How Far Can We Turn Back Time? A Near Total Restoration
 

The Car’s Background

I purchased the car soon after I moved to New Zealand. October of 2023, to be exact. Initial condition was good:

• 48,000 kms on the clock
• 2 owners in New Zealand. Both barely drove the car. Seemed like the previous owner was into trying to save modern classics.
• Paint had faded. Looked thin in places. Looked like the car spent a lot of time outside. This is common when importing the car from Japan.
• The interior plastics had become brittle and needed restoration. The seats had faded. The seatbelt holder strap things a bad mess.
• Everything was stock save for some HKS piping and an aftermarket igniter.

I thought it would be easy. But the road has been difficult (yet rewarding).

This thread will be the story of my rebuild.

First off, here are some baseline shots of the car as I received it.

https://cimg8.ibsrv.net/gimg/www.rx7...d0633ba94a.jpg
First off, here's the lead shot of the car from the previous owner.
https://cimg1.ibsrv.net/gimg/www.rx7...389472ef0e.jpg
The interior shot. Note how the seat belt retainer is coming loose. The ashtray is also bad and the map pocket on the driver (RHD) door is broken.

https://cimg6.ibsrv.net/gimg/www.rx7...7b43844d5d.jpg
The driver's vent louvre was broken. This part (like many) are no longer in production.
https://cimg5.ibsrv.net/gimg/www.rx7...7158ad341c.jpg
The passenger seat's seatbelt bracket was broken. The upholstery, sun bleached and tired.
https://cimg4.ibsrv.net/gimg/www.rx7...78cac8c013.jpg
Driver's side seatbelt loop thing is also broken and hangs off.
https://cimg3.ibsrv.net/gimg/www.rx7...c0ea13056b.jpg
Bits of plastic are broken and dirty. This is the clip that holds the hood prop rod.
https://cimg2.ibsrv.net/gimg/www.rx7...a632f14dd1.jpg
Wiper arms were all corroded. Note the cracked center dash vents and discolored plastic trim.

https://cimg0.ibsrv.net/gimg/www.rx7...f71e2bdb7.jpeg
The 13B-REW prior to restoration. Well...it's under there...

The Engine Bay
The car's engine was stock except for the HKS piping and an aftermarket igniter (I'll come back to this one later). Aside from being moderately dirty, the metal components were tarnished and dull. I took it to some rotary engine specialists in Tauranga. They gave it a clean bill of health. Called the car a rare find. They pointed out the aftermarket igniter and said: "can't speak to that".

Aside from a weird case of the car going to limp home mode once (which disappeared after I restarted the car), everything seemed to be fine. I called him about the car going to limp home mode. The boost gauge (the only aftermarket thing in the cockpit) was showing that the car was cutting boost anytime the throttle went down. After turning the car off for awhile and turning it back on, everything seemed normal. Couldn't replicate it again reliable to troubleshoot.

Maybe the aftermarket igniter was installed by the previous owner as a remedy. Either way, I had driven the car around to the shops and taken the wife for a little joy-ride or two. Everything seemed copacetic.

Where I Thought I Was
I had thought: great. I just had to find a few plastic bits. Replace the wiper arms. Clean the engine bay. Organize a respray. Detail the hell out of the car. Maybe swap the seats.

Little did I know that I was going to blow an apex seal a little over 48,000 kms.

Looks so minty already

Wow that thing needs TOTALLY restored.

Can't wait to see how this unfolds. Sub'd.

Ive never seen that upper steering column electronic dodad holder before. Is that from a company or custom built?

Nice clean car for the age.

Here's Where Things Take A Turn
A couple of weeks of having owned the car, I decided it was time to take it to the redline. After all, we all know what a redline a day means for rotaries. So I took the car to an open road and let the engine sing to 8000.
It was then that I felt...something. There was a bit of a jerk. And then the engine started feeling funny. There was a massive loss of power. Everything started to chug really badly. I nursed the car curbside.

Amidst all these passing cars honking at me giving me thumbs up for the car, my heart was in my my belly. That felt bad. And I didn't want to turn the car back on again. I called for a tow.

Green Brothers Racing in Tauranga took the engine apart for me and confirmed my worst fears:

• At 48,000kms, I had blown an apex seal.
• They needed to take the entire engine out
• It would take a long time to finish

And so, with the car engine bay getting gutted, I'm deciding to make lemons out of lemonade and, as completely as I can, redo the car's interior and bodywork. I've decided to have the engine rebuilt and reconditioned. I want to not only resurrect the 13B, I want to rebuild the entire engine bay so it looks as close to as it would have from the factory.

I want to turn back time.

But first...you guys wanna see what the engine looked like inside?


https://cimg9.ibsrv.net/gimg/www.rx7...72d9853473.jpg
2 rotors and 2 housings damaged. This triggered a full engine rebuild / recondition.
https://cimg7.ibsrv.net/gimg/www.rx7...11c84c3462.jpg
Here's the busted seal. I am told this was an older style multi-piece seal. The arrow points to where the apex seal actually broke. Such a tiny part.
https://cimg9.ibsrv.net/gimg/www.rx7...fc506975f7.jpg
Here's where the rotor apex broke
https://cimg1.ibsrv.net/gimg/www.rx7...db51b9e145.jpg
A small piece of apex seal went through the port and into rotor 2.
https://cimg3.ibsrv.net/gimg/www.rx7...e09c0b4260.jpg
Rotor 2 took damage from rotor 1's apex seal fragment

The doodad above the steering wheel is a period correct aftermarket boost controller. Mazda never added any kind of boost gauge on the FDs so getting a boost gauge of some form was critical. Think I forgot to point it out.

Great eyes!

What a 27 year old engine bay looks like
So if you scroll to the beginning, you guys will see what the car's exterior looks like. With the engine removed, these cars from the 90s feature get quite dirty inside and deep down.

https://cimg5.ibsrv.net/gimg/www.rx7...bdbf284069.jpg
Here's a shot of the engine bay as components like the air box and cooling are removed.

Neat stuff! Always glad to see someone attending to the smaller details and doing restoration type work, rather than just throwing as many mods as possible at it.

What killed the engine
It was almost inconceivable that I'd blow an apex seal with such a low mileage engine. It comes down to the aftermarket igniter. I was told that when I took the car near the redline, the racing igniter's timings didn't jive with the rest of my decidedly stock engine. Broke the apex seal, both rotors, and their housings. The only solution: rebuild the engine.

Where to go from here

• The engine is currently being rebuilt. Green Brothers Racing in Tauranga are taking it back to factory - fresh (with the most critical reliability modifications done).
• We are cleaning, reconditioning, and re-installing as many of the original parts as possible (including doing away with the racing
• This includes going back to the original igniter (which mercifully came with the car)
• That gives me several weeks / months to work on the rest of the car
• I was given many engine bits like the air box, hoses, connectors, and brackets - these I was tasked with cleaning and reconditioning
• The exposed metal bits of the engine would be vacuum blasted to improve their finish. Even bits like the alternator would be re-conditioned

The car's body

• The paint needed work anyway. And as we cleared the engine out, I realized that it's not a bad time to get the entire engine bay re-sprayed
• Why stop at the engine bay? I decided to have the whole car properly repainted
• Because we were going to be properly re-painting the vehicle, panels would come off allowing us to clean the actual core of the car
• All lights, reflectors, and lamps would be removed, cleaned, reconditioned, and re-installed
• A lot of trim was also going to be removed, cleaned, reconditioned, and re-installed

The car's interior

• Seats are coming out and getting re-upholstered.
• Every piece of interior trim is getting removed, cleaned, reconditioned, and reinstalled
• Broken pieces / worn pieces will be replaced with original Mazda parts.
• If no Mazda parts were available, I would source a good used component
• If needed, rare parts (like the louvres) would have to be repaired
• Even the connectors and various internal metal bits like clips would be reconditioned or replaced

https://cimg6.ibsrv.net/gimg/www.rx7...e9f558c915.jpg
Many 13B bits form this rat's nest of engine components to recondition and re-assemble

Time just gets things dirty.
What was amazing to me was how dirty things were underneath the detailed veneer of the car. Or maybe my car is just dirtier than the average FD. But after the engine bay got cleared out, I got a good look at what 25+ years of dirt, heat, and engine grime look like. It made me very curious about the dirt under the rest of the car and what condition the components were in would be like.

How clean can we get this thing? It seems like such a tall order, right now.

https://cimg0.ibsrv.net/gimg/www.rx7...8cc4f7f84.jpeg
The initial shot of the engine from the previous owner
https://cimg2.ibsrv.net/gimg/www.rx7...6cd97dcafb.jpg
My shot of the engine bay after things have been mostly cleared out.

Are you planning to do any reliability modifications that deviate from keeping it all stock, for example deleting the AST, or doing a catless downpipe? Maybe an upgraded Koyo Radiator or a slightly bigger than stock mounted intercooler?

This car should not have a Catted downpipe since it is JDM. I'm curious to know the direction too. Sounds like you want to keep stock or very close to stock.

The apex assist piece that broke its tip off must have been carbon locked in place.

When apex seal main piece expanded from heat of high rpm the assist piece could not slip down the side of apex seal to accomodate the apex seal expansion and the tip of the assist piece got wedged between the side housing and rotor housing.

Needed more daily redlining in its past or a good long decarbon soak before its sporty use.

I have never seen that apex assist piece break from detonation.

My strategy is to rebuild back to stock and do the reliability mods after. I always envisioned this car as a heritage vehicle. Something to pry away from my cold dead fingers when our grand kids are wafting around in soulless driverless cars. I guess I'm also trying to preserve a window to a '97 that isn't faded and dirt encrusted. I want to see how "untouched but reliable" I can make this one.

As for reliability mods, I would want to have the base ones done. Guess I want the AST before I delete it. The oil injectors aren't getting put in. I'm told I just have to pre-mix my fuel. Which is what I signed up for in the first place. I plan to drive the car. And to me, it would make sense to fit better cooling down the line - especially if I could revert to the stock component.

I think you guys have a lot more experience and a lot more know-how than me. So I've been getting very friendly with the search feature. I'm very open to advice and to your thoughts.

I feel like I learn something new everyday. I do agree that I was too hasty with the sporty use. A lot about what you said regarding the seal was echoed by the tech who was telling me about my car.

My understanding could have even been compromised because all I could think about at the time was "I blew up my engine".

Once rebuilt, definitely do agree that a good redlining is the solution :nod:

Any reason why you are ditching the factory OMP and injectors? Just simplicity? For a street car I tend to lean towards keeping that system intact and adding some premix but each have their own reasoning for keeping or ditching.

^Re: oil injectors - If you're running the OEM engine control unit (ECU), you've been given bad advice here. The OEM ECU cuts fuel on deceleration (e.g., closed throttle/engine braking from high RPM situations), so zero fuel injection = zero oil injection if you're only putting premix in the gas tank. You don't want to do this for reasons that should be pretty obvious. If you're running an aftermarket ECU, you can typically control whether or not fuel cut on deceleration is enabled, can't do that with the OEM ECU. So just keep the oil metering system intact & functional - you can always add a little premix lube to the gas for insurance.

Well, the engine is still getting rebuilt. So no decisions are set in concrete.

and like I said, you guys are the experts. I’m trying to learn by searching as much as I can. But there’s a lot of material.

Please keep the wisdom coming guys. I’m now trying to get more up to speed on the injectors.

FAQ has links to most of the good threads https://www.rx7club.com/3rd-generati...l-links-68640/

FYI, if you have, or have access to, a 3D printer, the seat belt retainers can be printed as I believe they are no longer available new.

https://www.printables.com/model/703...-belt-retainer

Car looks like already in great condition. Looking forward to seeing the progress.

What's Behind 27 Yr Old Door Cards?
 

Since the engine is out, it's time to make progress on rehabbing the car's interior. I needed a small victory to start the restoration. I wanted a closer look at the door interiors.
I love how easily door cards come off cars from this time period.

https://cimg3.ibsrv.net/gimg/www.rx7...9307121234.jpg
1997 RX7 FD with the seats and door cards removed.

I wanted to know what it looked like behind the door cards. The plastic door liner was held on by a black tar like gunk that had crustified. The plastic liner, dusty and aged.

https://cimg9.ibsrv.net/gimg/www.rx7...a59cd9d668.jpg
https://cimg0.ibsrv.net/gimg/www.rx7...6251e7ac7f.jpg
27 year old door liners in a vehicle with 48,000 kms.

I'm going to clean up the door interiors. I'll replace the door liners. De-gunking the black death tar will be a menace. Clean up components. Re-loom the wires. Also allow me to inspect what behind the door liners will look like. More pictures of what reversing 27 years worth of interior door grime looks like.

Small victories.

You don't have to remove the black butyl adhesive. Just heat it up with a heat gun and add fresh plastic.