Captain Obvious

And since motion is such an important part of the concept, here's a video of the prototype rig:

Hi Kats, I got some time to work on a proof of concept for the retaining collar. Since this is just proof of concept, I took several shortcuts. For example, I did not drill and thread the center and I made the taper collar out of aluminum instead of steel because it is easier to work with. I also made the angle 45 degrees instead of 60 degrees because that is how my lathe was set-up and I didn't want to change it. None of those affect the viability of a test of the retaining feature. So here is my test rig: I included a slight undercut on the shoulder and a small counterbore on the taper to provide material to forge into place to retain the collar. I'm not sure it was really necessary, but I'm just making this up as I go: I tested the viability first with the portion through the ring longer than necessary so I could see the change in material from the forging operation. Here is the first forging on the press, using a hardened bearing race as the forging tool: It worked quite well to retain the tapered ring. Here's the displaced material. Under magnification, you can see a small amount of flared out material at the corner of the shoulder: And here's the part after the second forge test. I cut off the original forged area and did it again with the shoulder cut off closer to the ring. It's not perfect as the surfaces don't line up exactly, but I believe someone who really knows what they are doing could adjust a couple dimensions and hit it spot on. Maybe even I could hit it after one or two more test parts:

I still think a compression test will highlight or rule out a multitude of potential issues, but if that doesn't come up with anything, then I've got one WAG based on past experience. Let me tell you a story... I once had a car that ran rich for several reasons. The bowl level was a little high (because I was too lazy to fix it), the jets were a size larger than stock (because I was a kid), and the accelerator pump linkage was a little too touchy and set off a burst of gas with too small of a pedal movement (because I wasn't smart enough to figure out how to fix it). Also, when I would park the car hot, it would percolate some fuel from the carbs and bubble a little over into the intake manifold. During the hot summer months, every now and again it would make this big "whoosh" sound while cranking, and it would let out a big cloud of whitish smoke, and it would then smoke for a couple minutes until everything seemed to settle back out to normal. Looking , back, I believe what was going on was that through the rich running and the percolation, I was mixing unburned gasoline in with my oil in the crankcase. This would actually create a volatile gaseous mix of air inside the crankcase, and if it reached the right mix of air to fuel, would spontaneously burn off as I was cranking the engine. And after an "event", it took a couple minutes to burn off the residue that got burped (vurped) into areas where it didn't belong (like into the crankcase ventilation system). Like I said... WAG, but my question would be: What does your oil smell like, and when was the last time you changed it?

Did you do a compression test? Can you see any holes in pistons looking in the spark plug holes? With the plugs out, you should be able to move the pistons around pretty easy and get a decent look at all the piston faces.

Hi Kats, Thank you for the sketch and video showing the taper collar spinning independently of the rest of the nut. And your English is not the problem. The problem is me overstepping my understanding and making assumptions about how something is put together without ever examining one in person. Thank you for your patience. I do not believe the retaining feature that holds the collar in place is a separate piece. I still believe there are just to pieces to the assembly. I do not see any seam where the face of the shoulder meets the shank. Looking at the picture you posted here, that face appears to be integral with the center portion of the nut: With that in mind, I suspect they forged the metal outward slightly to deform the shank a small amount and therefore retain the collar. They may have machined a thin section of material to ease this process. There appears as if there could be a jagged burr edge of extruded material visible on the silver plated nut on the right. I do not see the same burr on the yellow plated nut on the right, but it could just be better processing on that part. It would only take a small amount of material interference to prevent that collar from slipping off. In application, all the force would be in the direction to press the collar towards the hex portion and away from the retaining feature. It seems the retaining feature really only needs to be strong enough to keep the collars from falling off during shipping and handling, and while rattling around in a toolbox. Some other less likely ideas... 1) They undercut the shank a tiny amount and heated the collar (and maybe chilled the nut) and then slipped the two parts together while they were at very different temperatures. Once at the same temperature, the parts would be held together. 2) One other wild idea is that there are retaining pins inside the nut body that were forced outward before the threading operation. Would you like for me to make one or two to test some of the ideas above?

Thanks for the pics and info guys. I've (thankfully) not yet had to mess with that part of the car and I appreciate the education. I haven't studied the design at all, but the general concept for all the rubber bushings on the car is that there is no direct metal to metal contact between the two things being connected together. The center metal cylinder would be tightly pinched between the metal of the washers, but the rubber would isolate the outer portion of the bushing.

I think the longer it goes without them changing back, the less likely it is that they ever will. Honestly, I think if they were going back, it would have happened by now. I wonder if they are publically traded, and what the last two months of stock value look like...

Well I wouldn't be so quick to condemn the motor without a couple diagnostic tests first, especially in the middle of the driving season. Compression test would be high on my list. I'm still hoping it's not something serious. I don't know how long it takes to burn through a piston, but I would hope you would have heard some pinging in order for that to happen.

Either of those washer designs will work just fine on the inboard side of the spring. They just cheaped out and used the same one for front and back locations. If you're going for 100% originality, then have at it, but if you're just looking for functionality, you can use the quarter-turn locking washers on both sides of the springs. As long as they are large enough not to slip through the holes in the brake shoes (which I assume is the case), then it should be just fine.

Holed pistons are one of the possible outcomes of running very lean. You weren't getting like 35 mpg for the past couple weeks or anything, where you? (Just kidding... Here's to hoping it's something simple and not serious!!!)

Haha! Yeah, I guess that's true. I can think of several beers that are worth less than ten cents to me. For some beers, the can would be worth more to me empty than full!

So let me poke around this a little more. When you noticed a difference between the two, and "fixed" it by putting less oil in one of them... I'm assuming you were putting less oil in the one that was harder to lift, right? And by doing that, the two of them were closer to the same. If that's the case, then I claim that the one that was harder to lift was the one that was actually working CORRECTLY, and the check valve on the other one was screwed up. So by starving the good one for oil to make them equal, your broke BOTH of them. In theory, the check valve damper should still work even if the caps are a little loose, but they should be snug. They are, however, sensitive to alignment, and that was the problem I was having. I think one of my stalks was tilted to the side a little. Not enough to prevent the whole thing from fitting down into the carb, but enough that it was preventing the damper from working. That should be identifiable by swapping the two dampers between the two carbs. A check valve issue should follow the stalk. About oil level: You can fill the tubes all the way to the top. Worst thing that will happen is that a little oil will spill over the edge and run down into the carb for the engine to burn. In short, you cant really use too much. It will find it's own level if you put in more than necessary. About how fast it goes down: There was some discussion a long time ago about such things, and my answer is that it should never go down. Although there are documented cases where some people are positive they need to refill theirs every now and then, I'm not sure why. But with that in mind, you should check it every now and then. Monthly maybe?

Well I'm probably going to be manning the hydraulic press tomorrow, but not for a Z application. I'm elbow deep on wheel bearings for the family Truckster. But while I'm messing around in the drawer where I have all my short leftover drops, drifts, and scraps and stuff, I'll look to see if I can jar brain cells about exactly what I used. You know you can press them in or out from either side, right. What about flipping it over and changing direction? I'm sure you knew that, but that's my name...

Tapered? You got a pic? My PO put poly in there and I haven't done anything about it yet, so I've never seen it disassembled.

Wait, so that collar actually spins free from the shank? It's not pressed on tight? That's more difficult. Nice feature though!

Don't you think FULL beer cans would be worth more to me than empty ones????

Glad to help. Only reason I even thought of it was because I had removed the same brace not long ago. I took the cheaters way out and put blocks under the tires to keep the suspension loaded while I had the back end up high enough to get under there.

Jason, he had posted a pic from the other end earlier in the thread. You can clearly see the joint line between the two parts of the assy in that other pic as well:

Haha! I understand completely! It's working so much better than it used to that it's changed position on the priority list. Glad you've made such an improvement!

You need a tube of the proper diameter to use as an anvil. I don't remember if I had to make something, or if I already had something laying around. Just like you did for the fronts, only the dimensions are a little more critical.

Glad you got rid of the clunk!! Just one comment/question. The rubber portion of those inboard control arm bushings are clamped into place by the brace you removed. With the brace removed, the rubber can rotate. Point is... If you had the wheels hanging when you took that brace off and put it back on, I believe there's a risk that those inner bushings rotated changed position. Did you do the final tightening of the hardware with the car on the ground (or the wheels suitably loaded)?

Kats, Here's a crude sketch of how I believe they made those lug nuts: They could have made the entire nut from one piece, but they would have needed to start with the lager rod and they would have needed to create the hex portion in a different operation. Making hex shapes on a lathe is a more difficult thing to do, so if you start with hex shaped material, then everything is simple lathe work. If you have to actually cut the hex shape, you need a more complicated machine. You may even have to transfer the parts to a different machine completely in order to cut the hex. Starting with hex shaped material allows them to do everything on simple lathes and also reduces the amount of total material they have to remove in order to create the final part. One other advantage to using two parts is that it allows them to use different materials for the two portions. I don't know if they did something like that, but for example, it could have allowed them to do something like use a hardened seat on the tapered locating washer while still having a more ductile unhardened threaded portion.

That schematic has Lucas written all over it.

Yeah, that's just not cool. Funny, but not cool!

I copied the bushing info over from the other thread. Thanks for the links and info. I'm sure there's something that would work. We just have to find it!! That first bushing from RIdetech looked interesting until I saw the ID. It won't fit over the bolt sticking down.