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One-Family 1972 240Z Restoration (HLS30-93069)


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So here's a weird one from a couple of weekends ago:

I've been trying to get the timing right for a while now.  Points and distributor cap are new, points gapped correctly (I don't remember the exact number but I did it by the Haynes manual).

I put a dab of white-out on the pulley marks, started the car, let it warm up and then hooked up the inductive timing light.  No matter which way I twisted the distributor, I couldn't get the timing in range.  It was right on one of the end marks when the dist. was turned one way, and way off the marks when turned completely the other way.

Two weekends ago, I decided to check the cam sprocket for slack in the timing chain.  I've adjusted the rocker clearance before, but I'd never done the timing chain check.  So I pulled off the cam cover:


found a suitable screwdriver to block the timing chain, and looked at the marks.



and after:


I think that's enough right?

The weird thing is that the timing can now be adjusted within range.  I set it to 10 deg. BTDC and the car purred like a kitten with a rock-solid 700-rpm idle.  I wonder if it's correlation but not causation?  To my knowledge, there's no relationship between the cam timing and spark timing, since the dist. is run off the crankshaft...

The carbs have a good base tune, but the mixture still needs to be dialed in.  I wish the 14mm Colortune wasn't on backorder...  Ugh.


Edited by BoldUlysses
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21 hours ago, BoldUlysses said:

Hi guys.  I figured I should start a build thread in here.  The actual restoration is very close to being complete, but this seems like a good place to document a few things and perhaps ask little questions so I don't clutter up the main subforums with little inquiries when I can't find the answer.

Anyway, this is about 93069, which my dad bought new in October of 1972 from Cardinal Motors in Jacksonville, NC.  He was 21 years old at the time and just starting his senior year at NC State.  The car's block number is 118555 and it has a built date of 07/72 (right around the brake system crossover).  Original color: 901 Silver over red vinyl, dealer-installed factory air.

Here are a couple of pictures my dad took in November of 1972, one month after he bought it:



My dad had it repainted blue in the late '70s.  My mom has always liked blue cars, so it's possible she had a hand in choosing the color.  It seems rub strips were installed at that time also.

I obviously remember the car all growing up.  It was my dad's daily driver, and my brothers and I crammed into the back of it on more than one occasion, legs dangling behind the front seats, lying on our backs in under the hatch glass, watching the trees flick by overhead.  Very unsafe, but it was a different time.

The car deteriorated over the years.  Battery acid ate a hole in the inner fender well and firewall, water seeped down and rusted out the passenger side floor pan.  Rust started to pop up other places also, like the rocker panels and the trunk sill.  My dad had the engine rebuilt in the '90s, and the carbs refurbished by the original owner of ZTherapy around the same time.  I still have his "Just SU Carbs" and "240Z Tuneup" videos on VHS.  Pretty nice viewing.

I've always been into cars, but was never wild about the Z, which always felt weird because everyone I talked to said it was an incredibly cool car.  Maybe familiarity just breeds contempt (or indifference in this case)?  Who knows.  Regardless, I got into wrenching about 20 years ago and have had a long succession of project cars (FB RX-7s, mk3 Supra, Type 85 Audi, various BMWs, etc), but found it hard to muster the motivation to start restoring the Z.

Finally, about 10 years ago, I was at a point in my life where I had a place of my own with a 2-car garage and wanted to start bringing the Z back into focus.

This was its state then:

Screen Shot 2021-09-01 at 11.48.29 PM.png

Screen Shot 2021-09-01 at 11.48.13 PM.png

Pretty much a "barn find" in my parents' own garage.  Dusty, rusty, mismatched tires, etc.  I had chucked the bumper overriders years ago and managed to talk my dad into buying a set of slotted mags since he kept losing hubcaps.

It hadn't run in 6+ years at that point.  Back in 2005, I was driving it and the battery wasn't properly secured.  It slipped off the its pedestal and impacted the oil filter, creating a nice gash (and minor fire, which I beat out).  I was young and stupid and continued driving, trying to make it to the nearest auto parts store for a filter in spite of the fact that I likely had marginal oil pressure.  The moment the engine started acting funny I parked it and walked the remaining 1/2 mile to CarQuest for an oil filter.  I put it on and drove it home, but was scared that I had permanently damaged something, so I just let it sit.

Fast forward to 2011, Stage 1 of the restoration was determining if it would run properly or if the engine needed a rebuild.  I replaced all the consumables on the engine, had the carbs rebuilt (again) by ZTherapy and drained and resealed the fuel tank.  Got everything hooked back up and after a few hiccups...it started and ran just fine.  That was a relief.

Stage 2 had to wait a few more years.  I moved for work about 6 hours further away from my parents (they had been 1.5 hours away before), and took the Z with me.  In early 2014, I partially disassembled the car, removing the engine and some other key bits.  The next spurt of motivation came in 2016, when I finally got my garage organized and finished stripping the car down. 

In 2017, my dad came with a trailer and took the car back to his house to have the body restored.  He took it to a local body shop to have the rust repaired and the car repainted its original 901 Silver.  The body shop did an OK job.  I wish I had been local in order to supervise the work more closely, since they cut a few corners, especially in the engine bay.

Long story short, the car returned back to me for reassembly on Labor Day 2019.  I was initially pretty intimidated by the task at hand, but started chipping away at it and it started coming together.  I finally got it started again a little over a year ago so it could move under its own power to our new (local) home.

Since then, reassembly has continued in fits and starts, but this is where it stands now:


Still quite a lot to do, especially as regards the interior, but I've been pleased with the progress so far.  Thanks for reading and stay tuned.


So neat. I had a Silver 72, one of many 240z's I have owned. Looks beautiful.

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  • 7 months later...

So I'm getting back into Z work after taking a winter break to work on some house projects (pantry, painting, etc).

Discovered one of the rear brake lines was clogged, so I bought some tools and fabricated new ones:



Came out pretty well, I think.  The left rear still only bleeds in fits and starts, so if the braking performance still isn't there after a good bleed, I'll probably get the later S30 brake cylinder retrofit kit so I KNOW they're working.

Got the door cards back on this past weekend:




The pics don't show it, but they're actually pretty trashed, being 50 years old and made of glorified cardboard.  All new vapor barriers (I used the 3M sticky strips), clips and rubber receivers.  Little bumpers for the door release handles on order.  I'll need to re-chrome the piping as well.

* * * * * *

So I actually got the car out on the road for the first time since the restoration began.  I drove about 10 minutes down the road to the local O'Reilly's to pick up some fuel stabilizer, and stopped at the gas station on the way home.  Some impressions:

  • The car is pretty loud with the stock exhaust manifold and MSA exhaust (no resonator, just the muffler).  A little too loud, if I'm honest, but it does sound pretty good passing up through 3K rpm.
  • The car still needs a good tune.  Colortune on the way, and I'll need some advice about how to time it.  I have a points delete kit ready to install in the distributor.
  • It attracts a LOT of attention, and I feel REALLY self-conscious driving it (I'm not a high-profile guy).  It's really strange---I've never owned a car that stood out this much---and is going to take some getting used to.

One more exterior pic for good measure:




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  • 2 weeks later...

Colortune (finally) came in the mail yesterday.  So excited to try this thing; it's been on backorder for ages.



It occurred to me that given the above timing chain stretch adjustment, I probably need to do a fresh valve clearance check before I try to get the mixture really dialed in.  Time to break out the feeler gauges!

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  • 2 months later...

Quick update:  Haven't tried the Colortune yet BUT I was able to resolve the electrical/lighting issues I'd been struggling with for the past few months.

See resolution here:


I got the dash all buttoned up again, and drove the car around a bit with the now-operational brake lights and turn signals.  I even opened it up a bit on some of the back roads.  It sounds...quite nice in the 3-4K range.  I have a phone mount and plan to get some in-car videos soon.

In the meantime, here's another pic I took yesterday evening.  Needs a good bath.


Next goals:

  • Install PerTronix ignition parts
  • Final tune with Colortune
  • Install choke reinforcement bracket to center tunnel
  • Reassemble rest of interior (still missing HVAC + radio panel and center console
  • Purchase replacement choke knob (the elusive 1972 piece) and horn pad
  • Recondition the airbox
  • Etc etc
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Got the PerTronix points replacement installed.


Not super impressed with the quality, but it works.  Thread here:


* * * * * *

In related news, I've had issues getting the car timed correctly ever since I refreshed the engine, so I decided to ensure everything was aligned at TDC. 



This doesn't look right to me:


I think my oil pump might be a tooth off.  Going to drop it this weekend and see if I can get everything aligned properly.


Edited by BoldUlysses
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The oil pump was indeed 1 tooth off.  I wonder how long I'd been driving it around like that prior to the restoration?  I haven't touched the oil pump, but the engine was rebuilt in the '90s.  Maybe the builder messed up way back then?

Had to drop the front swaybar to access the oil pump.  Probably first time those bolts have come off in 50 years, so the threads smushed and cleanup was required:


Choke reinforcement bracket installed:


Interior is coming together:


Did some reconditioning work on the HVAC panel, but nothing to show yet.

I drove it around a bit.  I think the gas has gone bad.  There were several periods where it felt like the engine was working through a bad batch.  I put fuel stabilizer in there, but

  1. a good percentage of what's in the tank is 2 years old, and
  2. it's 93 octane but not ethanol-free.

So I'll probably drain the tank and feed that gas to my lawnmower and go get some ethanol-free 93 w/stabilizer.

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  • 2 weeks later...

Been chasing an issue that cropped up after the timing reset above.  The car intermittently seems like it drops one of the carbs and will barely run, before "waking up" again.  The idle is unstable as well, alternately bogging and racing.

I drained and refilled the tank with 93 octane w/stabilizer.

Timing is set to 17 degrees BTDC with the vacuum advance disconnected and capped.

Carb mixture screws are 2.5 turns down (baseline).

It feels like I have a vacuum leak, so I pulled off the carbs and IMs again to make sure everything is sealed up.


Going to buy another PCV valve to ensure it isn't that, and new balance tube gaskets are on the way (I had trouble sourcing them during the initial reassembly).

Nice clean mating surface:


We'll see where that gets me.

In other news, the interior is really coming together.  Got the new shift boot secured to the console and the new horn pad.  Pictures forthcoming.

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Looks to me like you are progressing nicely, and you're enjoying it.   Have the carbs ever been rebuilt?  While running, I think you can spray a bit of carb cleaner on the areas that can allow vacuum leaks (idle will drop if there is a leak is what I've heard).  Regarding one carb dropping out, you may want to check your fuel float levels if you haven't done so.  SU's are sensitive to that.   

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On 7/31/2022 at 9:46 AM, inline6 said:

Looks to me like you are progressing nicely, and you're enjoying it.   Have the carbs ever been rebuilt?  While running, I think you can spray a bit of carb cleaner on the areas that can allow vacuum leaks (idle will drop if there is a leak is what I've heard).  Regarding one carb dropping out, you may want to check your fuel float levels if you haven't done so.  SU's are sensitive to that.   

Yes, the carbs were rebuilt by ZTherapy back in 2011.  I tried the carb cleaner misting trick, but it didn't seem to reveal anything (the idle was hunting so much I'm not sure I would have been able to tell anyway).

Regardless, I got the intake all sealed up.  New PCV valve, fresh balance tube gaskets:


New steel exhaust manifold air injector plugs (w/high-temp thread sealant) to replace the ill-fitting brass ones I had in there previously.  Also gave all the manifold bolts a retorque.


I discovered some flakes in the rear carb line that must've gotten past the filter somehow, so I blew those out and checked the float and needle just to be sure.

The engine seems much happier now.  I sync'd the carbs and drove it around the neighborhood for a few minutes before it started raining.  Idle seems steady and acceleration is smooth.  I think it was a combination of a vacuum leak and potentially gunk in the carb line.  Going to keep testing.

Interior is coming together, though it's still got a long way to go.  The steering wheel and handbrake handle need to be refinished obviously, and the radio isn't installed, but I wanted to get it put together "all up" before I have to pull the dash again to install the new heater control valve and the blower motor.


Edited by BoldUlysses
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