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Posts filed under ‘240Z Restoration’

Datsun 240Z Restoration: Little Things

January 16, 2012 by Matt

Datsun 240Z ID Plate VIN Block Number Matching

A few notes from the last month or so of having the Z home:

  • I bought How to Rebuild Your Nissan/Datsun OHC Engine last week as a sort of early birthday present for myself. Its purchase completes my acquisition of the “trilogy” of glossy Datsun Z-Car books. The other two books are How to Modify Your Nissan/Datsun OHC Engine (lots of naturally-aspirated race-prep stuff; very little on turbocharging) and How to Restore Your Datsun Z-Car (an absolute gold mine for the would-be restorer, with step-by-step instruction on teardown and reassembly, parts diagrams and loads of photographs). Gotta get a set of the factory shop manuals next.
  • The battery is removed from the car, but last night, in a kind of experiment, I hooked up my battery charger to the leads, turned the knob to “low charge” (5A or so) and turned the car on. Everything was as weak, as you’d expect from say, a dying battery, but it did something for me to be able to turn on the hazards, illuminate the lights and fiddle with the (original!) radio. Sometimes you just need to see a sign of life, you know? First time that’d been done in 8 years.

Datsun 240Z ID VIN Block Number Matching

  • I’ve been trying to determine whether or not the Z’s engine is original. Its status that way will have a big impact on how I go about restoring and/or upgrading the car. If it’s original, then I’d like to keep it original, which makes upgrading a bit more difficult (overboring the block from 2.4 to 2.8 liters isn’t quite as easy as I had thought it might be). If it’s a replacement engine, then all bets are off and, rather than rebuild it, I can swap it out for an engine that was 2.8l from the factory, the L28. So, how to establish the engine’s credentials? There’s an ID plaque (shown at top) affixed to the passenger side strut tower in the engine bay with the VIN and engine block number stamped on it. I hadn’t noticed it until now because when the Z was repainted in the late ’70s, the engine bay was blacked out and the ID plaque painted over. So, last night, I located the engine number on the block, shown above: 118555. I then removed the voltage regulator, allowing me to access and remove the ID plaque. I scraped as much paint off it as I was willing to last night (will eventually do the whole thing), but enough for me to read the block number listed: 110555. I’m almost positive it’s just a typo, but plan to ask those more familiar with these things for their take on the matter.

Editor’s note: This post is Part 6 of an ongoing series chronicling my efforts toward the restoration of my 1972 Datsun 240Z, originally my father’s. Read the other installments here:

Update (01/16 9:01 PM): Received some information about the VIN/ID plate numbers mismatch from a knowledgeable gentleman on one of the Z forums:

Looks to me like you have a mis-stamped service block.
The numbers don’t have the familiar “cursive” bent normally associated with Nissan OEM Stamps.

See the “L24?” The scripted numbers for the engine block should be similar, with the top section of the “8” looking somewhat like an onion with the green chopped off, if that makes any sense, along with the bottom section of the “5” being a bit more “open” and not a “reverse C” configuration.

I have never seen a mismatched plate/engine from Nissan, ever.

My surmise would be that you have a “service block” which arrived with no serial number in it, and generally the dealers left that blank when they installed it.

Looks like someone sometime got a letter-number stamp and just put the numbers on your block.

And they mucked it up.

Having a service Block in with no serial number arguably can be said to have a “Factory Service-Replacement Nissan Engine” and wouldn’t necessarily be knocked down for not having an “original” engine. (Some Z owners blew their ’70s engines at autox and got replacement engines from Nissan under warranty! What happened to those days GT-R tranny owners?)

Unfortunately, what you have is most definitely not “matching numbers,” but if you had service history to show the swap/change you could argue the accident like you theorize.

I’m querying my dad (the Z’s original owner) to hopefully get more of the story, if there is more to it. I just wanna know, you know?

8 Comments on Datsun 240Z Restoration: Little Things

Datsun 240Z Restoration: Coming Home

December 17, 2011 by Matt

Datsun 240Z Blue on Trailer

After many years of anticipation, HLS30-93069 finally made the 90-mile trek to its new home yesterday. As shown above, I loaded it onto a car carrier and borrowed my dad’s truck for the event. Naturally, it poured down rain the whole drive. Completely dry before and after, of course. I was more than a little frustrated with that turn of events given that it was moisture that caused the bulk of the 240Z’s current issues.

1972 72 Datsun 240Z Blue Garage

I waited until this morning to enlist my brother-in-law’s help in rolling it off the car carrier and into the garage. Fortunately, 2350 lbs or so isn’t a whole lot of car to push around, so I don’t foresee any issues rolling it in and out of its spot by myself when the need arises.

1972 72 Datsun 240Z Blue Garage

In the garage, still drying off. One of the prerequisites to actually digging into the restoration is building storage shelves and racks around the perimeter of the garage. We need space for the bits that get removed from the Z as well as general storage for the house itself.

1972 72 Datsun 240Z Garage Yellow Car Cover

After a gentle bath to remove whatever remained of 8 years of dust the rainstorm didn’t wash off last night, the Z was tucked in under an old car cover. Truth be told, it’s more there to protect my family from the car’s disintegrating rubber bumper strips than to shield the car from inadvertent kid scratches.

1972 72 Datsun 240Z Blue L24 L-24 Inline 6 Six Engine Motor

Cleaned up the engine bay a bit and reinstalled the factory orange air cleaner. Interesting Z tidbit: According to a reputable SU carb expert, the simple sheet metal air horns built into the inside of the air cleaner box flow somewhat better than any aftermarket units. Many early Z owners install non-factory air horns in pursuit of a looks and performance upgrade, but for the latter, there’s really nothing better than the orange OEM piece.

1972 72 Datsun 240Z Battery Tray Rust Rusted Out

A shot of the cause of many of the car’s issues: A rusted-out inner fender directly beneath the battery tray, up against the firewall. Driving the car in the rain, water has a direct path through the fender and firewall, down into the passenger floor pan.

I also completely removed any vestiges of the ill-advised electric fan conversion and its associated wiring, and drained the oil. The oil looked clean—there were no metallic flakes at all, but I doubt that’s conclusive as I’m sure I changed the oil immediately following the engine fire incident. I racked my brain trying to remember if there were any visible particulates in the oil then, but for the life of me I can’t recall. In any case, the engine’s coming out and going to be torn down and checked. At least it’s home. Feels good to have the Z where it belongs.

Editor’s note: This post is Part 5 of an ongoing series chronicling my efforts toward the restoration of my 1972 Datsun 240Z, originally my father’s. Read the other installments here:

7 Comments on Datsun 240Z Restoration: Coming Home

Datsun 240Z Restoration: The Rollout

November 26, 2011 by Matt

1972 Datsun 240Z Blue

Took advantage of the opportunity afforded by being at my parents’ place for Thanksgiving to discuss the situation with my dad, and to roll the car out of the garage for a bit. It’s the first time the car’s been moved in several years, and I was shocked the rear drums weren’t rusted solid, having left the parking brake engaged. We did have to put some air in a couple of the tires, and we couldn’t find the key, so the steering locked, preventing the car from being rolled out farther. But it was still nice to get a gander at the whole thing.

1972 Datsun 240Z Blue

As mentioned, I did have a chance to “unburden” myself to my dad regarding the hopelessness of being able to give the car a thorough restoration on our family budget, and was genuinely surprised when he half-floated the idea of “sponsoring” a restoration provided I do all the grunt work—which I’m more than willing and able to do—and manage the project in general. The extent of his involvement will be clarified going forward, but knowing my dad and his connection to the car, I’m fairly certain he’ll want to be involved in some capacity.

The upshot is that the Z is going to be taking up residence in its new home here within the next two or three weeks, at which point I’ll carefully develop a game plan and start tearing into it. One of the slight deviations from my “full restoration fantasy” is that certain wish-list items, like a 5-speed, disc brakes or a 2.8l bore-out (if even possible) are going to have to wait. The focus will be the body and interior, along with restoring the engine, suspension and driveline to fully-operational condition. I would, however, like to add two things in the process of bringing the car back from its current state: Headers and a full exhaust, and an air dam. Everything else can wait, and be added later. At this point, after having owned the car for 10 years, I’m just eager to see the process move forward. Wish us luck!

Editor’s note: This post is Part 4 of an ongoing series chronicling my efforts toward the restoration of my 1972 Datsun 240Z, originally my father’s. Read the other installments here:

2 Comments on Datsun 240Z Restoration: The Rollout

Datsun 240Z Restoration:
Confessions of a Poor Car Enthusiast

November 23, 2011 by Matt

901 Silver Datsun 240Z 240-Z HLS30 S30 Nissan

I finally figured it out. After two and a half years—maybe longer—I discovered the missing piece of the existential puzzle that is my “car promiscuity.”

Since acquiring my driver’s license in ’95, I’ve been through a lot of cars. But more recently, since mid-’09, I’ve made a series of car swaps I couldn’t really justify. Obviously, my automotive flexibility as a husband, dad and homeowner is radically more constrained than it was when I was single, child-less and renting. That said, ever since my car interest “reopened” in mid-’09, I’ve felt this sort of restlessness, discontent, some kind of inexorable force pulling me from one car to the next, searching for what I knew not.

Let me explain our family’s car arrangement. We had established a while ago that there were three “slots” for cars to fill: The family hauler, the daily driver and the project car. The minivan has filled the first slot; no real drama there. The project car slot has been occupied, since late ’01, by my Datsun 240Z. The daily driver slot, in contrast, has seen a remarkable amount of turmoil and turnover. Starting in mid-’09, I’ve been through a ’93 Volvo 940 Turbo, an ’01 VW Jetta TDI, an ’86 BMW 635CSi, a ’95 BMW 525i and I had been searching for its successor. There were a veneer of practical reasons justifying the move from one to the next, but the undercurrent was the aforementioned, irrational restlessness. And it drove me up a wall. It upset my parents. It upset my wife. Why did lose interest in my current daily driver so readily and feel compelled to jump ship? What was I looking for?

The key lay with the third slot, the project car. As a car buff, I love to tinker with cars; there’s little I’d rather do than be working on them. My 240Z is in need of a full down-to-the-metal restoration, and I finally have the space in my new garage to begin the project. So what’s the problem? It’s the realization I came to earlier tonight, and it ties everything together: I will never have enough money to restore the 240Z.

I just won’t. Not the right way, at least, the way it needs to be. Between two young kids, the demands of the house and my line of work, without going into exhaustive detail, the money simply won’t be available for at least another 15 years, if ever. The realization should have been obvious, and I’m sure it was present subconsciously, but tonight was the first time it bubbled to the conscious surface and I “let myself” say it.

And knowing that, deep down, was what drove me (pun intended) from one daily driver to the next. Bereft of a long-term car project I could realistically hope to complete, I gravitated toward short-term “easy power” from my daily drivers. I wanted something that could satisfy my need to get grease under my fingernails, start for me every morning, and haul the family around if the need arose. I didn’t want to admit to myself that the 240Z project was an albatross, but the emotional needs of my hobby would not be denied, and redirected themselves toward my daily driver, creating overlap, cognitive dissonance and great frustration.

It’s difficult to overstate the magnitude of this realization. I feel like a weight has been lifted. It brings so much of my automotive angst over the past two years into focus. My mindset vis-a-vis my car interests going forward is so much more clear.

Editor’s note: This post is Part 3 of an ongoing series chronicling my efforts toward the restoration of my 1972 Datsun 240Z, originally my father’s. Read the other installments here:

3 Comments on Datsun 240Z Restoration:
Confessions of a Poor Car Enthusiast

Datsun 240Z Restoration:
Opening the Tomb

August 27, 2011 by Matt

1972 Datsun 240Z

I promised myself I’d take more pictures. During a visit to my parents’ today, I did.

Behold, my project car, a 1972 Datsun 240Z. My dad bought it new in ’72, and gave me the keys as a college graduation present. As outlined in my previous post, it has issues, some significant, but notwithstanding those I’m eager to dig into the restoration.

1972 Datsun 240Z Interior

It hasn’t moved under its own power since March 11, 2004. That was the date of the minor engine fire and subsequent operation without oil pressure for several minutes. Since then, it’s been parked in my parents’ garage, awaiting the day when I would have a garage of my own to transfer it to. That day has come, but its new home isn’t quite ready yet—some organization is still required. So it’s still gathering dust, 90 minutes away.

1972 Datsun 240Z Rusted Out Passenger Floorpan

Here’s the major issue: Rust has completely consumed the passenger side floor pan and frame rail underneath. The driver’s side is fine, so why did its counterpart fare so poorly? Simple: The battery tray is smack up against the firewall on the passenger side of the car. Over the years, uncleaned battery acid ate a hole in the tray, the inner fender beneath, and the firewall itself. With all those panels swiss-cheesed, rainwater had a more-or-less direct path through the firewall and down into the floor pan, where it sat and oxidized the metal. It looks awful; I know, but again, my only hope is that I’ve seen Z-car floor pans and frame rails restored from even worse states of decay.

1972 Datsun 240Z Engine Bay L24

The L24, a 2.4l SOHC inline-6. Lovely engine. The orange, oval air cleaner assembly is in the trunk at the moment. You can see a few of the “modifications” I made prior to the car’s stasis: Air pump removed, air injection system capped off and other emissions garbage pulled from the balance tube, and an electric fan (stupidly) added to replace the stocker, whose fan clutch had seized. The carbs were rebuilt by ZTherapy in the late ’90s and have the ball bearing throttle shafts. Overall, the engine cleans up well. I just need to tear it down and inspect the internals as a matter of course.

All in good time.

Editor’s note: This post is Part 2 of an ongoing series chronicling my efforts toward the restoration of my 1972 Datsun 240Z, originally my father’s. Read the other installments here:

10 Comments on Datsun 240Z Restoration:
Opening the Tomb

Datsun 240Z Restoration:
Projecting Forward

August 7, 2011 by Matt

1972 Datsun 240Z in garage

Here’s the situation. I own three cars: my BMW daily driver, the family workhorse minivan and my project car, pictured above (it’s the only picture I presently have). It’s a 1972 Datsun 240Z. And it resides in my parents’ garage, 90 minutes away.

Here are the facts about it:

  • My dad bought it new in ’72, and gave me the keys as a college graduation present in late ’01. It’s something of a family heirloom, so selling it is out of the question.
  • Part of the reason he gave me the keys was that I enjoyed working on it so much. Before the passing of the baton, I’d taught myself to rebuild and synchronize the twin SU carburetors, adjust the valve clearances, and do a full tuneup. I’d replaced both the brake and clutch master cylinders as well as the rear drum brake cylinders, and removed the ancient and inoperative dealer-installed A/C system. I love tinkering with the old 2.4l SOHC inline-6, and the car’s electrical system wiring diagram spans, in its entirety, a whopping two pages—meaning the car’s electrical system is admirably simple to diagnose and fix. And not made by Lucas.
  • The car needs a full down-to-the-metal restoration. The passenger side floor pan is rusted through, the battery tray is eaten away, the firewall has holes in it, and I can push my finger through what’s left of the rocker panels. It’s pretty far gone, and my only reason to think the car isn’t destined for the scrap heap is the fact that I’ve seen 240Zs completely restored from being even farther gone than mine is. The body style was popular in its day, had a long 8-year model run, and replacement panels are readily available. And I have faith in miracle-working powers of good body men.
  • The engine quite possibly needs an overhaul, if not total rebuild. Some years ago, due to a combination of circumstances, I ran the engine with zero oil pressure for about 3-4 minutes, and it’s never been quite the same since. If nothing else, it probably needs the mains replaced and cylinder bores honed. Of course, none of this is terribly difficult with the engine out of the car, which it will be during the body’s restoration.

So here’s the question: In addition to restoring it, what should I do with it? There are a number of possibilities:

  1. Keep it as stock as possible. Given that, as noted above, the car is something of an heirloom, there’s a certain appeal in leaving the car “numbers matching,” or at least ensuring the body’s and engine block’s serial numbers match up, even if I do install some aftermarket bits like headers or uprated suspension and wheels.
  2. Install an L28 (2.8l iteration of the 240Z’s engine) with either triple Weber carbs, or keeping the stock SUs. Click here to view an example of that combination in action. The power bump over the L24 would be healthy, and the setup wouldn’t have the complexity of a turbo, but would have the downside that the engine wouldn’t be original to the car.
  3. Drop in and tune an L28ET, the factory turbocharged version of the Datsun/Nissan L-series engine. Here’s an excellent video of that setup. It’s a fairly straightforward swap; the motor mounts and drivetrain bits match up, the only custom fabrication required would be the engine management and peripherals like the exhaust and intake piping.
  4. Go nuts and install a completely different engine, like a small-block Chevy V8, SR20DET (Nissan 4-cylinder turbo), RB25DET (Nissan 6-cylinder turbo), 1JZ-GTE (Toyota 6-cylinder turbo) or Mazda rotary (not sure if this has ever been done). Advantages include the cool/interest factor and power potential; challenges are legion and include just about everything you can imagine, from sourcing an engine in the first place to all the custom adaptation required.

Any thoughts? I’m leaning toward Project Path No.1, but the lure of boost is difficult to resist. Whatever the case, when the car finally arrives and I begin tearing into it, barring any “unforeseen acquisitions,” the Z will officially be the first Project Car™. Stay tuned.

Editor’s note: This post is Part 1 of an ongoing series chronicling my efforts toward the restoration of my 1972 Datsun 240Z, originally my father’s. Read the other installments here:

9 Comments on Datsun 240Z Restoration:
Projecting Forward