assembly questions

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ChargerST

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I'm assembling the mainshaft and realized that I can spin first and second gear but not third gear. Turns out that the synchronizer hub (3-4 synchro) rubs against the front of the third gear cone once I put the snap ring in place and prevents the gear from turning freely.
How much clearance should I have there?

All snap rings I have are the same thickness..

Should I try to grind down the hub or front of gear cone or file the snap ring a bit to get a few thousands clearance?

Here's a pic (you can see that the front of the gear cone has touched the synchro hub as the black coating was rubbed off). Synchro shows the side that is oriented towards third gear.

Or should I just run it and the gears will wear in?

20220126_210349.jpg


Another question: am I missing a wire ring in my input shaft (there is one in place but should there be a second one further down as there is a groove)? Or a washer? The rollers are way loose (lots of fore/after movement) or am I using the wrong rollers (see pic - I think the shorter ones are correct - longer ones don't fit - they are from the cluster gear)?
I have Passon's A833 book and it only mentions that the snap ring needs to be in place...


20220126_202459.jpg


20220126_202510.jpg
 
ChargerST said:
I'm assembling the mainshaft and realized that I can spin first and second gear but not third gear. Turns out that the synchronizer hub (3-4 synchro) rubs against the front of the third gear cone once I put the snap ring in place and prevents the gear from turning freely.
How much clearance should I have there?

All snap rings I have are the same thickness..

Should I try to grind down the hub or front of gear cone or file the snap ring a bit to get a few thousands clearance?

Here's a pic (you can see that the front of the gear cone has touched the synchro hub as the black coating was rubbed off). Synchro shows the side that is oriented towards third gear.

Or should I just run it and the gears will wear in?

View attachment 1715859424

Another question: am I missing a wire ring in my input shaft (there is one in place but should there be a second one further down as there is a groove)? Or a washer? The rollers are way loose (lots of fore/after movement) or am I using the wrong rollers (see pic - I think the shorter ones are correct - longer ones don't fit - they are from the cluster gear)?
I have Passon's A833 book and it only mentions that the snap ring needs to be in place...


View attachment 1715859426

View attachment 1715859427
Click to expand...


Just the one snap ring in the input.

Can you take another picture of the 3-4 slider?
 
Ok, so it's ok that the rollers can move back an forth?

Do you mean a picture of the hub? Or the slider?

Here is a closer picture of third gear and one of the synchro assembly from the other side. Will take more pictures tomorrow.

20220126_210358.jpg


20220126_210335.jpg
 
The rollers are fine they have always been shorter than the raceway

But your complete 3-4 synchronizer assembly does not look A833 to me.,
and most of all, your third gear overhangs the hub-stop on the mainshaft, that's not right either.
I don't know what's going on there, and I have built dozens of A833s and hundreds of Manual transmissions in general. I'll let my brain sizzle on it for a while, and see what what drops out.
I'd like to see an edge view of the slider, and
one of the thrust flange part of the mainshaft. I have seen pieces of those flanges broken off , and poorly welded back together.
 
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Compared it to another mainshaft and dimensions are the same. Tried another 3rd gear from a 2.66 set (mine is a 3.09 set) and I get the same overhang - on both shafts! So I think this might be correct.
The synchro assembly is a late style torq lock synchro. Definitely A833 and hub/drum length is the same as on a different synchro I have...

Will get some pictures and numbers later tonight.
 
Well there are only three choices.........
and you can't know which one to cut until after you completely assemble the unit less the cover.
Then you will center the slider on the hub, and compare the distances from the slider to the clutch teeth on both sides; to the third gear versus to the fourth. But this will only give you a hint.
You gotta then, install the cover, and see where the fork lands, in neutral.
If it pulls the slider to the rear, then you can machine off the backside of the hub.
If it pulls the slider towards the front (fourth ) then something else is also wrong.

Here's a clue; the A230 hub fits on the A833shaft, but I remember once test-fitting it, only to discover I couldn't use it. But that was 40 years ago and I have forgotten what about it, made that so.
The sliders are hub-specific. But those, the factory made obviously different. Your pics should clue my old brain in.
My guess is that you have an A230 hub there or A230 synchronizer; which is why I asked for the slider pic.
Meanwhile; IIRC I have a box of A833 parts kicking around somewhere, with hubs in it. I'll see if I can find the box and measure the hub depth, then report back;
But the results will not be posted today.
In the meanwhile, if you care to measure your 1-2 hub, IIRC both hubs have the same depth in the splined area.
 
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Thanks AJ! Hubs are 3-4 ones - no doubt as they are quite different than the 1-2 hubs. The depth (just the splined part that sits on the mainshaft) is exactly 20.00mm = 0.7874"
I only need a few thousands clearance so I don't think it matters where I take it off.
oh, the 3-4 synchro assembly is NOT a torq lock one (I use that type for the 1-2 synchro) but will post some pictures later.
 
took the synchro assembly apart. Hub is on the left (right hub is from another 3-4 assembly for comparison) and it measures almost the same as the other one (difference in hub thickness is only 0.002").

What is interesting is that first and second gear have much more clearance (I can move the gears 0.01"-0.02" on the shaft back and forth). Third has no meaningful clearance independent of which hub I use.

20220127_170022.jpg


20220127_165939.jpg
 
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I am almost 100% sure ;
>That slider is NOT an A833.
>That slider is an A230
>That Neither of those front hubs are A833

Hang on; we'll get a second opinion.
@CudaFactHackJob , what say you?
anyone else?

I have used the A230 slider in an A833 so I know it works.
But like in a previous post, I was unsuccessful in using the A230 hub. Since I had a boxfull of hubs I just used the proper one.
 
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AJ/FormS said:
I am almost 100% sure ;
>That slider is NOT an A833.
>That slider is an A230
>That Neither of those front hubs are A833

Hang on; we'll get a second opinion.
@CudaFactHackJob , what say you?
anyone else?

I have used the A230 slider in an A833 so I know it works.
But like in a previous post, I was unsuccessful in using the A230 hub. Since I had a boxfull of hubs I just used the proper one.
Click to expand...

Could you measure one hub for me? I might have another one but need to find it first...

The hub + 3rd gear stacked together on the bench has a height of 66.70mm (2.626") - see pic.
Distance between shoulder on mainshaft and snap ring groove is 66.10mm (2.603").
Snap ring groove is 2.70mm wide and snap ring 2.20mm giving me 0.50mm play in the groove - but I need 0.60mm (66.70 - 66.10 = 0.60)

That means I need to gain 0.10mm clearance minimum.

20220127_204437.jpg


20220127_204411.jpg
 
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Ok I found my A833 stuff
Hubs are;
early style; 20mm and 29.3 across the slider ways
late style; 25mm and 31.8 A/A
overdrive; 20mm and 31.9 A/A
Gear is 41.65mm, Edit;See below
ok I messed up; it turns out that 41.65 is Second gear and I have no spare third gears.Nor do I have a shaft to check.
My apologies.
please refresh your screen
 
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I got several overdrive shafts, I wonder what they measure at. Back in a bit.

Ok I think we need to choose a different reference point.
On these three o/d shafts, the snap-ring groove varies in width by quite a bit (up to .4 mm), But they all have a common measurement from shoulder to the front-most edge of the groove, which is 69.0mm or a hair under; on these three.
By your math, yours are;
66.1 + 2.7= 68.8 which is dang close to 69.0
Johndees measures 2.61=66.3 adding 2.7 for the groove makes his 69.0, or a tic under.
By preponderance of evidence then, a tic under 69.0 (2.71inch) looks to be correct.
I think maybe you just need a thinner snapring? I think they are select fit, but I do not know the range of thicknesses available. The 1969 FSM is no help. You would need a parts manual.

You say your front snap ring is 2.2mm That seems awful thick to my memory. Lemmee go measure a couple of mine. Be right back. Nope, mine are all at 2.2 as well.
your stack-up is;
66.7 (2.626), plus the 2.2 snapring is 68.9 right? and all the shafts measure a tic under 69mm (2.716), which by the math is .1mm=about .003 TO SPARE .....
By any chance is your snap-ring bent? or twisted?
I mean .003 is probably tighter than I'd like to see, but it should be enough to NOT be jammed up. If I was building it, I'd want about .007 to .015 between the shoulder and the third-gear with the gear pressed forward. Again the FSM doesn't say.
The only spec in my FSM is .015 to .030 on the cluster.
So IDK. If you have to cut something, I would chose the hub on account of the gear is extremely hard.

Happy HotRodding ...... lol
 
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Thanks for all the measurements and thank you @johndee aa well! I'll do another close up inspection on the groove, should, hub, snap ring - f I can't find anything I'll remove 0.15mm from the hub and call it a day!
 
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