Alfa Romeo Forums banner

1 - 20 of 23 Posts

·
Registered
Joined
·
145 Posts
Discussion Starter #1
The second gear grind has finally driven me over the edge. How much is it going to cost me to have the gear box rebuilt? I dream of a smooth in and out of second gear!
 

·
Registered
Joined
·
4,306 Posts
I rebuilt my transmission about 10 years ago and the only parts I replaced were the synchro rings. It has been working flawlessly ever since and now has a total of over 380,000 miles on it. So parts-wise you're probably not looking at much. I did the rework myself and it really wasn't that tough of a job but I had entire engine/tranny out for complete rebuild anyway.
 

·
Registered
Joined
·
264 Posts
I just double clutch.....
+1 ^^^^

When I bought my 88 Grad I assumed that the tranny was toast and that a complete rebuild would be required before the car would be roadworthy.

I felt the deal was worth it (in retrospect that was foolish, but...)

When I got the car home I found that there was about 1/2 cup of a tar like substance that used to be gear oil in the transmission. I filled and drained it about 4 times within 100 miles of driving and each time it got better. Finally, after the oil came out looking like oil I put in the Redline NS that is often recommended on this board.

The transmission is now "serviceable" in that it can be driven if properly double clutched. I've gotten pretty good at it, and I don't really think much about it anymore, it's become habit.

I wouldn't even consider tearing into it at this point. If I had to put in a clutch I would probably address the syncro issue, but until then I'm perfectly content to double clutch for a long time.
 

·
Registered
Joined
·
705 Posts
I rebuilt my transmission about 10 years ago and the only parts I replaced were the synchro rings. It has been working flawlessly ever since and now has a total of over 380,000 miles on it. So parts-wise you're probably not looking at much. I did the rework myself and it really wasn't that tough of a job but I had entire engine/tranny out for complete rebuild anyway.
Paul, you really need to do a full disclosure thingy here. I mean, you're an aircraft mechanic, right? Transmission rebuilds are um...complicated, aren't they?
 

·
Registered
Joined
·
2,045 Posts
My 2 88's both had/have the 2nd gear grind downshift problem. I bought a supposedly rebuilt transmission with new syncros off another BB member who had sold his car before installing the rebuilt unit. I have had the rebuilt in the basement for 4 years and will eventually install it when a clutch issue forces me to go through the agony of a transmission R & R. But I learned to double clutch successfully enough that for now I would rather double clutch than R & R the gearbox to install what is supposedly a rebuilt unit but is actually an unknown transmission. My worse fear is that I install the rebuilt unit and discover that it is not what it was proported to be. Worse case situation is that the new unit turns out to be a box of rocks.

Robert
 

·
Registered
Joined
·
4,306 Posts
Paul, you really need to do a full disclosure thingy here. I mean, you're an aircraft mechanic, right? Transmission rebuilds are um...complicated, aren't they?
I'll disclose that I was intimidated but it really wasn't as bad as I had imagined. The parts diagram is very detailed and honestly it is nearly impossible to reassemble it wrong because it just won't go back together if anything is out of place. That and you obviously shouldn't have any parts left over when you're done :whistling:

But my real point was that it is most likely very few new parts will be required. My gears and all my bearings were just fine. There is even a procedure spelled out somewhere describing how you can flip and swap the synchro rings and avoid having to even buy them.

I didn't mean to make it sound like a walk in the park though, certainly you need to have some mechanical aptitude.
 

·
Registered
Joined
·
2,045 Posts
I'll disclose that I was intimidated but it really wasn't as bad as I had imagined. The parts diagram is very detailed and honestly it is nearly impossible to reassemble it wrong because it just won't go back together if anything is out of place. That and you obviously shouldn't have any parts left over when you're done :whistling:

But my real point was that it is most likely very few new parts will be required. My gears and all my bearings were just fine. There is even a procedure spelled out somewhere describing how you can flip and swap the synchro rings and avoid having to even buy them.

I didn't mean to make it sound like a walk in the park though, certainly you need to have some mechanical aptitude.
But didn't you need a gear press to do the job? I have only been into a few Alfa gearboxes, but I always had to use a press to get the main shaft apart and back together again.

Robert
 

·
Registered
Joined
·
557 Posts
vf31rhill - I am in a similar situation, but I think this winter I am going to pull my tranny and put in my "good one". For me if I shift into 1st too quickly or also 3rd I get some crunching, so I figured I'll do the switch and then try my hand at rebuilding my old box if the "new" one isn't what it was billed to be. If I have to I figure I can rebuild the old box and put it back in before spring either way.
I guess this still doesn't answer PJN's original question....sorry.
 

·
Registered
Joined
·
2,045 Posts
vf31rhill - I am in a similar situation, but I think this winter I am going to pull my tranny and put in my "good one". For me if I shift into 1st too quickly or also 3rd I get some crunching, so I figured I'll do the switch and then try my hand at rebuilding my old box if the "new" one isn't what it was billed to be
Yes, an unknown Alfa transmission install is a bit of a crap shoot. I currently have 5 extra transmissions including the "rebuilt" but am afraid to install any of them without disassembleing and inspecting them first. And if you are going to do all that work, might as well just rebuild the thing in the process. I wrenched on BMCs for 17 years and rebuilt literly hundreds of their cranky old gearboxes. All of them were pretty poor except for the late big shaft MGBs. But at least they had that lovely inspection plate on the side (or top as with the Standard Triumph) which allowed a quick look inside without having to split the case - as is the case with these Alfa 4 and 5 speeds.

Robert
 

·
Registered
Joined
·
398 Posts
I have a spare motor and tranny which I intend to rebuild over the next couple of years or so. Just need to get my heated garage built first.

In the mean time I just say to myself that the fun begins after the crunch! :thumbup:
 

·
Registered
Joined
·
7,710 Posts
It can be done without a press.. There are some tools you will need though that are not common...A) BBQ Grille or toaster oven B) A very good pair of large snap ring pliers ( you will know why) C) a large box end wrench , large enough to slip over the shaft D) a clear bench with an eye for detail.

If you don't change out the gears, a sense of the order of the shims that usually stick to gears in the oil residue is important.

Flipping synchros on a 101 was common as the synchros are grooved and relatively easy to read for wear. Taking the 5th gear synchro and flipping it into the 2nd gear hub was a "simple" procedure with the worn 2nd going into the 5th. If 2nd is really really worn, that can be risky. On 105's I wouldn't bother and put all new ones in for peace of mind.

The BBQ heats up the pressed on pieces to about 200-250F and they will slide into place with a good final thwack if you don't work fast enough.

As was said, not recommended if your mechanical aptitude is limited to oil changes and tire rotation and you don't have a manual other than a parts manual.
 

·
Registered
Joined
·
2,045 Posts
Flipping synchros on a 101 was common as the synchros are grooved and relatively easy to read for wear. Taking the 5th gear synchro and flipping it into the 2nd gear hub was a "simple" procedure with the worn 2nd going into the 5th. If 2nd is really really worn, that can be risky. On 105's I wouldn't bother and put all new ones in for peace of mind
Since you seem knowledgeable on these Alfa gearboxes, what is with these moly syncro hubs and moly syncro rings they advertise in the IAP catalogue? Are these something new and are they what you would recommend for syncro replacement in a 105 gearbox? When you speak of putting in all new ones, are you refering to hub/ring pairs? If you were going through a 105 gearbox with all good gearsets and bearings, exactly what would you replace as a matter of course besides front and rear seals?

Thanks in advance, Robert
 

·
Registered
Joined
·
7,710 Posts
Since you seem knowledgeable on these Alfa gearboxes, what is with these moly syncro hubs and moly syncro rings they advertise in the IAP catalogue? Are these something new and are they what you would recommend for syncro replacement in a 105 gearbox? When you speak of putting in all new ones, are you refering to hub/ring pairs? If you were going through a 105 gearbox with all good gearsets and bearings, exactly what would you replace as a matter of course besides front and rear seals?

Thanks in advance, Robert
The 101 rings and sliding sleeves are specific to the early gearboxes that required Dentax or straight 90 W oil to work properly and not wear prematurely. These wore prematurely because independent shops in the day would not adhere to this oil recommendation and use common multi-weight gear oil which led to grouchy gears and owners and a change in the design and materials. If the dogs won't do as you say, you adapt to the dog. These 101 parts became obsolete and the 105's on started coming with new designs which were more compliant with multi-grade oils. The new 105 type rings have a pebbly surface design as opposed to groove and are called "moly" type rings. The sleeves and rings should not be mixed from 101 to 105 and measuring wear on the sleeves is something only an expert like Alfa7 can do by eye.

If you are working on a 105 or later gear box, it just makes sense to replace all the rings and sleeves and not swap out stuff that is readily available. Purists, I'm not a purist but believe this to be true, believe the 101 box is a smidgeon smoother that a 105. In the end, the new moly rings and sleeves are the best way to go for just the satisfaction that it works. The hubs are good forever, the part the sleeve slides on with the three legs. Bearings are your choice but I have never changed them if the thing hasn't been run bone dry. I have never had to mess with anything on the layshaft. Gears like #2 can get a little testy but unless the small engaging teeth are completely rounded off to a nub caused by clashing they should be fine. I've seen some broken off, one or two but it will be fine.
 

·
Richard Jemison
Joined
·
7,376 Posts
Trans rebuild

what is with these moly syncro hubs and moly syncro rings they advertise in the IAP catalogue? Are these something new and are they what you would recommend for syncro replacement in a 105 gearbox? When you speak of putting in all new ones, are you refering to hub/ring pairs? If you were going through a 105 gearbox with all good gearsets and bearings, exactly what would you replace as a matter of course besides front and rear seals?
These are not the same quality as the original as are any of them advertised as "New OE Syncros)
If you are going to put in a Alfa transmission that has not been refreshed, pay attention to the work and proceedures involved in the R&R process as you will be re-doing the same thing the next week. They all develop the same issues, due to design and lubricants used by the factory.

If you plan to pull one apart have:
-Front and rear seals,
-Small needle bearing that fits in 4th gear (new)
-2 complete donor 4th or 5th gear syncro assemblies (complete reciever/with band and internal brake parts, and slider ring from a 5th gear donor. These will replace the one directional syncro on 1st gear and the worn one on 2nd gear.
-If a pre 1974 box have a NEW output shaft bearing & race.

Check the wear in the shift forks. If slider is loose in it replace the shift fork.

That`s the basics, 3rd gear might need a syncro band or assembly if teeth are worn.

Donor parts can be had from Larry at APE. However he Pi$$es and moans about selling complete 4th/5th syncro assemblies as he uses them in his rebuilt transmissions they sell.

I keep a pair of lightened 1st and second gears with 4th gear syncros and 5th slider ring boxed for just such projects. See pic. This one set has a 5th/rev lightened gear and seals for the post `69 bellhousing and rear.

Don`t build a trans without using Redline 75-90 NS after assembly!
 

Attachments

·
Registered
Joined
·
7,710 Posts
These are not the same quality as the original as are any of them advertised as "New OE Syncros)
If you are going to put in a Alfa transmission that has not been refreshed, pay attention to the work and proceedures involved in the R&R process as you will be re-doing the same thing the next week. They all develop the same issues, due to design and lubricants used by the factory.

If you plan to pull one apart have:
-Front and rear seals,
-Small needle bearing that fits in 4th gear (new)
-2 complete donor 4th or 5th gear syncro assemblies (complete reciever/with band and internal brake parts, and slider ring from a 5th gear donor. These will replace the one directional syncro on 1st gear and the worn one on 2nd gear.
-If a pre 1974 box have a NEW output shaft bearing & race.

Check the wear in the shift forks. If slider is loose in it replace the shift fork.

That`s the basics, 3rd gear might need a syncro band or assembly if teeth are worn.

Donor parts can be had from Larry at APE. However he Pi$$es and moans about selling complete 4th/5th syncro assemblies as he uses them in his rebuilt transmissions they sell.

I keep a pair of lightened 1st and second gears with 4th gear syncros and 5th slider ring boxed for just such projects.

Don`t build a trans without using Redline 75-90 NS after assembly!
I concur with the shift forks thing. Sorry I overlooked that. If they are worn or galled, They should be replaced. Some of the manuals show pictures, like Autobooks. and Redline is great stuff too for 105's for sure. Thanks Richard.
 
1 - 20 of 23 Posts
Top