Reverse gear failures

Steve Hoelscher said:
Wow, that video makes me cringe. :eek: Clearly the driver isn't the one who will be making the repairs. ;)



Well, I am currently building these transmissions for $1750, plush shipping and a $350 core charge (assuming the core is usable it is refunded). This is given the current parts availability

If I make some assumptions about the job I can give you a range of pricing. Assuming to drop the car off at a shop that actually knows something about X1/9s and is competent to do the work; R&R (remove and re-install) labor can run $800~$1000+ depending on the local economy (obviously labor rates vary from places like major California cities to a small town with a low cost of living). Assuming that shop also did the rebuild figure $1000+ in parts, plus labor at $500~$1000. I would think that a reasonable rate for the job would be $2500 to $3500 depending on the parts needed and the local overhead. Parts costs could easily run the price up if the transmission needed more parts than just reverse and I am betting it will. That's pretty much the way I would price it out to a customer and while it that number sounds really high it is legit.

These days I would expect that most shops would either reject the job or price it very high to make sure they cover their butt's if the customer says yes and they find themselves in over their heads. I have bailed out a few shops over the years that found themselves unable to find parts or fix a problem and had to send me the unit to fix.
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Thanks, honestly I am debating keeping this car, It kills me so bad this happened. But it did, I'm in the Detroit area, You dont happen to know any shops or people here you could recommend? The guy/shop that worked in this prior to this incident happening has retired/closed.
 
Might also be worth mentioning that engaging first gear when car is moving forward at any speed puts wear on reverse idler teeth, as well as 1-2 slider teeth...
I don't engage first gear at any speed greater than 1 mph...

Is this good, Steve?
 
"C snapp" brings up a good point. Back when I was taught to use a manual transmission, all trans units were of a similar design to the Fiat's (that's the era when I learned to drive a stick). Many did not have any type of syncro on first gear. And I was told to never use 1st gear as anything other than to get the vehicle started moving from a stop. Also not to try to engage 1st until the vehicle completely stopped moving. My teacher (dad) owned a chain of transmission repair shops prior to that, so I trusted his knowledge. I know these days many trans are designed differently, such as having some type of syncro on 1st. And I'm sure it is common to use 1st as a gear during racing, etc., but I still believe the best policy on an older vehicle, for street use, is to NOT consider 1st as a gear beyond initial movement. Frankly it is too low for practical use beyond that anyway (in my opinion).
 
First gear in a 128 derivative box is synchronized... it's just that engaging first gear also engages reverse idler in its rest position, which does wear reverse teeth on said idler and 1-2 slider.
 
Ya, I was just saying there were a lot of trans that did not have 1st gear syncros back then. I know, that was a long time ago. :)

Another suggestion I was told was to engage 3rd first, then 1st, when at a stop. The idea was to stop all components from spinning with 3rd gear first. But that primarily went along with those designs that had no 1st gear syncro.
 
c snapp said:
Might also be worth mentioning that engaging first gear when car is moving forward at any speed puts wear on reverse idler teeth, as well as 1-2 slider teeth...
I don't engage first gear at any speed greater than 1 mph...

Is this good, Steve?
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Yes. Its typically not necessary to downshift to 1st when moving anyway. If the car is rolling, 2nd is probably adequate.

Thought I would add a couple of photos to the thread. Since my original post I have torn down two cores that were returned from customers. Both were being replaced because of a number of issues but both had inoperable reverses. The two photos are of the two reverse idler gears. Sadly, neither is that unusual.


0517181332.jpg



0517181332b.jpg
 
More reverse fun. I tore down a core last week that I was told had no issues with reverse. This unit had been rebuilt by a previous owner of the car and was working "reasonably well" as described by the current owner. I honestly never know what I am going to find when I tear a unit down. I have often said I have seen it all and can't be surprised any more and then I found this:

End Cap Off.jpg


Both Nuts.jpg


If the orange RTV around the main gasket didn't tell me somebody had been into this unit, once I had the end cap off it was rather obvious. In case you are not sure of what you are looking at, the end nuts were installed using a chisel. No kidding. And the bevel washer on the end was installed upside down. So not only was there insufficient torque on the retaining nut but the bevel washer couldn't add it preload to the gearset.

Bevel Washer.jpg


But wait, there's more....

The PO had replaced a lot of parts; 1-2 slider, reverse idler gear, 3-4 slider, 3rd gear, etc... but he re-used an input shaft that had a pretty chewed up reverse gear. So the chewed up reverse gear chewed up the idler. Ultimately, it would have stripped reverse. Also, the inadequate preload on the gear stack probably also contributed to the engagement side of the reverse idler gear getting chewed up along with the engagement side of the 1-2 slider.

This _was_ a fairly new reverse idler:

Reverse Edge On.jpg


Reverse Worn B.jpg


Reverse Worn A.jpg



While its hard to see the reverse gear teeth are worn badly and deformed. These were probably like this when the previous rebuild was done.

Reverse Input.jpg


The transmission had a few other problems. The diff bearings were replaced but the rebuilder didn't reshim the preload. So they appear to have been run with far too little preload. So the bearing are toast.

Sadly, the 3-4 slider, which appeared to be new from the rebuild, was worn out, as well as 3rd gear, and 4th wasn't great. This probably due to the insufficient preload to the gearset.

Again, this transmission "worked reasonably well". I have no doubt, but it was a time bomb set by the previous rebuilder.
 
Hey gang that was MY transmission and it actually did seem to work well. Didn't leak when I acquired it but after swapping std gear oil with MTL it had a small drip. ...and 3rd gear syncros were tired. Never had any problems with 1st, reverse, etc. I was planning to rebuild it myself someday, but when Steve began offering rebuilds I thought it might be more wise to let a pro handle it.

Wow -- I certainly am glad I did. From Steve's description the PO did a poor rebuild job on this one and while it seemed OK to me it sounds like it was going to fail sooner rather than later.
 
Now I'm really curious to tear into the non-op trans I have sitting on the bench, just to see what wonderfulness lies beneath. How exciting, like Christmas wondering what I'll get this year!
 
Dr.Jeff said:
Now I'm really curious to tear into the non-op trans I have sitting on the bench, just to see what wonderfulness lies beneath. How exciting, like Christmas wondering what I'll get this year!
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That right there is surly the signs of a sick mind... LOL
But I do the same thing...
 
Staking? I had already 'un-staked'the nuts when I too the photo with the end cap off. I shouldn't have because I don't think I have ever seen more thoroughly staked nuts. The correct procedure is to simply dimple the nut with a punch or chisel. These had an entire section of the nut's sleeve driven fully into the slot on the shaft. Perhaps the rebuilder knew he wasn't doing a proper job of torquing the nuts and tried to supplement torque with the maximum staking?

Like many of us, I have worked on dozens of X1/9s over the years and frequently have to shake my head at the dumb stuff that I find as evidence of previous attempts at service. Often, considerable effort went into "doing it wrong". X1/9 transmissions are often the best "worst" example because of the lack of transmission knowledge in general. I am probably as guilty as any in my early attempts at transmission repair. I knew virtually nothing when I tried to fix my first X1/9's broke transmission. Happily, it seemed to work fine until I went to put it in reverse to back out of the garage and it took off forward, in 2nd gear. :(

More pic's of Greg's core: The tail-tells of poor workmanshift: Heavy use of the wrong RTV (orange).

Open.jpg


First evidence of reverse problems. Note lots of metal shards on the magnet (lower right corner of the photo).

Reverse Idler.jpg


I took a pic of the residual oil that came out after disassembly to show the sheen of residual metal but it didn't turn out in the photo.
 
Steve Hoelscher said:
More reverse fun. I tore down a core last week that I was told had no issues with reverse. This unit had been rebuilt by a previous owner of the car and was working "reasonably well" as described by the current owner. I honestly never know what I am going to find when I tear a unit down. I have often said I have seen it all and can't be surprised any more and then I found this:

View attachment 11683

View attachment 11687

If the orange RTV around the main gasket didn't tell me somebody had been into this unit, once I had the end cap off it was rather obvious. In case you are not sure of what you are looking at, the end nuts were installed using a chisel. No kidding. And the bevel washer on the end was installed upside down. So not only was there insufficient torque on the retaining nut but the bevel washer couldn't add it preload to the gearset.

View attachment 11684

But wait, there's more....

The PO had replaced a lot of parts; 1-2 slider, reverse idler gear, 3-4 slider, 3rd gear, etc... but he re-used an input shaft that had a pretty chewed up reverse gear. So the chewed up reverse gear chewed up the idler. Ultimately, it would have stripped reverse. Also, the inadequate preload on the gear stack probably also contributed to the engagement side of the reverse idler gear getting chewed up along with the engagement side of the 1-2 slider.

This _was_ a fairly new reverse idler:

View attachment 11685

View attachment 11686

View attachment 11691


While its hard to see the reverse gear teeth are worn badly and deformed. These were probably like this when the previous rebuild was done.

View attachment 11688

The transmission had a few other problems. The diff bearings were replaced but the rebuilder didn't reshim the preload. So they appear to have been run with far too little preload. So the bearing are toast.

Sadly, the 3-4 slider, which appeared to be new from the rebuild, was worn out, as well as 3rd gear, and 4th wasn't great. This probably due to the insufficient preload to the gearset.

Again, this transmission "worked reasonably well". I have no doubt, but it was a time bomb set by the previous rebuilder.
Click to expand...

This reminded me of one I rebuild for a customer a couple months back.

IMG_20170512_154716276.jpg


Customer stated... " Cant shift into 5th gear"
 
Steve, you know I was joking about the 'staked' nuts. :)

O.K., so for the rest of us uninformed types, what are we seeing in the last pic from Brayden (aside from heavily staked nuts)? Something there kept it from going into 5th? Perhaps I'm missing the obvious.
 
Dr.Jeff said:
What caused this grove?

View attachment 11703
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Whoever rebuilt the transmission before I did put the whole slider assembly on upside down. The groves are for oiling 5th and are supposed to be facing down with the washer on top.

Instead they put the washer directly on top of 5th and sandwiched it under that piece like so..


IMG_20170512_155218504.jpg
IMG_20170512_154807685.jpg


Another issue I found on that transmission was "slightly" excessive sealant... AND A BONUS SPRING!!

IMG_20170512_161341436.jpg
 
I saw that the 5th slider hub was on upside down. I have't tried to assemble one like that so I am not sure what would cause it to "not go into 5th" but there are a whole list of bad results from that.

Not to mention its full of rust.

Re: the excessive RTV Brandon noted. That seems to foretell a lot of surprises once you get inside. The excessive and incorrect RTV demonstrating the builder's lack of knowledge and skill.

I could do a whole thread on Detent Springs. :)
 
Dr.Jeff said:
Steve, you know I was joking about the 'staked' nuts. :)
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Yep.

When the cap first came off, for a moment, I wasn't sure what I was looking at. Then it struck me....

I was actually expecting much worse than I found. And this was thought to be the better of the two transmission's Greg had.
 
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