1st) and put them in the first gear too. There is a slightly larger notch in the first gear; I thought about welding it up, but didn't and there has been no problem.

For 37 years!

AND NO MORE GRUNCH! Just do it.

Robert

BTW - you can remove the dog teeth bit from the gears. It's tricky, but it's just pressed on - very tightly. This is how you renew a worn second gear syncro. Take a dog ring off a spare fifth gear (they are all the same) which rarely wears much.

Enjoy

Robert
Thank you so much for the excellent thread. I found it the very right moment as I am repairing my 105 gearbox to fix the 1st gear issue. At the beginning I thought that would be enough to replace the wasted syncro ring but now I see the opporunity for real improvement. I went carefully through all posts of the first 3-4 pages and I have a question, as I am confused a little bit... My syncro ring has its teeth wear so definitely needs replacement but 1st gear dog ring seems to be ok. So, are the below steps the correct ones?

1. To replace only the synchro ring and keep the existing dog gear in use.
2. I understand that I shall replace the stepped key with one like 2-5 gear style
3. And finally to add to the opposite (empty) side a half ring same like the other one.

My doubt, if I am correct, raised because someone said the dog ring shall be replaced as well and to be the same style like 2-5 gear because parts are not interchangeable but what is the difference? I understand so far that all dog rings are same, am I wrong? As I have no any used spare parts in Greece I shall look in the online market for new (expensive) parts, so I like to be sure what I am doing! Thank you in advance for any reply!
 

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Richard Jemison
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You can use the dog gear assembly but best to replace all the internak "brake" parts with those from a 101/105/115 2nd through 5th syncro assembly. The single band in the 1st gear is too long to use in the corrected assembly.
 

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If memory serves the 1st gear dog ring has a slightly larger gap between where it begins and ends. But it doesn’t matter for the first gear fix you are doing. You can use the original first gear dog ring or a replacement from 2-5th.
 
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  • You can use the dog gear assembly but best to replace all the internak "brake" parts with those from a 101/105/115 2nd through 5th syncro assembly. The single band in the 1st gear is too long to use in the corrected assembly.
    I just found one gear box like mine for really good price, so I will use for spares and I will do the 1st gear fix in the best combination.
 

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Discussion Starter #160
The best choice is usually to use 5th dog gear witch usually has its dog teeth in the best condition of a TX. From your TX, that usually means the 5th gear dog set from your TX to replace your most worn one (mostly either 1 or 2), then find a good set of some gear (most likely 3rd or 4th) from another TX for your 5th. This fix has been done so much that good 5th gear dog sets are getting hard to find and we are left with using our 5th where most needed and another TX 3rd or 4th for our 5th to upgrade.

I started this upgrade in 1974*, so there have been 46 years of consumption of 5th and 4th gear dog teeth sets.
*but only shared it with some local NorCal Alfisti where I was [Stanford] until the 1990's when the internet became widespread and I published it there.

Robert

P.S. I am still amazed that Alfa made 1st gear unique - it obviously cost more in unique parts to do that , yet made the TX worse all the while. And it took me less that an hour or so to derive the "fix". Most of that was trying to figure out why Alfa was so dumb.
 
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