Captain Obvious

I wouldn't get too hung up on the number of populated pins. From what I've seen, some of it may depend on when (and by whom), the ECU was assembled. The original first run ECUs seem to have only the used positions populated, but I've seen second source (or later replacement production units) that have all the positions populated. I think there are a number of factors at play with that. I remember someone's assembly that used plastic DIP packages inside instead of the old spider legged cans? Wheee's maybe? Definitely a later production run after the 280Z was no longer being sold new. Probably newer production of the old design for repair business.

There is lots of expert help already on the case, so I'm going to stay in the wings as much as possible, but before I go back to my hiding spot, there are two things that have caught my eye. First is this... On your to-do list was to return the AFM gear to it's original position by turning it six teeth counter-clockwise. The implication of this is that you had previously turned the gear six teeth clockwise. (Haha! Big intellectual leap by me, huh?) The POINT is... If think you are chasing a lean condition, then turning the AFM gear CW will only make it leaner: The second thing that caught my eye was the way you have the vacuum gauge and the vacuum advance connected. Something is wrong with the following: The vacuum advance signal for the distributor is not supposed to come directly off the intake manifold. It is supposed to come off a ported source from the bottom of the throttle body. And that vacuum source should be zero vacuum at idle. So something is screwy there, and your fuel pressure readings and ignition timing numbers are suspect until you get to the bottom of that. If you have the distributor connected directly to the intake manifold, then your base timing is wrong. Or if you have the vacuum gauge connected to the ported vacuum source, then your throttle plate is open waaaaaaaay too far at idle. Potentially because the thing just won't run at anything less. Also, if you're using that ported source for the gauge, then your FPR numbers may be correct because you can't do the subtraction for manifold vacuum correctly. And I agree with Zed Head... It just don't sound right and I agree that you need to double check the firing order. Also check the injector clickety-clicking with a stethoscope.

Haha! In case you haven't already figured it out from the previous posts... Those threads inside the control arms are what accepts the bolts that hold the control arm bushings in. Without those bolts, the bushings will fall out as you drive. Repeatedly.

Sorry, I wasn't trying to imply that it was a bad or stupid idea. I was just musing that the simpler the better here. You're right that staking doesn't have to retain a lot of force. In fact the only thing it has to do is resist the spring force of the springs assembled onto the plunger itself. I think if you restaked it and then grabbed the tip in a bench vise and gave the other end a tug as hard as you could pull it (in addition to the spring force), that would be a four or five times normal operation safety margin test. Maybe I'll work on that "fixture" today. Rumor has it that there's a valve seal on it's way to me. I should really have that tip re-plated first though before I put it back together. The rest of my valve pieces are in really good shape, but that tip got a little rusty.

I don't know, but I believe based on the the application that simplicity and reliability would be the top priorities over everything else. I'm not gonna mess with pins.

Haha!! Yeah, I know. Whack-a-mole works great too! Doesn't have to be dead on balls accurate.

That part is steel and is not hardened. It had to be malleable enough to deform for the original retention, and although it's not what I would call "thin" there, it will take a significant amount of force to upset the metal. I'm not sure you'll get enough force with a plastic handled screwdriver. I think it's going to require metal to metal to metal. A thousand ways to approach the task, but here's my thinking... I was picturing three pieces for a fixture to do the peening. One semicircular support anvil for underneath, and an identical piece for the top except that it is drilled on the top dead center for a punch. Then the punch would be a short stub of round hardened steel (1/8 diameter maybe?) that would fit snug into the hole and would be ground at the business end to a shape similar to the original punch mark. You can make the two anvils easy by drilling an appropriate sized hole in some 1/4 thick plate and then carefully cutting through the middle of the hole on the bandsaw. Poof. Two smooth semi-circles with the saw kerf supplying the necessary clearance between the two. Put the support anvil under the plunger, cover with the sliding punch top anvil and use the hydraulic press to push the punch downward through the hole into the valve assy. More work than just whacking it with a screwdriver, but much more controllable. You should be able to feel the rod sticking out of the retainer tip seal as you apply the force and make sure you don't go to far. That piece needs to be wobbly on the tip in order to work right.

I got one basic question to start... Do you think you are running rich, or running lean?

Nice work so far. Taking the bull by the horns and not wanting to be simply referred back to the FSM. Here's a chart I whipped up a while back to evaluate the resistance measurements from the air and water temp sensors: *This chart was created using the Stienhart-Hart Equation with coefficients derived from data points in the manual.

Nice plating! You're clearly getting better results. And I like the way you pulled the plunger apart. I wasn't sure how much force it was going to take and I didn't want to use the threads to jack the assy apart. But now that we have seen that it's not a huge amount of force, your fixture is clearly capable and is a lot less wobbly than what I did. I'll do that next time (if there is a next time). If you use one of your anvils to support the bottom 180 degrees (and spread the load), you should be able to re-peen the other side. Mine had three punch marks 120 degrees apart. How about yours? The same?

As mentioned already, if you have the correct bushings, they are supposed to be tight. I found that the brand I had didn't even fit right when new. No guarantee that all brands are the same, but here's my experiences with the poly rack bushings. Long thread, but my pics have been reloaded on page four: https://www.classiczcars.com/forums/topic/48621-steering-rack-disassembly-and-refurb/?do=findComment&comment=531913

As soon as I'm done with it? Haha! Let me see what I can come up with. You can see a whole complete poppet valve plunger in the bag in pic that Kats posted. Complete with seal already on the assembly and crimped together. So it's clear, not surprisingly, that Nissan was never expecting that plunger to be disassembled: I had mentioned it before, but the only reason I even ever started messing with taking it apart was the one that came in my rebuilt booster had been disassembled and had a new seal installed by the rebuilder company. So I knew it was at least "possible". Here's a question for ya.... What is the recommended replacement procedure for that poppet valve seal on the Mustang booster? It's included in the kit, so clearly they are expecting you to use it. Did you find any pics or instructions for the expected use of that rebuild kit from Harmon? In other words... Does the Mustang poppet valve assy come apart and go back together easier than the one from Hitachi? Is the Bendix version easily repairable or is it crimped together like the Hitachi version?

Haha! I figured when you were thinking of taking that poppet valve apart, you would need that seal. I believe replacement does require disassembly. I don't think there's any way that seal will stretch over the end for replacement without tearing it. It's just too large of a change. And the rebuilt valve I have was clearly reassembled by Cardone. I don't think it would be too difficult to build a little fixture to re-peen the end. I was picturing a half round support for underneath made out of quarter inch thick plate and then a small punch on top to press the dent in. Do it on the hydraulic press.

Bummer about cracking the bakelite disk. I would have been with you on using JBweld to seal up the small holes, but I'm not sure I would try to repair the rest of that damage. I'm thinking a replacement would be prudent. And I'm sorry that it's too late, but here's how I got my stuck retainer clip out. Couple small rare earth magnets. Very strong for their size: And this is what my poppet valve plunger looked like when it first came out. Looks just like yours: As for disassembly of the poppet valve assy... The end piece is crimped into place and is not meant to be disassembled. You can see the dents of deformed material that hold the end on. The only reason I even knew it was possible to take it apart was that I had bought a rebuilt booster and it was clear by the marks on the valve that it had been disassembled and subsequently reassembled. I don't have any pics of the "rebuilt" one, but you could see that they had "repeened" the dents that held it together. Of course, the workmanship there was suspect... It looked like they whacked it with a center punch a couple times around the circle. But the point is... They were doing it, and I figured I might try it on my spare valve. Had nothing to lose. So I cobbled together a "fixture" from cut-offs and shorts and whatever chunks of metal I had laying around: And put it on the hydraulic press to push the end off the valve shaft: Here's what it looks like when it comes apart: If I was going to be doing more of these, I'd build a better fixture for taking them apart, but since I wasn't even sure it would work, I spent very little time on it. It came apart easier than expected. Might even be a small enough force that you could cobble up a "puller" using a large C-clamp instead of using the hydraulic press. And for the reassembly, I would try to recreate the original dimples, but I won't move to that part until I get the seal from you.

Like so many other topics, seemingly simple things like that groove in the bearing can actually be quite complicated. Apparently the groove design is dependent on the application. Here's some interesting info on such things: http://www.nationalbronze.com/News/410/ Now in the application of the steering rack where the lubrication is never replenished from a pressurized source, I'm not sure how important it is at all. I'm no bearing expert, but I'm not sure the exact shape of the groove would matter much in that application.

I haven't done a coil over project, but I thought they used a slip over collar and did a lap joint. I think that would be better. Can you slip a collar over the slits after you weld them up and then weld the collar in place? I think that could buy you some time while you looked for a replacement. Another hurdle / test will be when it hits the alignment rack.

LOL. Yeah, I know. Far be it for me to suggest that someone else is doing something like that. In my defense, however... My understanding is that everyone seems to be in agreement that it's bent. I thought the "understanding" part of the problem was already over and we had moved to the "what to do about it?" part. If that's not the case, and a definitive cause for the lack of clearance to the tire has not yet figured out yet, then carry on! However, if that strut tube has been bent, then my humble opinion is that I think replacing instead of trying to bend back is the proper course of action.

Buy... Another... Strut... Housing!!!! C'mon man!!! And I thought I spent a ridiculous amount of time on things that I never should have done in the first place. It was tweaked. Enough to exceed the plastic deformation rating of the material. It'll never be the same again. Buy another strut housing!!!

Oh, and BTW... It's not just you. On my first booster disassembly, it took me an hour to figure out how to get that clip out. Mine was a little gummy and a little rusty and if not for that, it probably would have fallen out by accident. But between the rust slurry making a little sticky and the not knowing what I was doing, I spent at least an hour on it. If it's clean, put it on the bottom side, press the plunger slowly, and it will fall out simply from gravity.

Yes, there is a little U shaped retainer at the bottom of the plunger that holds it in. But the only thing that holds it in is friction from the plunger spring. If you push the plunger in a little, it will unload that pressure and that clip will most likely fall out unless it is a little rusty and stuck. If that's the case, a small magnet can help pull it out. But to answer your question... Yes, you have to take the pressure off. And that is done simply by pushing the plunger in a little bit. If you push it in a lot, it will spring load in the other direction... There's a small "sweet spot" in the middle where that clip isn't under any load. In fact, the only thing that holds that clip in when you pass through the sweet spot is the rubber diaphragm sitting in the groove. I've got some pics that would help describe, but my picture hosting server is not cooperating today.

Oh, and your clamshell tool looks just like mine! I screwed some two inch long 2x4 cutoff stubs to the edge so I can use my big bench vice to turn the planks. I thought I had taken some pics of that procedure, but I can't find them. Probably misfiled...

The part at 7:00 to the port is the poppet valve seal. That's the part I want. In fact, in preparation for you to send it to me, my spare poppet valve fell apart earlier today:

Here's the comparison pic between 240 and 260 from that other thread: I'm wondering if anyone has done a similar comparison for the 280's.

Leon, Other recent suspension discussions reminded me of this thread and I wanted to circle back around a little. First, I took a look at putting a zip tie on the strut shaft, and with the bellows in the way I don't think it's possible. Just not enough room in there to lift the bellows out of the way. You might be able to get in there and do that if the bellows were not installed, but with the bellows (stock style with the bottom retainer clip) installed, I don't think it's possible. In another thread, there was discussion that they changed the spring perch location between the 240 and the 260. Lowered it about an inch for the 260: https://www.classiczcars.com/forums/topic/38373-240z-eibach-springs-in-260z/ Have you ever seen a similar comparison between the 260 and the 280? In other words, do you (or anyone else) know if the front perch location is the same from that point on to the end of the 280 run, or did they move it around again for one of the years?

Cool! I did a bunch of digging around on the website for the guy you got that kit from, and I noticed that he was using the same pictures for several of the kits. "Stock photo" and not necessarily accurately representative of what they parts really looked like. I was worried that what you saw might not be what you got. Can you take a pic of the other parts besides the diaphragm? I'd be interested in taking the poppet valve seal off your hands and seeing if I can get that onto my old booster plunger. Also, are there any numbers cast into the new diaphragm? When I had my rebuilt booster apart, there were numbers on the diaphragm inside that I wrote down somewhere. I'm wondering if they got their diaphragm from the same source. I wonder how many people in the world are casting that part.... In other words, I'm wondering do all the rebuilder companies get their stuff from the same source, or do they all make their own?