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Project THESEUS: A '74 260z

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On 7/17/2020 at 10:07 AM, Noll said:


Thanks! I know nobody but me (and those reading this thread, I suppose) will know the difference, but I want to make sure to do it right the first time. I plan to keep this car for the long haul, and don't want to be thinking about the stuff I could have done better lol. Obviously there are many areas that are far from perfect, but it's all either the best of my ability at the time I did it, or stuff that I know I won't mind too much when I look back on it in the future.




Found a bunch of ZX parts for sale for the equivalent of 350USD. so I jumped on it, and towed it all home yesterday. 5spd, L28 f54/p79 with all wiring and accessories, and 4 matching wheels for that price seemed super good. Plan is to sell everything I don't need or want and ideally end up with an effectively free transmission that will be plug-and-play while I eventually get my 240sx trans bellhousing machined.

Ready for cleanup.


a lot of scrubbing later - not perfect, but good as it'll get without me taking all the ancillaries off.



This is where the bad started. Breaker bar on the crank wouldn't turn it, so I popped open the oil pan drain. The pan itself seems remarkably good, still has paint on it!


2.5 liters of terrible lay inside though. Intake and exhaust were not in an orientation where water could get in, so my guess is headgasket maybe? Engine seems to have been stored totally dry for 10+ years which is unfortunate.


Not the end of the world though, I got the lot for the 5spd, and anything else was a bonus. even if the block is a total boat anchor I can still sell stuff and with any luck end up with a free transmission for my trouble.

Speaking of, the trans took a bit of persuading, but came off without incident. Needs a good wire-wheeling and general cleanup, but shifts perfectly and seems in fine working condition as far as I can see.


The flywheel side, ehh, not so much.


Popped the valve cover off expecting the worst, and was pleasantly surprised. Surface rust on the cam from sitting, but otherwise pretty immaculate. Going to try to bathe the cam in white vinegar for a while to see if it can be revived maybe.



I'm assuming the crank and rods are total garbage, but I'll tear it all down anyway - maybe I got super lucky and it  just needs bearings and a polish. In any case, I havent' torn down a l-series yet, so it'll be a good opportunity to learn.


Don't tear it down yet. Lots of ATF in the bores like others have suggested (I used kerosene). If you can get it to turn, it may well run (albeit with a new cam, lol). Clean the sump out and check the bottom end. If it's not too nasty and turns, new oil fixes lots of things. Better you found all that water before you tried to turn it over.

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16 hours ago, slowlearner said:


Don't tear it down yet. Lots of ATF in the bores like others have suggested (I used kerosene). If you can get it to turn, it may well run (albeit with a new cam, lol). Clean the sump out and check the bottom end. If it's not too nasty and turns, new oil fixes lots of things. Better you found all that water before you tried to turn it over.


Solid points and a good plan. My only trepidation is that there seems to be some dirt or something sitting on some of the pistons (hard to tell), wouldn't want to turn the engine over and have it become grinding paste basically as it seems difficult to remove with the head on.. There's no rush to get this engine in the car even if I decide to go with it, so will take it slow and make sure not to damage anything else.




More welding today, as always.

Cleaned up the tension rod mount, and discovered a hole. Fixed this (no pic) and then welded on the new top layer I made:



And mocked up the other main frame rail section to go back on. Will need to make one more patch here as can be seen.



Just need to make that and a couple other small things and the new frame rail section can go on.

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If there is debris in there, tape a drink straw into a vacuum hose and shove the straw down in there to suck it out.

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17 hours ago, slowlearner said:

What you're seeing on the piston is probably carbon. As long as the plugs weren't rusty and bad, it's probably fine. Once you lift the head, you're going down another rabbit hole.

True enough, I want to make sure there's nothing loose in there regardless though. The plugs were, uh, not great:





15 hours ago, Lockleaf said:

If there is debris in there, tape a drink straw into a vacuum hose and shove the straw down in there to suck it out.


That's a very smart idea, thanks!





Took a gamble on some side mirrors, and it seems to have paid off. Wanted something simple and classic that fit the look of the car while not being stupid money or over-styled. Hard to say no to these for 33$ shipped, and the quality in-person is actually rather nice. Just need to glue the mirrors to the backing for security as they're just a press-fit with the rubber. 

Plus, I get to say I have Lada parts on the car - these are the same as what are OEM to my Niva, just black instead of chrome. Realized one day that the styling was perfect so ordered this pair.



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I think it was your lada build that led me to looking at niva mirrors as well.  They seem like a great looking option and often way cheaper than anything else out there worth having.  Very nice.

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1 minute ago, Lockleaf said:

I think it was your lada build that led me to looking at niva mirrors as well.  They seem like a great looking option and often way cheaper than anything else out there worth having.  Very nice.


Yeah, they seem to be way better than they have any right to be for the price, and have that timeless look.
I really need to get back to the Niva, just as soon as the Z is on the road and reliable.

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Finally got around to cleaning my pigsty of a workbench.


Properly bolted the taillights on for the first time and drilled the holes for the top trim clips:


It is super nice to know that the rear end is DONE.



A far cry from not that long ago:


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20 hours ago, Bleach said:



On 7/25/2020 at 4:05 AM, Draker said:

Wow! Good stuff.


Thanks guys! It doesn't always feel like I've done that much so it's good to look back once in a while and see how much has changed.





More progress towards getting the framerail on - made yet another patch and welded the middle section back on that I had cut off for repair access.


Probably going to redo the inner skin seam there, not at all happy with how visible it is. That patch visible in the background is also rather ugly (one of the first ones I did on the car), not sure how to go about fixing it now though as it's an awkward spot. Some filler and seam sealer should pretty it all up I suppose, it's structurally sound but ugly as-is.



super-rough mockup of the frame rail, with any luck I should have maybe one more small patch to put in on the car before it can go on!


And my next task once the frame rail is on, re-building the lower rad support.


Edited by Noll
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Frame rail welded on today, and cleaned up:




Patches on patches on patches:


Welded in this patch for the inner skin, and made it all nice:



Cleaned up the worst of the damage on the lower rad support - outer sections will be replaced obviously.


And cleaned up the upper rad support and threw it all on for mockup.




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Made and welded in the inner skin section for the awkward-shaped bit by the firewall:


Fixed up the subframe mount pockets:


Started to patch the lower rad support and mocked it up again to make sure I wasn't messing anything up.


and verified that the tow hooks actually bolt in to the new captive nut plates I made:


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 Fixed the lower crossmemember:


Welded on:



And mocked the upper section up again. Next up will be the inner wheel arch skins.



Edited by Noll
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Got to work building the inner skin for the driver's side today.

Mocked up:


The void to fill:


And welded up.



If you get the angle right, it almost looks like it's done. I'll be doing the front-most bit in a couple different sections due to having curves, didn't want to bite off more than I could chew by trying to do it all as one panel.



I ran out of welding wire when I was on to the last seam to do, and was annoyed until I remembered the welder came with some little "sampler" spools when I purchased it. Not the best mounting method, but it let me get the job done today.


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Finished the main lower skin rebuilding on the driver's side today. Some small things still to do, but overall very happy with it:




Still need to deal with all the spotweld holes and make a plate with weldnuts for the 240z bumpers to mount to. happily, the 260z sheetmetal retained the holes for the bolts (just not the nuts), so I don't have to mock the whole front end up to find the correct positioning for the mounts.


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The passenger side inner structure has rusted through in a couple spots, so I decided to pull apart the driver's side to make sure it wasn't also rusting through from the inside. It was, but just pitting, all cleaned up now.




While I was at it I spent an hour straightening out the old accident damage from the sheetmetal - not sure how much the 'before' photo shows it, but it was SUPER wavy and the upper flange where the fender bolts on wasn't in great shape either. It's not perfect, but the majority of the remaining damage is behind where the rad support will weld on so no big deal.



Need to do the same on the passenger side, along with more rust repair, but going to wait until I've welded on the inner skin first for some extra strength.


Also threw on the front fender, nice to see it looking somewhat whole again. It's sitting high because of the temporary brace, but close enough.


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Someone was kind enough to send me a free pair of the top portion of the strut tubes to replace my stuck gland nuts, and they showed up yesterday.


Cut the top 2" off the struts, being careful to not cut the inserts so they were easy to remove. One side went fine, but the other was a MASSIVE pain due to the insert rusting to the tube. Ended up having to cut it in half, drill a hole in the bottom of the strut, and hammer both sections out. This sucked, but I got it done eventually.

Mocked up ready to weld back together:



Welded back together using the other old insert to keep things straight, and welded the lower spring perches on.


All mocked up and looking good. need to take 1.5" out of the main tube section then I can weld it all back together for good. Need to figure out some way to clean the insides of the tubes out - the old dented insert fits just fine but the new ones are not wanting to slide in cleanly because of the leftover rust flakes.


I have these leftover from the "new" top sections so for a bit of peace of mind and extra strength I'll cut one in half and weld it over the lower cut/weld after cleaning it up, and do the same on the other side so the struts look the same.


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Got the front struts nearly done today.

welded up the hole I had to make for chisel access:


Cut up some leftover bits and made them into a brace over where I had to cut/weld the one strut:


Shortened and welded the upper sections (put a proper bevel in both parts before welding). I see everyone using a pipe cutter for this, but I just scribed a line with my digital calipers and used my angle grinder to cut on one side of it. Worked a treat.



Cleaned and primed:


And painted. Once it cures I'll put the sleeves back on and then get to cleaning out the interior bores enough for the new inserts to fit. (paint imperfection on the right one fixed after pic).



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Got everything as assembled as it can be until I get the inside of the strut tubes cleaned out, loctited the coilover sleeve clamp screws to make sure they don't work loose. On to more engine bay rust work next, and the rear struts at some point.


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Started taking apart the rear suspension today. Apparently I am the luckiest person alive because both pins came out in under 20 minutes total with just a hammer and punch.


Heck, the one in the left is even reusable, which after shipping and import costs probably saves me 80-100$. Was NOT expecting it to be this easy given the horror stories I've heard about the pins and how rusty my car was (plus the fact that it sat outside for ~20 years before I got it). The one on the right had some corrosion and the threads were FUBAR, but after welding on a nut and using my impact to spin it in its bore for a minute to break it free it also tapped right out like nothing.


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That's really cool. Thank God for small mercies. I know how many times I've wondered at how easily thing came apart. Make sure you put a coat of anti-seize or penetrant on those bolts when you torque them up again. 😉 

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On 8/22/2020 at 10:51 PM, Noll said:

Apparently I am the luckiest person alive because both pins came out in under 20 minutes total with just a hammer and punch.

Horror story spindle pin removal is a right of passage for 240z ownership, maybe the car felt you had already paid your dues bringing her back and decided to take it easy on you for a change.

I got your fasteners and hardware back from the platers today, I should have it in the mail by tomorrow.


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Yep, I'm still at a bit of a loss as to how I got so lucky, but I sure won't complain!


Grannyknot, package just arrived today, many thanks! Awesome to have non-rusty bits again without spending mega money on NOS stuff.





Ok, I have a bit of an issue and could use some pointers from anyone who has been here before in regards to suspension.

I can't for the life of me get the KYB MR2 inserts to fit into my housings.

A few old threads mention the MR2 inserts as being a "tight fit" but this is absurd. The 240z fronts I'll be using for the rear fit fine (other than obviously being too long now) - they measure ~42.8mm in diameter whereas the KYB MR2 inserts measure ~43.8mm dia. - even with the 240z inserts having a little bit of play there's not enough extra space for the extra 1mm. I've used a small engine cylinder hone tool to clean up the inside of the tubes just in case there was rust buildup causing issues, but to no avail. In theory I could keep going to remove the extra ~.3 or .4mm I need for the KYB MR2 fronts to fit, but that will take forever and removing material from strut housings doesn't scream "good idea" even if it's minor.

I also removed the paint off one of the struts to test, but even with that there's still no way it'll fit.

I initially went with the 87-89 KYB MR2 fronts because the Tokico BZ3099's the everyone seems to recommend in old forum threads are very much NLA, and as the KYBs are for the exact same car I figured they would work fine from a dimension standpoint.
As you can see here though, the bottom few inches is the "correct" diameter before it steps up for some reason. The 3099's have no such feature.


At this point it seems like I have a few options.

#1 - Monroe MR2 rear inserts

These don't seem to have the "step" that the KYBs have, although it's a crapshoot as to what the actual diameter is. The specs page also leads me to think the body length could be a tad long (even though they're for the same application as the KYBs?), and, I dunno, Munroe seems like super cheap daily-beater replacement stuff, not sure if they'll be up to snuff for the coilover setup?

#2 - 85-86 KYB MR2 inserts

These seem close in specs (a tad longer in stroke, not sure about body though), and a few old forum threads mention they're a bit narrower although not by how much. Visually they look more"right", and I can always shave down the bottom cone seat if they are a bit too long for my shortened housings.

#3 - VW rabbit or 300zx etc shocks

Alternatively, I could do some more searching through old forum threads and dig up some other options (and then compare specs to suit). Too short is fine as long as the stroke is long enough still, I can always make a spacer for the housing. Nobody seems to list diameters though, so still a bit of luck as to if they'll be a tad too large in that aspect still.

As it stands currently, #2 seems like the best, as they seem the most likely to fit and if they're too tall I can always shave the bottom cones or just return them if the difference is too great. Any other options/thoughts? I guess I could also go for Konis etc, but that's $$$$ I can't really justify spending just yet

Edited by Noll
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