So, it's been awhile. Decided to start a new build thread in hopes of holding myself accountable for continued updates. Since the last time I was posting on my previous build thread...

Sent car to Curly and AR. Found out engine was blown in the first couple hundred miles by crap work/tune by the previous shop. Curly did wonders on fixing lots of problems in the car. Moved to the Netherlands, got the car shipped over. Tried to register, but ran into various problems. Decided there was only one possible answer: Get an already imported North American NA that is largely exempt from the requirements for an imported car, swap in all NB interior/electronics/drivetrain with the NA exterior.

Stripped out everything of the NB that I wanted, got a shop to cart off the carcass. Started to strip the NA, but then discovered more things I didn't like. Chatted with Curly, decided to replace everything with a modernized ignition/wire in Link ECU/more that I'll address in time.

Begun to strip the NA chassis, found rust:



But then, as I started to dig into it, I started finding rust everywhere, and even worse, I gave a slight tug to a brakeline and it immediately broke. Red alert!


So, that leads us to current day, where I decided there is only one possible solution. Strip everything, unintentionally shave the engine bay, and restart from scratch. After a massive round of completely stripping the interior and steam cleaning all the nasties, I've ground out the rust and replaced most of the questionable areas with POR15 (Pardon the mess, but the mess isn't important, POR15ing all of the rusty areas is). I've got one spot still to get:


Spent a couple days removing everything in the engine bay and angle grinding. I'm going to be hitting it harder throughout this week, in the end, I'm going to be doing a complete engine bay shave with a full custom from-scratch wiring situation because I can't stand how crap the harness and wiring is. Eagle eyed viewers will see still more rust in the picture.


So, what am I doing right now? From the previous picture, by the end of the week, I hope to have the entire engine bay shaved and POR15'd + enamel painted. I am currently considering the idea of stripping the entire undercarriage, as I ended up removing a large chunk of the undercarriage protection from steam cleaning when I tried to remove the gunk. Powerwashing is ineffective against the gunk. If I do, I'll POR15 the whole undercarriage and then use por's rubberized undercoating. I know, undercoating is supposed to be bad on Miata's...but not when it's going on top of properly applied POR15. That stuff is damn near invincible on the undercarriage from previous experience with Miata's.

 

As a man currently fighting a rust battle on a feral FD rx7, I've got some insight and ideas.

In the last few months I've spent way too much time reading about rust eaters, converters, and inhibitors. I think the only downside I read about por15 is that it has a tendency to peel off if applied to anything other than rust/raw metal - but the way you are applying it looks right. Just over the rusted and raw metal areas.

I went with a combo of wire wheel (on a angle grinder mostly, some drill in harder to reach areas) Ospho converter (just an acid that turns the rust black / converts it), and raptor liner corrosion inhibiting primer / raptor liner for the undercoat.

The raptor liner is super hard and durable stuff, I'd personally stay away from any rubberized undercoating that's often what causes the corrosion. Raptorliner scored VERY high in a lot of the corrosion resistance comparison / test videos I watched
Personally after using it it's tough stuff, you can't scratch it even if you tried with a screwdriver, and adheres VERY well (no peelage). And when used with their primer lasted longer than almost anything else in their corrosion bath test.

Also equally important is that you use some kind of corrosion inhibitors in the cavities. I went with a lanolin based water wicking solution with fluid film and their fogging 360* nozzle to fill all the frame rails, cavities, and other areas I couldn't get to to wire wheel and properly seal with primer and raptorliner. These penetrating oils wick all water away, and keep moisture and air from reaching the metal which basically stops any rust happening inside the rails/cavities in its tracks. Inside a cavity the stuff should last basically forever, but on my FD I'll probably re apply every 5 years or something (even though I live in the desert).

Keep us posted! The car doesn't look that bad so you can definitely save it. Just cut out all the bad rust spots and treat the rest.

 

Read through your thread, @Fireindc , and for what it's worth, I'd buy that FD in a heartbeat.

Regarding Por15, it's key to understanding how it works. Think of it like a glue, and it requires sufficient "grip" to properly cure. Most people aren't willing to really scratch up a painted surface to get to a point where Por15 can properly cure. Regarding what my plan of attack is, I'll be doing something similar to you. I decided earlier today to go with POR15 + Engine Enamel'ing the entire engine bay. The entire undercoated area, including the arms, will be getting Por15 + Por15 BedLiner. In the wheel wells where it matters, I'll be spraying some Por undercoating on top of the bed liner for extra protection. There will be no impact with the rubberized undercoating at that point.

Could you throw me a link to that lanolin product? I'd be interested in getting some just for ease of mind. One thing I dislike about these cars is how hard it is to deal with the cavities. I'm debating buying a welder and going wild with this car, but it's been many years since I welded last. However, I am extremely confident that if I get to that point where I buy a welder and start opening up cavities, properly applied Por15+Bed Liner will last the lifetime of the car.

 

I'm using fluid film with the applicator wand:
You can drill a small hole, feed the wand in, spray the area, and pull it out and plug the hole if access is a problem. I did a lot of research and settled on this method, as even using a paint or converter in the cavities might not stop the rust. The penetrating oil "creeps" and spreads into the cracks, even will creep upwards (against gravity), so once you flood your frame rails with this stuff you should be good.

I agree about the por15, and it looks like you are using it correctly. I haven't looked at their bedline product but it sounds pretty similar to the rapor liner primer + bedliner I'm using, and that **** is bulletproof.

 

Thanks for the tip! Picked some up for myself, it certainly seems like it will do what I want with the cavities without having to go crazy.

 

oof, rust is such a pain. good luck with the repairs!

 

So, an update.




I'm somewhat confident, and I tried to make the situation as visible as I could, that there's been some front end damage on this car. I'm not overly happy, as I was told the car was accident free. But that would be fine, except for...



This rust hole just looked like a tiny bit of rust peeking through the paint. Once I chased it down, I'm now stuck figuring out how the hell to patch this up now that it's back to good metal. I may cut out more and just make a circle of it, then weld (I'll have to get a welder, and it's been years, but...), although I'd prefer other options considering the complexity of the location. Looking closely at the picture, I may also not be done with the grinding. Either way, this is a pain in the *** to find.



I've mostly ground out the rust, but this was all hiding beneath the paint. This is one of the reasons I suspect the front end damage, you don't get rust under undamaged paint if everything is OEM like this.



Although I've ground out most of the rust, some should still be visible. This is another spot where it was rusted underneath the paint and if I had not stripped the paint, I'd have left the rust there. This is abnormal, and isn't a good sign for this car.

Unfortunately, the accident-free "perfect" car, based on just what I've seen in the engine bay, isn't. What's worse, I strongly suspect shoddy repairs in the past, which while I can fix, are outside of my original scope. I'll probably still fix this, as due to my previous build, I can replace all of the drivetrain since the original drivetrain was rusted to ****. I'm just hoping I don't discover worse cancer. As it is, I'll be stripping everything on the undercarriage and redoing it for sure now based on what I've found so far in the engine bay.

 

So, in the quest for a pretty engine bay, I decided to attempt to use something in place of welding.





This is POR15 Patch instead of a weld. I decided to try to experiment with it by approaching it similarly to how I would weld it, and I cut out a patch of sheet mild steel to handle the majority of the bulk. Now, here's the surprising result: It's able to hold without budging most of my bodyweight. I can put more weight on it than I am comfortable, and it seems to have no affect. This is promising, and beats the pants off welding. Note that this is only patch applied around the edges and I ground off the patch on both sides.

This is the most successful of the attempts. I have some much more poor attempts, but those were my fault, not the product. Here's an example of one:



Now, this looks visually bad, but it's actually fine. This is the result of me sanding it with a 40 grit sponge. Now, what I had wish I had done is followed the procedure I did with the above plate. The key is to apply tape to the forward facing part, in this case, I should have applied tape to where you can see. Put the steel plate there. Then go nuts with patch from behind. Don't go in from the front. However, I am not overly worried. You can see a place where a bubble developed and was found in sanding, even, but this will easily be covered and levelled out by the next coat (Effectively primer coat). In addition, both of these holes are surprisingly strong. Like the previous one, I put most of my weight on it, and nothing was impacted. It'll be interesting to see how these work long term, as it will substantially impact how I do projects if this is not only reasonably strong, but holds well long term. I'm very happy to do this over welding, it is substantially faster and cheaper. I just hope it will last as long as a good weld and grind.

 

So, instead of indefinitely putting off updates for when the car is the in the perfect state, I decided to hold myself accountable and actually post updates.

The engine bay has now been repainted. I've repaired almost all of the rust across the car (there's a few spots still left, of course), and I've begun the long process of stripping everything from the interior and then adding sound damping, then rewiring everything. Currently working on pulling doors apart for both power windows and power locks, and found rust in the driver's side that I am in the process of repairing

 

It's been awhile! Things have happened...


Engine is now in! The major things are now installed, including fully manual brakes (6:1 FIA cert'd dual reservoir stuff), DBW, stupidly overspecced alt (150 or 160 amps), and some gore where the engine hit while the paint was still too fresh. I'll fix that when things are closer to being done.



Suck my dick sanding. This NB ladder brace was so rusty it took me around 6 hours of sanding. Gotta paint the other side then undercoat for the bottom, but I wish there were aftermarket equivalents widely available. Well worth the money over the time spent sanding.

 

The car is looking great! Sanding and de-rusting things like the subframe, bracing, and brackets/misc has actually been the most annoying thing on my rusty FD. Though the end result is worth it. Anything that can fit in a bucket of evaporust should, it works miracles - though the stuff isnt cheap.

It looks like you are using all the right parts in that engine bay pic, so good on you! What IM/TB setup is that? Looks snazzy.

 

Which throttle body is that? If it’s a Bosch, I highly recommend isolating it from vibration. You may be OK with the BP and mild engine mounts, but they really do not like vibration. Winning Formula makes an incredibly nice kit to do this.

 

Ugh. I am so sick of sanding, but the car's rust has been completely sorted out. I don't really trust things like evaporust, Muriatic acid was sold to me as gold at one point, but if anything went slightly wrong, it could then keep eating away at the metal. I could probably stand to learn some new things, but sanding works and tends to be cheaper anyways in trade for some time, but it also allows me to get it exactly right without any compromises or tradeoffs.

The IM/TB is a Skunk2 with one spacer and a Bosch Motorsports DBW TB.

Fortunately, it's not the same TB that Kpower uses. However, I intend to use rubber mounts for the engine, it's not worth the NVH. We'll see what happens.

 

Correct me if I'm wrong, but evaporust is not an acid based solution and should be safe for just about anything. Though I do rinse the parts after. It takes a lot longer than muriatic acid to work though, but it does work well!

 

May be the case. After the level of effort I've gone to on this car, I am not about to use a solution I don't trust. Had bad results with muriatic acid previously. I know sanding and wire brushing takes awhile, but I can count on the results.

 

Well, finally finished wire brushing and everything
Whole bottom is now treated with a top tier undercoating. All bracing, exhaust, etc. is now in with upgraded 12.9 hardware


**** you rust. Had to cut into the bulkhead to get at this nut, it's fucked from rust. I'll be ordering new bolts and considering options.

 

Somehow I missed this. Progress looks good! Didn't you used to have a different user name?

 

Had a couple build threads at this point. This car is an unholy hybrid of the NB you/AR worked on and the NA I bought over here! Once all is done, everything will be NB but the chassis itself.

 

Evaporust uses a chemical voodoo process called selective chelation. It essentially rips the iron out of iron oxides (like rust and bluing) but is too weak to attack the iron in steel.

It's amazing stuff, so long as you can immerse the parts in it. The other downside is that it works so well that you'll get flash rust if you don't protect the parts after you rinse/dry them.

I used to use it all the time on fasteners that I removed from my cars and wanted to reuse. I switched to buying metric JIS bolts/nuts in bulk and replacing anything that's even remotely crusty.

 

Hey, glad to hear it worked great for you. But much like you mentioned, I just buy new bolts in bulk (Stainless steel for non-critical components, grade 12.9 for anything that takes stress), and I know wirebrush+sanding+paint will last for the life of the component for anything I do it to.

As for Evaporust, it's not that I don't think it will work or anything else. Just that I know what I am doing works, and works well. It may take longer, but this is a build where I am letting my perfectionist streak go wild with and I am going for stuff that in my experience has worked. It's not a build I particularly want to experiment much with (Minus the Por15 Patch ofc, but I was pretty confident that would work well going into it).