Dave WM

ZH I would like to try that bunged up 3rd you have, I could at least confirm its the gear for sure that way. If I get the exact same noise then I could assume its the 3rd counter shaft an not the output shaft gear. I hope to get it under the mag glass today to get a much closer look. I am going to mark the counter shaft where the noise occurs as well. If another gear results in the noise at that same spot on the CS gear, then it would follow the CS gear is bad. I am going to start by spraying some carb cleaner right at the spot I think the issue is, that way I can get a better look without any residual oil hiding any defect. I can tell you from a cursory look its not obvious.

here is the latest, I can engage 3rd gear and the bump sound takes places on the output shaft in exactly the same place every rotation (rear housing off bell on). I have examined the teeth of the 3rd and the counter shaft 3rd, can see nothing. the bump does NOT take place on the staked nut every rotation on the other gears engaged (moves around faster or slower on staked nut). The problem is when the case is off I get no bump even from 3rd. maybe the gears are not tightly meshed with out the cases, enough to mask a problem with 3rd (assuming that is it). as to bent shafts, the main shaft can be held still and it still bumps, so that should clear that one. the input shaft does not have single rotation bump, the only constant that relates time wise to the bump is an engaged 3rd gear. I can't see how the counter shaft could be bent. I presume if its the gear then it would be a single tooth so I have to mark the exact mesh point and get a much closer look. I was thinking the sliders but if they were the problem then the bump would take place on the same point along the output shaft regardless of which gear. And when the 3rd gear was removed it did not bump. will take a closer look at the 3rd and the counter shaft (boy if that is f'd then its hopeless) tomorrow when I have better light. I may pop for a new 3rd if I can get one from japan, that you had looked to far gone (at lest the engagement teeth did). That is IF I can find damage on the gear.

just evened it up. Maybe it could be closed up all the way. Its running perfectly true now, but I still have the noise, not as bad as before but its there, going to have to play with it some more. its getting to the point where I am starting to be discouraged by it. It seems to only be there when the front bell housing is on. If I leave the rear housing on it gone. I must still have something not running true, and the bell housing amplifies it like a resonating horn. The problem is since I cant reproduce it with the bell on, I have to look with it off and see if I can find something that could make the problem. I am almost to the point of just installing it and taking for a test ride. It would take less time that constantly assemble and disassemble. I still have the other one that does not have any of the same kind of noise, so that one will be installed if the test ride is a failure.

I installed the 3rd gear and before putting on the sycro hub I checked with a dial indicator, very good, finished installing the hub, counter shaft gear and input shaft, test spin by hand, no perceivable wobble. Just have to reinstall the front bearings before I can put back in bell for testing. oops, forgot the input shaft bearing needs to be installed BEFORE installing the input shaft/counter shaft gear, duh... I think that is the most fiddly bit about this job juggling the input shaft, brass sync ring and pressing on the counter shaft front gear all a the same time. I think I can see why the village land guy installs the countershaft with the front gear already on, he just meshes the two shafts while inserting them both into the adapter plate at the same time, not the way the FSM shows it.

maybe the bevel edge of a bearing puller..

I was shocked at how little force it took to square up that gear gap. I have a carpeted (thin) garage (less likely to chip things that way) I work in, maybe I dropped it and hit just right to mess up the gap, I don't remember doing that but can't say for sure. anyway will know soon enough, I will have it back together tonight to see.

new interesting development. that gap as VERY easy to adj with the press, I just applied some light pressure from the press and it squeezed the gap to very consistent. I will re install and use a dial gauge to confirm how square it sits.

trying to load video

here is the same hand cranking WITH the gear, in the beginning of the video.

and another to compare with hand cranking

got it back together, NO 3rd, I think it sounds a lot better, could not pick up on that metallic clanking sound.

will let you know after I test run it with out the gear installed, if noise still there, then gear is not the problem. If it is the problem I will see if I can press mine and fix the gap issue 1st. I realize the probability is this is NOT the problem , but its down to a process of elimination, this being the easiest gear to get at and some observable defect makes it a good starting point. The only other thing I can think of if its not a gear would be a defect in a fork/slider interface, but I did not see anything like that. If the noise persist with the gear off, I will try removing the fork next on that slider.

28t cool owl!

pick of the gear, 3 inch OD of teeth

new video

just about got it back together sans 3rd gear. left the needle bearing on. so as long as I don't try to shift into 3rd I should be able to run it and see if the noise is gone. I am going to have to remove the rear housing to press that big counter shaft back on so will not get it done today but should be able to assemble all by COB tomorrow. Will post up a pic of 3rd soon. It does appear to be a press fit. Of course all this goes to the question of how could this be the problem as I cant see how it could have been bad from day one, but frankly I am out of options so may as well mess with it and see. IF it does prove to be the problem you can bet I will see if I can "straighten" it with the press, don't want to defore the cone so not sure how I would do it. Plus I am sure there is a real chance of shattering it. The issue is its such a small deviation that I would need to apply pressure to the high side, that seems like a recipe for disaster but not sure what else to do. Hope ZH can locate as a plan B if this goes wrong. Clearly I am not going to do any thing to the gear unless the noise is gone (and therefore cause by 3rd). I suppose the other parts could be a factor like the shift fork, but the noise going in sync with the high side of the gap on the gear makes me want to believe this could be it.

got to use my new tool. when pulling that counter shaft gear, I have a 20 ton 2 jaw puller and it needed it. I think removed the 1st time when the CS was completely out, and used the press to get it out. Since I did not disassemble it this time I had to pull the gear with the shaft installed. my wimply 3 jaw big puller seemed like it was reaching its safe limit (just did not like the feel of it). So out comes the big boy, must weigh 20 lbs easy, any way it and my 36" cresent wrench to turn it made quick work of pulling the gear

I did try it. when in 3rd gear it was the worst. Its not the syncro hub but the actual gear, there is a split between the helical gear teeth and the dogs that engage the syncro hub, that is where the wobble takes place. will post up a video to better demo later. So far I have pulled the front bearings, the counter shaft gear and the input shaft/4th gear. All I have left to do is pull the 3/4 syncro, the pin and fork that holds it and I should be able to get the 3rd gear out. I know its a lot of work, but I will then reassemble with no 3rd and try it all again (bellhousing on and all). "nuke it from orbit its the only way to know for sure". If that is the problem, I am hoping ZH can come to the rescue again, If not I will see about a new 3 from japan, hard to find and I hope I can find the right one. It may sound silly but I really really want to figure this out, regardless of cost, even though I have one that maybe fine. I guess its just my nature. if the noise is still there after all that, well I hate so say it but may be forced to throw in the towel, geez I hate that.

more progress. I pulled the bell off leaving the rear ext housing on, this makes for a much more stable platform to observe. What I found as an issue with 3rd gear there is a gear part and an engagement teeth part and a separation of about .3mm all the way around by design. the engagement part is what the cone that grabs the brass ring is part of. I assume its a pressed together assy. there is a clear wobble here, the .3 varies around by as much as .1 mm (have to measure more but it is obvious. I will have to time it with the sound but I think it relates. this may account for the seemingly moving sound when attempting to clock to the main or counter. what I think I am hearing it a slight grabbing of the brass ring as the cone wobbles. maybe my setup clearance it too tight but the wobble is not present on gear 2 which seem to have the same separation of gear and engagement teeth part. The gap there is constant. the good news is I think I can remove the 3rd gear pretty easy, just pull the counter shaft front bearing, clip and gear, along with the input shaft, then a clip/washer/syncro to get to the 3 gear. perhaps when I pressed on the hub for that 3/4 syncro I pressed to hard. this is where all that yak about different thickness c clips come into play. I modified my spin process to just use a manual socket to adapt to the front input shaft, eliminates the drill noise and I can precisely see the gaps mentioned. re measured, the gap in the gear to engagement teeth is .7mm to .3mm so total variance of .4 mm as it wobbles. I double checked the end play about .008 which is pretty much right in the middle of the end gap clearance. My plan to isolate this gear as the issue will be to remove it, and see if the noise goes away. I

link to quiet transmission.

I was concerned about using the drill as well, not knowing if that was valid test, but the second trans using the same setup had no hint of the noise. Not shown but I tried moving the coupling around (move drill while spinning pull push up down etc.) to see if I could influence the sound, no joy. On my next try I am going to try it with the rear housing still on vs just the plate in the vice. The rear housing has the rear bearings mounts for both the shafts (output and counter) fixed so that should help stabilize the shafts forward from the adapter plate. Then I will spin it again. Don't know if it will give any insights, but at least I can look more closely at the action and maybe see something, like a coupling sleeve/fork etc... I was very careful about the synchro assemblies, but will look carefull at them as well, at least as well as you can with them installed. Fork movement transmitted to the shift rods sounds like a possibility. I am trying to think of what could transmit so much sound into the bell housing.

Tried it with the front cover off no effect, with the bellhousing off I get a considerable vibration in both the output shaft and countershaft. Hard to keep everything aligned. I was pretty careful with bearing install.

test done hold main shaft (output shaft, not sure which to call it) still with a drive shaft inserted in the tail housing. NO effect on the noise so that means it must be something in the countershaft or input shaft I guess... the JY transmission was used to verify, no noise using the same setup (drill and rubber coupling hose). will post the two videos tonight.

well how about this as a test of bent main shaft, I just hold it still (have a drive shaft I can use to secure it) and spin the input (while in neutral of course the sound was there regardless of gear or netural)? that should clear the all the countershaft parts and the input shaft gears and bearings and shims. I don't think I ever did that (hold it still). If the main shaft is not turning then it cant add to the sound. Not a definitive test of bent main shaft but at least clear those other parts.

not really a ticking sound, more like a rubbing sound, seems loudest at the front of the housing.