Woohoo, I'm back on this project. I had a few interruptions like my EV riding mower battery acid leaking into the motor which created the need to rebuild it, and some house stuff. Is good to be back working on the Insight though as I'd like to get it back on the road shifting smooth.
So, last night I got to modifying the gear synchros. The process is pretty easy really, but I'll try to go through it step by step. I used
this guide on Insight Central to help me out as well as the service manual. It is really easy to get parts turned around and the service manual indicates anything that needs to be put on in a specific direction.
Step one was to remove the shifter mechanism. Four 10mm bolts to the bellhousing will free it. Its the bracket on the right. The one on the left with just two bolts I didn't touch.
With that free, you can lift the shafts out of the bellhousing. You'll also want to pull out the reverse gear. From left to right we have the counter shaft, then the reverse gear, and then the input shaft. The one we'll be dealing with to fix the 2nd gear synchro grind is the counter shaft.
While pulling the shafts out, some of the rollers came out of the counter shaft bearing. No worries here, I grabbed a needle nose pliers, and pushed them back into place. They loosely snap back into place.
Here is what you're bellhousing will look like now. The differential is the only gearing left in the bellhousing.
I went ahead and removed it to get at the magnet in the trans. This collects any ferrous debris in the trans and keeps it out of the gears and bearings. As you can see, there is a decent amount of buildup on it. It just gets cleaned up and reinstalled.
Alright, back to the counter shaft. First, we have to remove the nut on the end of the shaft. Its similar to the axle nuts where you have to pound out the bend end so it can be unscrewed.
NOTE: this nut is reverse threaded. I put the shaft in my vise with a thick rag around it so the gear teeth wouldn't be damaged. This didn't work great, but it did work. I'd recommend wood like the service manual says. I ended up using 30mm socket (which felt a bit loose), and my 18V Makita impact driver to get the nut off.
With the nut off, you can start removing the gears from the shaft. Some are fairly lightly press fit on, while others are slip fit. The IC guide says to drop the shaft repeatedly on a wooden block to get the gears to come off. For me, this worked to a point, but then things stopped moving. So, I got out this big gear puller that I have. I made sure I was pulling against the hub of the gearing, not the teeth (thats where the big part of the puller comes in). This worked quite nicely.
With the first few press fit pieces off, there was only one very lightly press piece to go. I dropped the shaft threads down on a 2x4 on the concrete floor and it popped off nicely along with the rest of the gearing. Here is a shot of everything laid out.
If you pull out the synchro (left), you'll notice it has a few pieces to it. This shows most of them.
There is also a metal ring (spring) that goes on the right piece. Its not shown because I didn't notice it was even there until later. The piece on the right is the one we will be modifying.
Upon closer inspection, you can see what is happening here. There is a groove starting to be worn in the piece. This isn't nearly as bad as the one in the guide on IC.
Here is how things fit back together.
The solution to this problem is to simply grind the tabs off of the piece. I did this with a dremel and a course sanding bit on it. It makes pretty quick work of the brass with only short stints to cool the part off so you can hold it.
You'll need to rinse and repeat this for the other synchro set on the other side of the selector.
After that side is done, you can start putting everything back together. Even though I was trying to be quite careful with everything, its really easy to get something turned around. This is where the service manual really comes in handy. I'll post a picture of it and put it in this post for reference.
Here is one example, this part has those slots on the top face all the way through it on the bottom, but only most of the way through it on the top. This is referenced in the manual.
Once you get to this step in the assembly process (first gear with the long sleeve), you'll need to start pounding parts on. For this, I used a 1.5" exhaust pipe which I had laying around. All the parts in the trans that are steel are hardened, so using a mild steel pipe to pound them on is just fine. I used a shot filled rubber mallet to pound it on as well. A regular hammer would be fine too I'm sure, but it'll mar up the pipe for sure.
Next, continue putting pieces on one by one. The bearings are the toughest to get aligned. Make sure you pound them on by the inner race (the inner ring of the bearing), not the outer as that'll ruin them. For this, I ended up using a deep well socket.
Finally, put the bellville washer on. It should be oriented so the flared side is toward the bearing. Now, spin that REVERSE THREADED nut on again back to where the paint mark lines up with the key slot cut in the shaft. No need to torque it to the correct value. You can bash the nut back down to keep it in place.
Wow, this turned out to be a super long post! I'll continue as I do the input shaft bearing and seals later this week.