That makes me excited!
CK5
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The Great Smaug
- Thread starter campfire
- Start date
Tore into the NV3500. Need to ID the inside bearings to get the right kit ordered.
I missed this detent plug, which kept the halves from separating.
After 3 or 4 rounds of blue wrench treatment I was able to pry it out using a specially modified 9/16" wrench.
Then, after removing the detent plunger and spring, the halves come apart easily.
Not sure whether I broke this race or if it was just a timely time to be rebuilding this tranny.
Shiny goodness.
And that's how far I got before I ran out of time. The mainshaft bearings are supposed to be either 30MM or 33MM in diameter. My harbor freight micrometer measured 1.40" on the front of the mainshaft. Which is 35.5MM.
So I'm gonna tear it further down tonight and get a more solid reading of those bearing sizes. I know it's HF junk, but I shouldn't be .100" off on that measurement. 
And, if I read this date code right, I have a Christmas Break edition of this NV3500. 12/20/99. 2000 model year should have the larger bearings. So that makes sense.
I missed this detent plug, which kept the halves from separating.
After 3 or 4 rounds of blue wrench treatment I was able to pry it out using a specially modified 9/16" wrench.
Then, after removing the detent plunger and spring, the halves come apart easily.
Not sure whether I broke this race or if it was just a timely time to be rebuilding this tranny.
Shiny goodness.
And that's how far I got before I ran out of time. The mainshaft bearings are supposed to be either 30MM or 33MM in diameter. My harbor freight micrometer measured 1.40" on the front of the mainshaft. Which is 35.5MM.
So I'm gonna tear it further down tonight and get a more solid reading of those bearing sizes. I know it's HF junk, but I shouldn't be .100" off on that measurement. And, if I read this date code right, I have a Christmas Break edition of this NV3500. 12/20/99. 2000 model year should have the larger bearings. So that makes sense.
Me too! I've spent a lot of time being afraid of a couple things here (and definitely the tranny rebuild). But it turns out it's really cool tearing into one of these things. It's mechanical paradise!
I bet!
Game plan here is to wait for the tranny rebuild supplies, then to hang the tranny off of the engine and install them together. Maybe as soon as next week? It kinda depends on the post man. I still don't have my single-plane intake, but it's not a big deal if I put the dual-plane intake back on there. Otherwise I've nearly run out of things to do. I mocked up a second alternator mount today. Turns out a driver-side alternator mount off of an SBC will bolt onto a 6.2 water pump, though I'm 80% sure it'll interfere with the P/S pump. But that's a back-burner idea that will hafta wait until it's back in the chassis. Definitely not a need.
Also tore the heat riser off.
It's amazing how much more open the manifold is vs. the heat riser. Though it's still 2 inches.
I should have new bearings & seals for the NP208 by the end of the day. Might hafta tear into that while I'm waiting.
Also tore the heat riser off.
It's amazing how much more open the manifold is vs. the heat riser. Though it's still 2 inches.
I should have new bearings & seals for the NP208 by the end of the day. Might hafta tear into that while I'm waiting.
It's also amazing just how much lighter this tranny is than the NV4500. 
NV3500 is 100% torn down, and parts are on order. NP208 is torn down and the main case is back together. The CUCV instruction manual is a lot more detailed than the factory manual I'm using for the transmission. That was fun, especially when it told me to individually count each of the 120 needle bearings I removed. Seems like I counted approximately a handful and left it at that. 
I found a blue 18-tooth speedometer gear inside, so I will need to swap that out.
Installing the new rollers I did count each and every one of them (2 rows of 60 rollers each). The green goo that I bought for the NV3500 project was very handy here.
And then into the case...
And then on with the sprockets. Out of the 120 rollers I had just one that needed slight tweaking (but it still didn't leave the race). Much, much better than I was expecting.
I found some wear on the chain drive sprocket.
Otherwise the case was clean and everything was in very good shape. The old bearings showed no wear and probably would have outlasted the aftermarket bearings I put in there. I reused the ones that weren't dropped into the sandbox. Mostly this was just a fun project for me to learn more about gear cases. I was surprised at how simple the shifting mechanism is. Lots simpler than the NV3500 shifting rail. I can't believe nobody has tried twin-sticking a 208. I think the planetary shifter could fairly easily be manipulated by a second shaft installed toward the front of the case.
I suppose if someone handed me an end mill and a week off work I could find this out. Someday, someday.
I found a blue 18-tooth speedometer gear inside, so I will need to swap that out.
Installing the new rollers I did count each and every one of them (2 rows of 60 rollers each). The green goo that I bought for the NV3500 project was very handy here.
And then into the case...
And then on with the sprockets. Out of the 120 rollers I had just one that needed slight tweaking (but it still didn't leave the race). Much, much better than I was expecting.
I found some wear on the chain drive sprocket.
Otherwise the case was clean and everything was in very good shape. The old bearings showed no wear and probably would have outlasted the aftermarket bearings I put in there. I reused the ones that weren't dropped into the sandbox. Mostly this was just a fun project for me to learn more about gear cases. I was surprised at how simple the shifting mechanism is. Lots simpler than the NV3500 shifting rail. I can't believe nobody has tried twin-sticking a 208. I think the planetary shifter could fairly easily be manipulated by a second shaft installed toward the front of the case.
I suppose if someone handed me an end mill and a week off work I could find this out. Someday, someday.
Few pictures of the tranny teardown. The input shaft, main shaft, cluster shaft, and reverse shaft all come out together. Between teardown and assembly the case halves get flipped several times to get the shafts clear of each other.
Main shaft:
Slight wear on the reverse gear, and the cracked bearing race shown earlier. Otherwise it all looked good.
Turns out I misunderstood the bearing change and measured the main shaft. When I measured the cluster shaft I got 1.18", exactly like I should have.
I pressed off the synchro hubs using the hammer & wood block method. Plus some localized heat. For assembly I plan on freezing the shaft and preheating the hubs in the oven. Should be fun.
Main shaft:
Slight wear on the reverse gear, and the cracked bearing race shown earlier. Otherwise it all looked good.
Turns out I misunderstood the bearing change and measured the main shaft. When I measured the cluster shaft I got 1.18", exactly like I should have.
I pressed off the synchro hubs using the hammer & wood block method. Plus some localized heat. For assembly I plan on freezing the shaft and preheating the hubs in the oven. Should be fun.
Tore down my spare case to find it also has the blue speedo gear. So this project is now also waiting for parts.
Making some good progress!!!
I hope the one that you need is not white or tan.Tore down my spare case to find it also has the blue speedo gear. So this project is now also waiting for parts.
I just tossed a couple last week that where in my scrap pile
Yeah, I need the 15-tooth tan driving gear.
https://amazon.com/gp/product/B00P8BMELY
I rechecked my math a bunch of times and wound up buying a 42-tooth green driven gear, rather than using the 40-tooth black gear.
https://amazon.com/gp/product/B00P8BKSGC
I didn't think to ask around because I didn't figure it was worth anyone's hassle for $9 shipped.
Oh definitely not.Yeah, I need the 15-tooth tan driving gear.
https://amazon.com/gp/product/B00P8BMELY
I rechecked my math a bunch of times and wound up buying a 42-tooth green driven gear, rather than using the 40-tooth black gear.
https://amazon.com/gp/product/B00P8BKSGC
I didn't think to ask around because I didn't figure it was worth anyone's hassle for $9 shipped.
I just always feel bad when I don't know what people need and trying to clean up to be able to get to things including the parts you need, I need to toss some things without asking.
Meh. That's life. I'm much more interested in whether you found the parts I need.
I wanna get this engine installed!
Alright...I haven't touched this project much this week. But we're getting closer. I have my clutch hydraulics figured out, I'm 90% done with the NP208 rebuild and 80% done with the NV3500 rebuild. I have some new 2/0 wire with which to make battery cables. New block heater & alternator are installed. Lots of odds and ends. I'm going to try stabbing the engine and trans together. Some flooding turned my barn floor into quicksand, so the engine hoist sunk in a bit. But I think it's dry again now.
The NP208 rebuild stalled because I garfed the threads on the front output shaft. I ordered the 7/8" UNF die to recut the threads, and I think I have gotten it back into the groove. But I wasn't making much progress grabbing it with my various hand tools. So I'm now ordering a proper handle to go with it. Worst case I'll tear the whole thing down again and grab the input shaft from the spare case. A word to the wise...install your front yoke before you put the whole case back together. It makes swapping shafts a whole bunch easier if need be.
The NP208 rebuild stalled because I garfed the threads on the front output shaft.
I ordered the 7/8" UNF die to recut the threads, and I think I have gotten it back into the groove. But I wasn't making much progress grabbing it with my various hand tools. So I'm now ordering a proper handle to go with it. Worst case I'll tear the whole thing down again and grab the input shaft from the spare case. A word to the wise...install your front yoke before you put the whole case back together. It makes swapping shafts a whole bunch easier if need be.
Pictures from the NV3500 rebuild. For those considering this project, it is very doable at home, but you will want to follow the service manual instructions carefully. Check your work and don't force anything. The three synchro hubs are the only tricky part, as they are an interference press fit. I stuck my mainshaft in the freezer and heated the hubs with a torch. My press was a large hammer and a pair of 6x6 lumber chunks suspended over a wooden crate.
First hub in place, getting ready to install the second:
The hub has 3 spring-loaded detent balls. Sticky grease is essential to getting these in place.
Hub in place, installing the sticky balls.
Then the shifting ring slides over the top.
Rinse and repeat for the other ones, and you should be done. However, I was not able to get the 3/4 hub snap ring seated. It was too small for the shaft. I tried freezing the shaft again but found it made little difference. I dug through the old snap rings and decided that my kit had come with the wrong size of snap ring. So I reused the old one.
The frost patterns on the frozen gears are really neat.
Then I had problem #2. The snap ring on the other end would not fit into the groove. So I tore the shaft back to the hub and pushed it further down its splines.
Finally in the proper groove.
Then I rebuilt the shaft again. It all fit correctly this time.
Finished and ready to install.
First hub in place, getting ready to install the second:
The hub has 3 spring-loaded detent balls. Sticky grease is essential to getting these in place.
Hub in place, installing the sticky balls.
Then the shifting ring slides over the top.
Rinse and repeat for the other ones, and you should be done. However, I was not able to get the 3/4 hub snap ring seated. It was too small for the shaft. I tried freezing the shaft again but found it made little difference. I dug through the old snap rings and decided that my kit had come with the wrong size of snap ring. So I reused the old one.
The frost patterns on the frozen gears are really neat.
Then I had problem #2. The snap ring on the other end would not fit into the groove. So I tore the shaft back to the hub and pushed it further down its splines.
Finally in the proper groove.
Then I rebuilt the shaft again. It all fit correctly this time.
Finished and ready to install.
At this point the instructions say to recheck the orientation of all the critical points. During inspection I noticed the 1/2 synchro ring was installed backwards. The instructions had indicated that one point faced toward 1st gear, but I had not found the mark until I rechecked everything at the end. And, of course, it was pointing toward 2nd gear. So I tore down half the shaft again (including tearing off the 3/4 hub) so I could reverse the direction of the 1/2 shifting ring. Word of advice...be careful in checking every little thing. It will pay off.
The instructions had indicated that one point faced toward 1st gear, but I had not found the mark until I rechecked everything at the end. And, of course, it was pointing toward 2nd gear. So I tore down half the shaft again (including tearing off the 3/4 hub) so I could reverse the direction of the 1/2 shifting ring. Word of advice...be careful in checking every little thing. It will pay off.
The aerosol duster was exceedingly handy. Each time I heated a hub (5 times total), the hub became hot. The assembly goo only works when cold. So when the hub was in place I would turn off the torch and use the liquid refrigerant in the duster can to cool off the hub more quickly. Just enough to keep the grease from melting. That was $3.50 well spent.
I then assembled the 4 shafts in the front case. I bought the official tool for holding the reverse shaft in place, but it did not match my cluster shaft. So I wired it in place.
Then I set the rear case in place and flipped the whole thing over for final installation. This is when the shifting rail gets reassembled.
When it was properly seated into the rear half and the reverse shaft was bolted in place, I put the front half back on and bolted it together. Tip for folks doing this build...when the shafts are properly seated you will see gears in both the fill and drain holes. When lining up the bearings you'll just see empty case.
Bolted together with oil-proof RTV. I skipped the anerobic sealer because the case machining wasn't as perfect as it had once been.
My wonderful detent plug. I might replace this one, but it's installed for now.
All buttoned up and ready to install. The shifting feels perfect, and I've replaced all bearings, synchros, and seals. At this point I'm very happy with it.
GTO slave cylinder installed. I hooked up the vacuum pump and pulled a bunch of fluid through it. But it does not pump fluid back and forth when I work the bearing. So I haven't gotten all the bubbles out yet.
I don't like how loose the lower fitting is with the roll pin, but it is consistent with the other 2 cylinders I've checked. And that's an 8" M10-M12 bubble flare adapter line with an M12 union attached to the stock squarebody hydraulic hose. 100% bolt-on, despite using parts from 3 different vehicles on a formerly automatic truck.
Then I set the rear case in place and flipped the whole thing over for final installation. This is when the shifting rail gets reassembled.
When it was properly seated into the rear half and the reverse shaft was bolted in place, I put the front half back on and bolted it together. Tip for folks doing this build...when the shafts are properly seated you will see gears in both the fill and drain holes. When lining up the bearings you'll just see empty case.
Bolted together with oil-proof RTV. I skipped the anerobic sealer because the case machining wasn't as perfect as it had once been.
My wonderful detent plug. I might replace this one, but it's installed for now.
All buttoned up and ready to install. The shifting feels perfect, and I've replaced all bearings, synchros, and seals. At this point I'm very happy with it.
GTO slave cylinder installed. I hooked up the vacuum pump and pulled a bunch of fluid through it. But it does not pump fluid back and forth when I work the bearing. So I haven't gotten all the bubbles out yet.
I don't like how loose the lower fitting is with the roll pin, but it is consistent with the other 2 cylinders I've checked. And that's an 8" M10-M12 bubble flare adapter line with an M12 union attached to the stock squarebody hydraulic hose. 100% bolt-on, despite using parts from 3 different vehicles on a formerly automatic truck.
Also, there are quite a few variants of the NV3500/NV3550 between GM, Dodge, and Jeep. Many parts swap, but it's easy to wind up with a rebuild kit for an NV3500 that doesn't fit your exact NV3500.
