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SYNCRO RING PROBLEMS

We were an Alfa shop before becoming a dealer. As Paul Spruell Alfa we sold some 5000 new and used Alfas. We had MANY gearbox warranty claims. New and rebuilt gear boxes were stiff and balky for a long period of time. The texture of the sintered material on the replacement syncro rings was extremely coarse. When gearlube was changed after the 500 mile interval the magnetic plug would have a long beard of ferrous filings from the syncros.

For years in the Alfa repair business, I had scavenged good used syncros in the shop and reused them in my race gearboxes with great success. So, why not do a few strokes with some 100 grit sand paper and smooth off the new syncros? Our service department gave it a try and it was snick-snick from the get go. By artificially breaking in new syncros the gearboxes lived happily ever after. Without the extreme coarseness syncro life was remarkably improved.

Spruell Motorsport currently sells several hundred reproduction syncro rings each year. With all syncro sales we furnish GB rebuild instructions that include our syncro modification procedure. There has been no negative feed back. We furnish free syncros with OS Giken gearsets and there has been ZERO syncro failures in some 30 sets. Then last week a customer’s new GB blew up really big time. A world renowned race parts vendor talked him into using genuine Alfa syncros with the little yellow stripe instead of our proven quality reproductions that came with the gearset. The builder also ignored the instructions we furnished. It was stiff as hell through the gears and after five laps the 4th syncro pealed off totaling the gearset and exploding the case. The twin plate race clutch probably contributed.

One would think that our syncro modification procedure would have made it around the globe by now. For decades our shop successfully used modified yellow striped syncros. From what we are hearing, the current “Alfa” manufacture may indeed be defective. These failures are likely due to some combination of surface texture, different ferrous coating and not enough strength/spring in the ring. With that said, this Alfa parts vendor recommends that you scrap your yellow stripers and order some of our reasonably priced reproductions…..and, of course follow instructions.
I built a 1600 GB with Paul's synchro rings and OSG gearset. I also replaced the input shaft bearing and several other's as well as I consider them time change items regardless of how they look. Admittedly it's a street car "BUT" it does get driven as hard as I can drive it. I used Paul's Sychro ring prep instructions as well as his very detailed assembly instructions with photos (nice job Paul). Filled the box with 75-140 synthetic oil and ran it for about 1000 miles. Drained it to check the magnet on the plug. No metal shavings at all.. Wasn't completely happy with the shift "feel" (shift transitions) so I went back to 85-140 standard Lucas gear oil. Shift "feel" improved dramtically and engagement is seamless. I realize that gear oil is somewhat subjective other than hard data Richard and other's have put forth in this thread so I have to also attach the disclaimer that: "these are my personal observations and should be taken as such."

I would like to get some intial thoughts as to OSG's integration of Nissan synchro sub assemblies with alfa gear sets? I suspect OSG has a great deal of history with Nissan GB's and came to the conclusion after reading the alfa bb for an extended period of time that enough was enough.
 

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Discussion Starter #23
Hi DDSelwood

I think we have found the solution to the gearbox syncros failures.
David H 105 + Rob B 116 gearboxes are working well.
Billy M 105 gearbox will be rebuilt in next few weeks in time for our Eastern Creek sports car races in late May.
All were complaining about shift problems (mainly 3rd +4th gears) after 80% race pace after a few laps.
No problems on road cars,just race cars.
Lets see if my solution also works on Billy M race box,,but wont know till end of May.

Have tried all the solutions from our very reputable overseas venders parts and modifications,with no results.
I dont see that Giken box the way to go in our categories.

Robert
 

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Great discussion! I want a good lathe and the knowledge to use it so bad I could spit.
 

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Great discussion! I want a good lathe and the knowledge to use it so bad I could spit.

Robert,

Allow me to interpret: "This is very useful discussion! I wish I were in possession of a well maintained turning lathe such that, in the hands of a properly trained and experienced craftsman, quality product could be assured. Would that I was that person."

Texans have a colorful way of expressing themselves - I am fortunate to have a sister that has lived in Dallas for the past 40 years so I can usually understand them so long as they speak clearly and slowly. Not too sure about east Texans though...

;)
 

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Discussion Starter #27
All good gprocket.

Well,I have been rebuilding-reconditioning Alfa 105 series + alfetta gearboxes for near 30 years ,BUT ,I personally hate lathes.They scare me.
I guess someone needs to show me how to use a lathe 1000 times before I am confident to use one on my own.

Hopefully this weekend will be the test on the syncro issue,which supposedly is only in Australia,and not overseas.

gigem,,,please buy a lathe,,so you can teach me how to use it confidently and safely,,and between the 2 of us,,lets make gearsets and engine blocks + heads.

Gigem,,I understand now.

Thanks gprocket

Robert
 

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Hi guys

Here in Australia,many Alfa Romeo race car specialists are having gearbox selection issues with the new type syncros sold worldwide,from all the reputable Alfa resellers overseas.
I built another transmission this week and ordered some bearings from a trusted supplier. Although I still have some NOS aftermarket syncros on hand I thought I'd order some new production parts for inspection.

While one might be able to make synchros from the new parts, they're really bad. The profile and thickness is not consistent with the original design and they are not symmetrical. They are missing the machined bevel at their ends. While I was grateful for suggestions on how to make them work, these are not good parts.

This quality is not acceptable. The supplier can do better.

I took a basic photo with my old camera, showing two of the current production parts with some old aftermarket yellow stripe ones. The yellow stripes, the yellow dots, and the old old plain ones are all consistent and good quality. The current production parts look much worse than the differences visible in my snapshot.

--Carter
 

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Richard Jemison
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Trans issues / modifications to resolve shifting issues

I have been hoarding OEM syncros for a very long time. Attempting to burnish aftermarket junk to get them to work reliably isn`t anthing but a short life fix.

I have a dwindling supply of OEM moly syncros and their matching sliders,
and a good personal:p supply of the best of the syncros the early 750/101/102/106 Original striated syncro rings and center grooved sliders that I only use on race gearsets. (with Redline 75-90 NS only) I would think they would still be used if Alfa wasn`t after cheap fixes to production cost.

The syncro dog assemblies from donor boxes from 4th/5th/ (and sometimes 3rd gear) are the source for the needed swap out to eliminate the unidirectional 1st gear syncro assembly, and most always 2 gears`s assembly as the teeth are blunted.

To insure that the replacement Dog tooth assembly has a long and smooth life
there are some modification to these parts that improve function.

If the internal surfaces of the syncro ring and the two friction bands are bead blasted to eliminate the polished surfaces that will improve the "gription" between them to syncronization.

If you feel the tip of the "used" syncro teeth`s points you can feel a burr on the top of good ones, and worn ones will have a spike upwards that enhibits the slider from engaging quickly, and worse pulls out on the syncro on disengagement. (Syncro failure!)

If you look closely at the syncro dogs in the pic you will see I have polished a small taper on the upper points outer part to chamfer and ease the sliders engagement.

I debated sharing this but what the hay...

As well the long standing problem of drilled gears and lube foaming has been long discussed.

I lighten differently than others. while syncro parts are off I backcut both sides of the gears heavily & the taper of the cuts have resolved that foaming issue.

Hope this helps...
Rj
 

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Synchros and racing.

I think that is the problem. To race a car properly you need to blip on the down changes so as not to unsettle the rear wheels (assuming rear wheel drive). Yes I know we are supposed to use the brakes to slow the car but you still need to blip so the engine does not get a fright and lock the rear wheels.

Doing this is simply fighting against what the syncro is trying and designed to do, thus surely for a full race car it is better to leave them out (is that even possible?) and run the gearbox like a dog box.

When my Alfa is finished I will blip on the down change because I love doing it, but I will be wearing my synchros out doing this.

Yes I know this is not the problem but are we doing the right thing trying to make racing boxes with synchros is my point?
Pete
 

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Discussion Starter #32
Hi Pete.

Maybe you should have a look at the start of this thread.
There is an issue with the current supply of syncro rings,especially in racing applications.
Hey,its nice to say =dog boxes,Hollingers,sequentials,hewlands etc,,but most of us are club racers with budgets.
Forget about the budgets,,In over 30 Years,,there has never been a problem with gearboxes,engagement,the way people abuse,upshifting and downshifting,matching revs etc.
There is a problem with current syncros Pete.
Your input is noted,,but you dont have the problem like many in Australia and around the WORLD.
Many are NOT contributing to this discussion,in fear of upsetting their mechanics,parts suppliers etc..and because they read the first post about only reputable people to add to this discussion.
Im not saying you are not reputable Pete,but im saying =you do not have the problem and are not aware of the current problems race car people have with the current batch of available syncros,and engagement problems.
To the many racers that have the problem,,hopefully a solution will be found,and someone can be a ginny pig to try the solution.
I thought for a long time about addressing this problem here on the BB,but I need to find a solution.
A solution to a problem that many around the world do have.


Pete,,let me say something
In the many races I have done in 30 odd years,including 17= 6hr relay races,10-15 lappers,supersprints,building hundreds of customers gearboxes for road-race applications etc etc etc,,with the only problems being crunchy gears,so lets change the syncros n maybe a dog teeth or 2 and maybe a sliding hub,there has never been a failure.
To all the other Alfa specialists in Australia with the same problem,im voiceing the problem
Current syncros are a problem at the moment.
In the past 25 years or so,,SUITABLE gearbox oils ,were used with never a problem.
Now,it is recommended to use Redline 80-90NS,lucas oils etc etc,and the problem still exists.
The I was told to modify the new syncros to stop the problem.
Why dont they SUPPLY the SYNCROS modified ????????
Problem still exists.

To the MANY,,and I mean MANY people out there who have sent me private messages with the problem= Thank you.
To all the others,sitting on the side and waiting for a solution,a solution will be found.
Enough from me Pete,and please dont take it the wrong way.

Robert
 

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No problem Robert, and yes I know my comments were not addressing the current supply of synchro rings issue. Something if not sorted I will potentially strike as my synchros are rooted in my gearbox.

Good luck. I've never even heard of gearbox issues with 105 series race cars ... other than bellhousings breaking.
Pete
 

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All cool Pete.

Hurry up and finish that restoration,and more progress pictures

Robert
Garage is being extended at the moment. I have to take family on 2 week holiday first :eek:, but will be pooring concrete as soon as I can afterwards. Garage extension should be completed by Christmas, thus I can get all 'her' parts under the same roof making trial assembly much easier. Should have one side of the car 100% complete and etch primed around the same time, or not much later.
Pete
ps: I also have to renovate laundary ... part of the shed extension deal, but that shouldn't take long.
 

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First off I'm not a racer (officially) and I hope this is relevant, if not please ignore. Two Alfas, both 74's a spider and GTV. I rebuilt the spider box with syncros from a supplier in the UK. It shifts perfectly and precise, the syncro really grabs that sleeve. The gtv box was built with a new second gear and syncros and sleeves from a US supplier. The differences between the two are night and day. The GTV felt like shifting peanut butter. I recently took that box apart and put in two new rings and sleeve for 1&2. The difference is amazing it now shifts like the spider and in looking at the UK supplies rings they definitly had more meat on them and the surface was also more like a 320 grit whereas the US rings were more like a 400. I even thanked Max for supplying such a good product. Don't know if that adds anything positive, hope it does.
 

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Discussion Starter #37
Hi Gigem75

Sounds positive for road cars,,but not race cars.
And thanks to the off line Pms from others around the world with problems.
It will hopefully get sorted soon.
Those second hand yellow banded syncro rings are gold at the moment.

Robert
 

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Richard Jemison
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Syncro internals

The internals of the syncro assemblies must be matched to the size of the syncro receiver (dog tooth unit that is pressed on the gear).

There are two sizes, smaller splined diameter and larger spline diameter used on late model boxes.

The smaller early ones have wider internal spacing and require the thicker locating lock & internal slider.

Pics show differences, and I`m only showing the 4 internal parts from the
2nd - 5th syncro parts as the ist gear type is different. (3 different internal designs all with poor engagement vices)

The 1st gear syncro reciever can be converted with the 4 internal parts. Extra slot in the receiver isn`t an issue as long as teeth are usable.

Note thickness difference. Using incorrect one can cause total destruction of syncro, or at best no syncro action.

Pic is of early (small) receiver with correct parts in it and internal lock and slider for the later larger receiver laying next to them.
 

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Stiff Syncros

A Alfa friend from Louisville brought me his transmission for his Guilia a few weeks ago. He had it rebuilt by a mechanic in Louisville, replacing the syncros on second gear and installing new oil seals. When the friend reinstalled the gear box in the car, it would not go into third gear. Thus he came to me. I've done a bunch and have given a lot of lessons on switching syncros, replacing dogs etc.

We spent a Saturday afternoon in the workshop tearing his gearbox back apart. The Louisville mechanic has installed a new syncro on third gear (third gear is easiest to do because it's on the end of the main shaft.) Appearently the guy in Louisville doesn't know one gear from another in an Alfa box or maybe he can't count. I don't know.

Anyway, we took the syncro off and comparied it to others I have kept from previous rebuids.

The new ring was a lot rougher and alot stiffer. You could not push a sycro- sleeve over the syncronizing ring - by hand. Tried some other gears with old syncronizers on them. You can easily push the sleeve over the ring.

Our final deduction. "The new rings from U.S. suppliers are way too rough and way to stiff." Somebody has got to do something about this.

I just offer this if you are considering rebuilding your gearbox. I suggest trying to source new syncronizer rings from Europe. Maybe a German supplier. Good Luck.
 

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i know this is about stock( ish ) alfa trannys, but after a while,, there will be no more stock of these parts. gutting gearboxes, is just like stealing form peter to pay paul.. at some point in the near future.. this will be a costly problem..most of you know by now i have a w/c t5 in my car.. very cheap and easy to get all the parts for my tranny, and i can shift it as fast as i want..got a sticker shock, when i saw the prices for just the bearings for the stock alfa tranny( I.A.P. catolog), so i decided to go a diff. direction, very happy with myset up...even my freind whom drivin my spider love the way it shifts.. from 1 st gear to 5th and back down.... i really hope that one of our supplers, bite the coming bulit, and have someone make the dog gears and synco's for later drivers.must keep these cars on the road.
 
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