Jeff G 78

Thanks for the info Steve. What type of threads did you go with on the stud (all-thread) and what pitch? What type of thrust bearing are you using? As for the big wrench needed, I thought about taking a cheap black oxide 1-1/2" (1-5/8" for acme) socket and cutting it in half to remove the square drive so it can slide over the 1" all-thread. The socket could then be made into a jumbo wing nut with some spare steel and some welding. It would be cheaper than a wrench and, if designed right, would be easier to use. Please post the pics of your new puller when you can.

Thanks Lee. Let me know what kind of feedback you get from ZCOT members. A cross-drilled hole would be a simple add to install/remove the rod from the spindle pin. Depending on the amount of space left beyond the nut once the tool is attached, the hole location might be best at the far right end as you look at the drawing. That way, the rod could be installed/removed with or without the pipe in place and the hole could be used to hang the tool on the wall for storage.

OKAY, This drawing is a wee bit better. It's NOT a proper drawing since I decide to mix sections and plan view for clarity. Let me know if you have any suggestions on my drafting techniques. It's been a LONG time since I last did a proper drawing. I did the drawing in AutoCAD 2000 (old school), printed it and scanned it as a picture. If anybody wants the CAD file, let me know.

Hey Cap'n. If you go to McMaster and search "acme" you will see the threaded rods. The one I chose is the alloy ASTM A193 Grade B7 which is a chromoly 4140 quenched and tempered to a 4142. So yes, it is hardened and yes, it can still be machined. For now, I will buy just a 1"-10 x 12" rod as well as the same thing in a standard thread 1"-14 x 12" which is the same material spec as the acme rod. It certainly won't machine like a low carbon steel rod, but my buddy says it will do fine.

I asked my friend and he said that 4142 machines fairly well with lots of cutting oil. I'll post some links to the couplers in a bit. I'm playing with Autocad right now.

Zombie thread alert! Welcome Datsun Clark. Z cars work fine for tall people as long as you don't try to cage and race them. For the street, all is good.

I'll ask my buddy at work how hard it would be to drill and tap the rod. He does a ton of machining, so he'll know. After looking at the pipe fittings again, I *might* be able to keep the rod a full 1" diameter and grind a flat into the 1" pipe coupler to clear the LCA flange. The 1" coupler has an O.D of 1.77" and the LCA flange can handle 1.5", so it might just work without adding extra machining to the rod. I'll buy a coupler and experiment before I turn the rod down to 3/4". Yes, the 1" iron pipe will slip over the 1" all-thread. I have tried it with 3/4" rod in a 3/4" pipe and it fits fine. I will not be using thrust washers. I will be using a thrust bearing. The Z bearing holds up the corner of the car, so it should work fine. I agree that a thrust washer would not work nearly as well. All 1" hex nuts are 1-1/2" across the flats from what I can tell, so yes, I'd need a 1-1/2" box end wrench of a big adjustable wrench. I'll check around and see what I can find. I really don't like giving HF any of my money. EDIT: I just rechecked and the acme hex nut is actually 1-5/8" across the flats. I guess I might need the jumbo wrench set after all since the standard threaded nut is a 1-1/2". I just looked at the dimensions of another type of coupling and it is only 1.58" O.D which might just fit under the LCA flange. I think we solved the issue and the rod will no longer need to be machined down to 3/4".

The 1-1/2" wrench would need to fit the nut, not the rod. I'm not sure you could get enough strength without distorting the nut if you welded long arms to it. They do sell large wing nuts, but only in 1"-6 pitch and they are expensive. I found jumbo wrench sets at Harbor Freight for about $45. They might also have them individually in the store??? I HATE Harbor Freight, but how bad can a giant box end wrench be? A large adjustable wrench could also be used. I priced everything needed for the puller at McMaster-Carr. For the standard thread tool, the rod, nut, and washer is $17 and some change. Add a 1" black steel nipple, a 1"x3/4" reducing coupling, and a 1" coupling and the total material cost would be around $25-$30. I am going to ask a friend to let me use his lathe to make the prototypes, so there should be no additional labor for my trial tools. The acme thread puller will be about $45-$50 total. I plan to use an old spare strut bearing, so that too is free for the trial puller. Once everything is proven-out, I would need to procure some sort of thrust bearing for those who don't have a stash of spare Z parts laying around. I only have a few bearings handy, but I might have more somewhere in storage. I did check the specs on the 1"x3/4" reducing coupling and the 3/4" long machined area of the rod should work fine. The coupling is only .55" long for the small end. What am I missing??? EDIT: McMaster has a thrust bearing for about $20. Ideally this would only be needed for those who couldn't find a free strut bearing.

Wow, it's been close to 20 years since I put pencil to paper and back then, I had a drafting machine. Tonight, I just have a few triangles and an engineering scale to work with, but I'm slowly getting a drawing put together. I'll try to get enough done tonight to post something, but NO LAUGHING at my work. :stupid: Here is the all-thread drawing. I will try to do the pipe, fittings and bearing tomorrow night. BTW, I might need to increase the length of the 3/4" diameter section of the all-thread after I measure the dimensions of a 1"x3/4" reducer.

Lee, Necking down the all-thread would work as long as it had a smooth transition between the 3/4" and 1" sections. Otherwise, it will have a stress riser and fail. You could then use a 1" steel pipe with a 1"x3/4" reducer to go against the bushing. The drilled and threaded end of the all-thread should also have a chamfer leading into the threads to match the chamfer of the spindle pin where the threads meet the shaft. At the nut end of the pipe, another 1" coupler could be used to ride against the thrust bearing. I took a few measurements tonight and the O.D. of the 3/4" coupler (or small end of the 1"x3/4" reducer) is ~1.5" and it is about the perfect diameter for the LCA bushing. The I.D. of a S30 front strut top bearing is a bit over 1", so that would work great for the 1" all-thread to pass through. I think we are getting really close to having the best possible tool. Using an acme thread *might* improve the tool, but it might make it less efficient due to the course threads. I can buy 1"-10 acme or a 1"-14 standard thread. The acme rod and nuts are about twice the cost of the standard threaded rod and nuts. I think I will go forward with the tool using this design. I might buy 12" of each type of rod and do an A to B test. By testing both thread types of exactly the same tool design, we can answer the thread question once and for all. If I get REALLY ambitious, I might try to remember how to use CATIA and make a CAD drawing of the tool. In the mean time, I'll draw it by hand tonight and post it as a picture. It will be crude and 2D, but will be much quicker than me trying to use CATIA for the first time in about six years. Even back then I was a complete novice user.

You can rent a hoist from any tool rental place for a few bucks or buy a used one off CL and resell it when you finish for the same amount of money. I see them all the time for $100 - $150 used.

Lee, I spent some time looking at a puller I borrowed. It is the typical cheap 3/4" all-thread with a drilled and tapped end for the M12 spindle pin. The 3/4" black steel pipe has a 3/4" coupling which just fits under the control arm flange and is a very good fit to the bushing. When you step up to a 1" all-thread, how are you dealing with the outer pipe where it presses against the bushing? I would think that it would catch the LCA flange unless it was notched on one side. I can take pics tonight if my post didn't make sense. Let me know.

Is there a reason you didn't pull the engine? It takes half as long to pull the engine and rebuild it on a stand compared to fighting it in the car. It takes almost no time to pull the engine from the car. There is also much less risk of mistakes when reassembling everything and it would have also made the engine bay refresh easier. Good luck with the rebuild. I just think you are doing it the hard way.

Has anybody received a confirmation email yet for their raffle entry? Just wondering.

Agree Leon. The only problem is that a 260 can sometimes be more difficult for owners who haven't already owned earlier and later Z cars. My 260 is the 11th S30 I've owned in the last 25 years, so I can usually figure out pretty quickly if a needed part is 240, 280, or 260 unique. It also helps that it's a race car and I've touched every part on the car, so there is little mystery left.

The only hazard with the 260Z is buying replacement parts. It's really easy to get the wrong parts because of the changeover from 240 to 280. My late 260 has been quite a challenge. I've had people state that all 260Z's came with points, yet mine has (had) an electronic dizzy. I swapped it out for a ZX unit due to a bad control unit. The 260 control units are a one year only part and they are hard to find.

Cool! When did the "Like" button come online?

Welcome Duckman! The weight you list for the 240 is correct, but not the 280 weight. I believe you are mixing curb and GVW weights. The actual weight of a '77-'78 is around 2800 lbs. The big bumpers account for about 80 of those 400 pounds. The rest of the weight is a combination of extra carpet, FI system, rear swaybar, body weight for stiffness, door beams, and crash standards. The 240 bumpers will make a 280 feel much lighter because the weight comes off the far ends which reduces inertia of the 280. There are brackets available and the swap is reportedly fairly easy. I have not done it yet, but many have and it doesn't sound too bad. Good chrome 240 bumpers are getting hard to find, but there are SS replicas ($$$) and fiberglass replicas. Since the small chrome bumpers do almost nothing anyways in a crash, fiberglass isn't a bad way to go. They also make CF bumpers, but they are mostly fiberglass with some CF and the quality isn't great. The 280 is heavier, but if small bumpers are installed, the rest of the added weight isn't "bad" weight. The FI system is one thing you can ditch if you like the simplicity of carbs. The FI system was great back in 1975, but it's a dinosaur today. If you want FI, install an aftermarket system like Megasquirt. All S30's can be made to ride and handle like you want. The best advice is to buy the best car you can afford and don't worry about the model. I'd rather have a rust-free 280 than a rusty 240 for example.

My R180 was making that sound on the race track right before she went kablooey. The bearings went and took the ring gear out. Have you checked or replaced the fluid? Ours was low on fluid which started the failure. It was the one thing on the massive pre-race to-do list that we didn't complete.

Looks great as always.

I hear you Leon, but I'm an engineer and I like to tinker.

I have done some research and I need to rethink my plan. I was going to use 3/4"-8 acme threaded rod, but once I looked at the actual dimensions of the acme rod, I realized that there will not be enough material to drill and tap the end of the rod for the M12 spindle pin. The problem is that the acme threads are rather tall, so the root diameter is rather small. I fear it will be weak and fail where the spindle pin is threaded into the end of the rod. The simple solution is to go to 7/8" acme rod, but it can only be had in 7/8"-6. I'm worried that 6 threads per inch will make it harder to extract the spindle pins. Another issue is that the cost would go up even higher with 7/8" acme rod. The nuts, washers, and bearings all get more expensive as the rod grows. I am not giving up and I plan to make at least one prototype puller as soon as I figure out the best combination of parts. If I can get acme threads cut into a coupler like Michael's puller, then I can revert to a smaller acme rod and have an adapter coupler as part of the design. Acme nuts and couplers are WAY more expensive than standard threaded parts, so It would have to be custom made. The other option would be to weld the coupler to the acme rod and avoid the expense of cutting acme threads. Either way, my puller will use bearings and thick washers so it can be used over and over without mushrooming like Michael's puller shown above. Like I said before, I can buy a puller, but I want to engineer a better one.

Michael, the '75 reel is bolted to the roof. They moved it in '76 to the shock tower.

1/3 the price? So what? I replace my fluids once every few years at most. What's another $10?

I found them on ebay and the quality is very good. Do a "M12x1.25 shank lug nut" search and you should find the seller. Quite a few years ago, I bought a set from a chain auto parts store and they are crappy. The threads are not as tight and I had a wheel come loose on my race car.