Zed Head

Head bolts, cam tower bolts, front cover bolts, all the same issue. Steel bolt in aluminum substrate. Metal stretches and compresses. It's elastic. The high end head bolt guys use a stretch calculation for their tightening. So many degrees of turn equals so much force exerted, based on bolt stretch. It's just one of many things that might work. Probably comes down to what operations you're comfortable doing. The welder likes welding. the chemistry guy likes adhesives, the machinist-type might like the drill and tap idea. You could probably paint the inside of the head at the crack with glyptal and be fine. I don't even really know what glyptal is but race engine guys coat the inside of their blocks with it. Apparently it sticks. http://www.glyptal.com/

A thought that popped in to my head a day or two ago - drill and tap a hole through the cracked piece in to the meat of the head, countersink the loose end, and pull the crack closed with a small screw.

In principle, yes, the pin end threads are meant to lock the inner sleeve solidly to the casting. So, extending the concept, the casting, pin, inner sleeves, washers and nuts all become like one solid piece of metal, capturing the control arm ears. But I think that the ends of the pin do see a strong tensile force at times through the washer, nut and threads. One ear of the control arm presses on the washer, the other ear presses on the casting. The ear of the control arm pressing on the washer stretches the pin, and the lock pin sees the load. Everything has some degree of elasticity. I didn't really spell that out up there, not sure I was even thinking of it clearly. But it is there! I pondered this long ago when I was looking down that casting hole with a rat tail file knocking down the lock pin hole deformation so I could get the pin back in. And there's the leverage to factor in when the control arm gets twisted, which it does under acceleration and braking. Constant twisting and levering, opening up that sleeve/casting interface, stretching and releasing the pin. It looks like a great idea on paper, not knowing how loose everything will really end up when all of that rubber is inserted between the metal pieces. Best laid plans. Anyway, that's my theory. Morning coffee.

"No brown"? Euphemism? You need a special tool, I think.

I think that it's driving forces that cause the deformation. When the spindle pin is locked, the pin and the casting become essentially one piece. The loads of the wheel are transmitted to the transverse links (aka control arms) through either contact with the casting on one side or the nut, washer and pin on the other side. The pin gets loaded back and forth and that load gets transmitted to the casting through the pin. That's where the deformation comes from, I think. That's why some spindle pins slide right out and some don't. They both got torqued to the same spec at the factory. If you leave out the lock bolt then the pin slides back and forth in the casting as loads shift. Hard to tell what the engineers intended when they put that package together. Maybe the lock pin is mainly for manufacturing ease, or maybe it has am automotive purpose. Who knows.

Three heat sources are there - conductive (what you're talking about above), radiative (anything hotter than the fuel line will radiate heat across space to the colder object), and convective (hot air blowing over colder objects and losing heat energy). They're all in play and hard to tell which way the heat is going, in or out, or which one is more powerful. I feel nerdy now... At the other end of the circuit, the return line in to the tank, the fuel is bringing heat back from the engine bay. The tank contents warm up over time. Could be that deadhead systems don't benefit from insulation and return systems do. Or the size of that orifice is critical for more than just pressure. Cool fuel. Didn't someone mention insulating the mounting points of the fuel rails, somewhere back in this thread or another. That could remove the conductive path. Interesting topic. I've put lots of thought in to the EFI analog. I have insulation for both convective and radiative heat sources, heat from the exhaust manifold, but left the rail (aluminum) uninsulated so that it could lose heat from the injectors. The convective effect seemed to be pretty large, lots of heat coming up from the hole in the center of my exhaust heat shields. Tiny hole, lots of channeled hot air. How about a radiator for the fuel?

They're in the Service Manual. Engine Mechanical, Specifications.

Just realized that everyone is focused on the engine bay, but it's really accumulated heat energy that matters. If the gas in the tank gets warm, then that extra heat energy in the engine bay will have more impact. Low fuel level probably "locks" faster than a full tank. Heat from the road will radiate up and and transfer to anything moving over it, even at high speed. I wonder if insulating everything, including the tank, from back to front would help. Even just a good shield between the tank and muffler might help. Many of those shields get lost or removed. Lowered cars might have more problem than standard height, from both radiative heat and lower air flow. If I had the problem, I'd insulate everything I could find.

Well, good luck with it. I'll just point out another inconsistency, the kind that has the taint of scamminess. You say you want to do a service, and that you "scrub through Craigslist and eBay weekly to aggregate ads " but still require information. Why is it required, if you're going to scrub/find it anyway, and you're doing a service? Those two things don't fit together. That's when people start looking closer and wondering where those spam e-mails or phone calls came from. I know that there are training courses out there about how to monetize people, on the internet. But if it's too obvious, people will reject it.

Seriously, I, and probably others, hope you're for real. But there doesn't seem to be a lot of substance, and there is some risk. You're spread thin. http://www.totalautonetwork.com/

Another thought - Maybe siteunseen missed the part on the contact form about sharing., and TAN shared the data with the "cash buyer". If so, that's on TAN. Additional information collected, tracked and stored via an SQL database includes messages, comments our other data directly submitted through this site. How Personal Data and Information is Utilized The following are the ways in which visitor data and information is used: To customize this website for a more enhanced user experience To send website communications To share with third party providers (only after permitted by visitor, or as explicitly designed by contact form or other input mechanism)

Let me see if I can do some mediating/moderating/arbitrating. Apparently siteunseen used the site to try and get his craigslist ad listed. He gave his email address. Whoever he was dealing with would not post the CL ad unless he got a phone number. siteunseen did not want to give his phone number and thought the deal was dead. Subsequently siteunseen has received phone calls from irritating people and thinks that they came through the 240zforsale site. Total Auto Network AKA 240Zforsale, to be known henceforth as TAN, is just pulling content from the internet to build a web site. It's unclear who siteunseen was talking to or if it's connected to TAN. But the coincidence is suspicious to siteunseen. Note to TAN - this site, the CZCC site is where we "chat about zcars". If we call your number and it's not blocked then you can add it to a list and sell it to telemarketers. That's not good. If you get our email address you can sell it to internet marketers also. Not good. The problem here is that you probably have many internet aggregation sites, making a few dollars a day on each one, not just Datsun Z cars. It's one of today's industries. So you may or may not be a true enthusiast. That's where the Bourbon Street comparison comes from, I think. Nobody knows you and you just have a bunch of copied information on a web site. And the one guy that's interacted with the site came away annoyed. So, as a businessperson you need to work on customer interaction quality. It appears to be lacking. Why would anyone call a stranger to chat about Z cars? Make the web site easy to use and clear about what comes from it. What can the customer expect? If you're truly a Z car enthusiast, offer some knowledge in a few of the active threads. Tell us about your other aggregation sites before we find out. Tell us about things like your Twitter account. Put all of your web site addresses on your Twitter account. So we know everything. The internet is full of cons and you're just a new unknown face. You have to prove yourself. If you don't know squat about Z cars, or Datsuns, just say so. https://twitter.com/totalautonet The site looks like it might be interesting to certain people. Not much use though if you're not close to CA, FL, GA, or TX.

Got any old aluminum castings? Crack some and experiment. I still think a Loctite compound might work easily.. I didn't look through all of their products but wouldn't be surprised if there was a "crack fixer" compound in the list. I Googled Loctite metal crack repair and http://www.loctite.com.au/metal-filled-compound-4081.htm

The spindle pin has to rotate so that the slot surface is parallel with the flat on the bolt. If it's a tight spindle pin you night have to help it. Rotate the pin back and forth while tapping the lock bolt. Nissan instructions assume that everything is shiny and new.

To be clear, you're not the owner of THIS site (the ClassicZcars site), you're the owner of this site - http://240zforsale.com/about-us/ the topic of the thread. I did a double-take when I saw your first sentence. Thought maybe we'd finally worn Mike out. Somebody already called you, in Post #4 and #6, and wasn't very pleased. Why don't you address those posts directly? He is a very trusted member here. You won't go far until you do. Good luck.

You might find that the piece cracks off if you wiggle it. Then you could clean it thoroughly and fasten it back where it belongs. I was going to suggest brazing or soldering before, but thought you were avoiding taking the cover off. I've seen JB Weld fixes on tougher spots than that though, That would probably be fine. No real load except the bolt tension. Looks like somebody might have tried to fix it before by the silicone-looking goop in the seam.

I did not know that. More learning. sb did say L28 block but it's all looking like low CR L24. Reading back looks like he meant that he took the L24 head off to use onthe L28 but changed his mind about the L28 since the L24 was in good shape. Diseazd seems to know what's going on. Collecting the facts, it looks like a rebuilt, ovebored low CR, 1973 L24 with an E31 head. Maybe it could have just been left together and run? Surprise.

Does BMW use the same goofy front cover scheme, with bolts torqued orthogonally on the same general piece of metal? I was just looking at The L6's front cover bolt arrangement. If you get the timing cover on the low end of its hole/bolt tolerances you end pulling across a fairly big unsupported gap when you put the top bolts in. Anyway, I wonder if flushing it with a good solvent, maybe with vacuum behind it, then using some Loctite thread sealer would do it. Made to wick in to tight spots, fill the gap, stand the heat, not too sensitive to oil, etc. Easier to burn off than epoxy if you do need to weld. http://na.henkel-adhesives.com/loctite-industrial-assembly-repair-13281.htm I think that you could push some epoxy in there also. Use the bearing packing technique, just keep pressing it in to the gap with your thumb. Use an epoxy with a long open time.

Those pistons indicate that somebody had plans for lots of valve lift and duration. The head and cam might be interesting.

You can still get some of them from the dealer (looks like 16 tooth is NLA from Courtesy though). Not sure how, exactly, to get the right part number, but they are out there. But you need to specify which transmission you're using. 4 speed, early 5 speed, late 5 speed? The early and lates use a different housing, but you can always just swap the plastic gear and shaft.. The last number is the tooth count. Here are some examples. Don't forget that the tooth count matches the rear diff ratio, not the transmission. http://www.courtesyparts.com/oe-nissan/3270258s18 http://www.courtesyparts.com/oe-nissan/3270258s17 http://www.courtesyparts.com/oe-nissan/3270258s19 http://www.courtesyparts.com/oe-nissan/3270258s16 http://www.nissanpartsdeal.com/parts/nissan-pinion-assy~32702-58s16.html I think those numbers are for the late 5 speed. These seem to be the early numbers. Looks like the 16 tooth is available for early, if the numbers are right. Short answer - the dealers still have access to a lot of old parts. http://czot.org/forum/showthread.php?1760-Speed-Pinion-Gear-and-Housing-Combinations-(-70-78-240-260-280Z) http://www.courtesyparts.com/oe-nissan/3270378100

Groovy. Looks familiar. Yours seems a little bulky compared to the factory piece. Is there nothing of lighter weight out there?

The year of car or transmission, does not matter to clutch parts. The clutch fork pivot ball is in the same location on all of the B type transmissions. The throwout bearing collar (the casting that carries the throwout bearing and has the ears that the clutch fork ride on) has to match the pressure plate. That's the most important thing. You shouldn't try to buy a clutch using year of car on these old vehicles. Know what size flywheel you have, and buy a clutch kit for that flywheel. The main reason to know your transmission is for the gear ratios and replacement parts. There are several combinations out there.

Nasty. And this all was happening while you owned and drove it? They used to work, and were slowly failing? The old PO trap. Scary. Makes me want to go do some preventive examination on my car.

The internet says they've always been the same - http://www.carpartsmanual.com/datsun/Z-1969-1978/steering/steering-column/28 Another thought, that's always bothered me a bit. There are/were several companies making polyurethane bushing replacements. There is a huge range of hardnesses possible with polyurethane, from goo to wood-hard. So one company's bushing could be hard and another's soft, but they're both polyurethane. Seems like even the hockey pucks come in two, practice and game. Really hard/difficult to compare.

Curb service? How did you get that? Market development?