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I'm wanting to start this thread after looking through Jerry's restoration and seeing his awesome results. I have had a crappy (but enjoyed) car for quite a while now, and have never been able to fix it up. I pulled the engine last year and rebuilt it in June. It was then I made the decision that I wouldn't put anything back into the car unless it had been restored or cleaned up in some shape or form. It's a little cold out still, so for these next few posts, I'll be outlining what went wrong with the engine so maybe we can determine a cause, as well as show you the work I was able to get done so far. Then I will need your help for planning out what needs to happen to make this car nice and not just what got me by for many years. This is a great community for this type of work so hopefully we can come up with something good. I will try to take a bunch of pictures so that we can make some good visual guides for specific tasks. Let me know what you guys think!
Gotta go to Church, hopefully I can start uploading some pictures and describing where I am at this afternoon.
S4 Turbo Frame - Body and suspension, brakes
S5 Everything else - Engine, electrical, interior
I had been working on a completely stock S5 turbo since I was about 15 (early 2000s). Long story short, when I was in college, I cheaped out on tires, they blew out on my way from work and it was totalled 7/1/2010. Stripped everything I could save off that body, and bought an S4 turbo body. Swapped everything over I could to get it back on the road. It was my daily for then next few years until Fall 2018. Engine was not in reliable shape so wife and I bought a truck. Now, thanks to an absurd boost in business for the past couple years, wife said I could go ahead and rebuild the car.
Engine pre-restoration
S4 body was one I bought off of a chevy guy (you know where this is going). Had to have someone weld on some new transmission mounts because he had cut them off to do what chevy guys do. There is still a hole in the firewall for where he was going to put the distributor. More on that later.
I guess this first section will talk about the engine and the recent rebuild I did. That might provide the best context.
Engine history: I got the engine as a stock turbo II engine with approximately 70k miles (if the odometer was to be believed). It is possible because I dug the original car out of a mudhole up to the door handles. It was also a home to wayward raccoons at the time, but I digress... Around 2011, the stock turbo went bad, so I sent it off to get rebuilt. At the same time, I decided to have the engine gone through and rebuilt because I had no idea what condition it was in, just that it ran. Stock turbo came back and the guy that rebuilt it decided to use an impact to get the nut off the compressor wheel, and ruined it completely. I decided to cut my losses and sent it off to be made into a BNR stage 2. Engine came back with a Racing Beat template street port and exhaust port, Goopy apex seals, and solid corner seals. Drove like a grandma because I couldn't afford anything else while still in college. A few years ago, around 2014 or 2015, I started noticing that the engine was getting lower on power. Boost came on fine, and was in range, but it wouldn't go any faster. The engine developed a faint whine and tick about 2016 or so. I posted a video on here a couple years ago showing the tick noise. I tried to limp the car along for as long as I could, until the rear main seal started puking oil on the clutch. Fall 2018 was the end of that and we bought the truck.
Rear stationary bearing showing wear Rear rotor very crusty on sides. (corner seals were installed correctly. I just put them back in here so I wouldn't lose them) Front stationary bearing damage Buildup of crust around exhaust ports on rotor housings. Left a small ridge that you could catch with your fingernail Rotor 1 carbon buildup Rotor 1 after cleanup
Best of luck on your restoration! It seems like a long haul at times, but in the end it's incredibly fulfilling to see where you started and now see where you are ending.
2019 Engine details pre-rebuild:
Compression before disassembly: approximately 65-70psi on all faces, both rotors. Engine idled fine, did not like warm starts
Upon disassembly, both stationary bearings were found damaged, with the front stationary bearing being worn to the copper. E-shaft was unaffected
Both rotors were covered in carbon, on all combustion faces as well as both sides between the side seals and the oil control ring
Most apex seals were tight. About 2 could move in and out, but the rest were pinched. The apex seal grooves were free of carbon, but were tight on all apex seals. Apex seals were removed by hand though, no tools required
Like the apex seals, most corner seals and all side seals were pinched as well. The pinch appeared consistently on one end of the side seals, which would have been the trailing end of the seals as the rotors sweep. With this in mind, the apex, corner, and side seals were all pinched in at approximately the same location on each face, for both rotors. The side seal pinch zone extended about 1" from the apex seal towards the center of the rotor. The side seals could not move freely, nor could the corner seals. Had to use pliers on a couple of the corner seals to remove them. All of these locations on the rotors were out of spec. All side seals and apex seals showed no appreciable wear, and were still in spec according to the FSM
I'm really looking forward to having a nice car at the end of all this. If I hadn't lost the original car in the first place, I'd be a lot further along. Next post will be about the engine rebuild, what I've restored so far, and where I'm wanting to go next with the build
Engine rebuild specifics June 2019: New atkins seal kit
-Cleaned all rotor parts
-Apex seals reused - still in spec
-Most side seals reused - snapped one on accident
-Stock rubber corner seals replacing all metal seals
-New springs on everything - thick corner seal springs used
-Oil control rings reused (no noticeable wear)
-Rotor slots for apex and side seals out of spec were widened to spec by hand using 1000 grit sandpaper against a solid tool
-Corner seal sockets were reamed out to spec. They were .002" too small
-Every seal was ensured to move freely
-New rotor and stationary bearings installed
-Thick rear main seal used
-Step wear on irons was visible, but in spec. no sharp grooves, just a slight smooth raise.
-Scrubbed carbon lip off exhaust ports
I haven't found the root cause of this engine failure. It was not sudden. It happened over time. Somehow, the rotors were all deformed on the trailing side. There weren't any noticeable impact points on the rotor housing that I saw to indicate something peening the corners of the rotors in, other than the raised carbon lip on the exhaust ports. I expect with damaged stationary bearings there would be some deviation of the e-shaft, but a point of impact would still need to occur. Unless the carbon cushioned the blows so that contact with the housing didn't mar the chrome... I have no idea. Any input from you guys would be welcome. I don't want to have to do this again.
Last edited by professionalpyroman; 02-16-20 at 11:04 PM.
Reason: add material
Here is the pic of the bare engine bay, and some of the restored parts
Nasty engine bay Trailing coil before restoration Fan, AC/PS bracket painted Water pump, AC fan painted PS lines pre-resto Pulleys post paint. There were still the factory alignment marks stamped in them. I painted those marks with yellow so they are more visible. Trailing coil post resto Cleaned, assembled, painted short block PS lines post-resto Leading coil post resto UIM, LIM painted Hoses and tanks post resto
That hole in the firewall is ghastly, but not insurmountable. I'm sure it led to a pretty good price on having to get someone else's unfinished project.
Knowing what I know now, I would have paid a lot less, but I was quite a bit younger, dumber, and a lot poorer. I had everything else out of my former S5. All I needed at the time was a shell. I'm wanting to get this build as close to S5 as I can get.
How would you go about cleaning up that engine bay? I gotta power wash it first, but I will need to take care of the firewall, and the rust that was underneath the brake master. It's just got straight brakes. I have thought about seeing if someone has an ABS unit and lines I could run. I still have the computer for it, but I would also have to get hubs and wheel sensors. I realize a lot of guys are going away from it, but being the engineer, I like my features.
I am also planning on completely rebuilding the power distribution harness. It was crusty, and a new set would do some good. I would also like to rebuild my engine harness because the connectors and wires aren't in good shape either. The engine bay, engine, and harnesses are my biggest concern right now. Wife wants to find a new house, and this thing will be a lot easier to move in one piece rather than the piles it currently sits in.
Haven't updated in a while. Not much progress. I have been peeling the nasty slimy tape off of the wiring harnesses and been washing them thoroughly. They mostly seem to be in good shape with a couple exceptions. After stripping the ECU and power harnesses, I have noticed that the well protected parts of the harness (that were soaked in oil and grease) were still fairly pliable, while exposed areas were far more brittle. I plan on soaking the brittle portions in some armorall plastic trim repair to see if it softens up the coatings any. In addition, I have some broken wires to repair, ends and segments to replace. Both the battery positive to fuse, and ground cables were in poor shape, so I plan on remaking those and replacing them. When I retape the driver's side harness that has the coils and AC stuff on it, I plan on integrating wiring and plugs for my HKS twin power, so it looks nice and tucked in. Wrapping will be an expense for next month, recommendations are appreciated. This month's purchase was this 2 1/2gal ultrasonic cleaner for $140. I tried it out this evening and I think I'm going to get a lot of use out of it for this restoration. Gonna try it out on wiring harness ends tomorrow and see how it gets the crud off of them. Pictures of harnesses and ultrasonic cleaner. I am also looking into modding the stock ECU, as detailed in SonicRat's post, and have identified the rom chip in the N370 ecu. I am not going to pull it right now because I don't have a suitable desoldering tool. This isn't a component I am willing to risk my 200lb gorilla hands messing up. Education can't always compete with developed skill and resources. The next assembly I plan on working on is my throttle body. I am going to use that ultrasonic cleaner to clean all the small throttle parts. The throttle parts look soiled from 30 years of grime, but also the coatings have been scratched or rusted and have otherwise deteriorated. What do you guys think about nickel-plating the throttle parts? I think it would look nice and could keep them in a good clean condition for a few years to come. From the videos I have seen, this can be accomplished with a 5v source and a nickel, vinegar, and NaCl salt brine. I'm wanting to coat the throttle parts, but not add a whole lot of thickness to the parts like paint would.
Once the throttle parts look nice, I'll do an assembly write up specifically for the throttle body. Would you guys prefer a video, or highlighted photos as I have been doing in this post? https://www.rx7club.com/2nd-generati...i-fix-1142452/
After the throttle body and wiring harnesses are done, I plan on doing another write up on how the stock (mostly) vacuum system is hooked up and functions. Any interest in this?
What do you guys think about nickel-plating the throttle parts? I think it would look nice and could keep them in a good clean condition for a few years to come. From the videos I have seen, this can be accomplished with a 5v source and a nickel, vinegar, and NaCl salt brine. I'm wanting to coat the throttle parts, but not add a whole lot of thickness to the parts like paint would.
I Zinc plated all the hardware on the rear suspension of my car.
It was very, very time consuming. Take all the hardware, clean each piece individually, chemically strip the rust and old coating (CLR works pretty well), degrease it again, and again, then rinse and dry quickly so it doesn't flash rust.
Then start with a dip in an electrocleaning bath (rust starts instantly, so this is the best way to remove it at a microscopic level before plating) before moving straight to the plating bath. Move it around, swirl the fluid, flip the part over and repeat. x30 for all of the hardware.
I was able to achieve decent results, but it took ages and some parts still came out looking a bit "weird". Nothing has rusted so far, but I think the coating didn't always deposit super evenly since there is a limit to how much fine tuning you can do at home with voltage and current. I think professional places also circulate the solution, whereas I was circulating the part in the solution, so maybe I didn't do as good a job of that. If you're concerned about how the parts look, that is something to consider.
Overall, it was pretty cheap, but I'd take it to a professional place if I did it again. It's a trade-off. I saved money, but spent a serious amount of time on it.
Interested to see how the harness turns out. What exactly are you trying to soften with the Armor-All?
I've had a lot of luck with using electrolysis on steel and especially cast iron parts for restoring other equipment. Strips rust and coatings fairly well. I had noticed that the more evenly I placed the electrodes (scrap steel), the better my removal results were. Also, I used a car battery charger on 12v6a to power those efforts. Obviously won't carry over directly though. Thanks for the input, I'll have to come up with a good plan.
The armor all will be used to try to soften the hardened plastic on the exposed wiring harness portions, since the coatings have become brittle with age. I had good results using it on plastic parts and hoses listed above by marinating the parts for a couple hours. Hopefully it will bring similar results on these wiring harnesses.
I got the 10L capacity cleaner from this website. https://www.kaiezen.com/collections/storage-cleaning. They had a bunch of them on sale, and that one was at a reasonable price point. Looks like word got out though. Its a globalized chinese product, about like anything else these days. There are a bunch just like it with different sizes/brand stickers, but the same manufacture.
Last night I went out to the garage and tried it out after everyone was asleep. First observation, that thing makes an obnoxious sound when it runs. Good thing the garage isn't attached. Not overly loud, just annoying. The second is that it takes forever and a day for the tank heater to heat up. Low wattage heater. It gets plenty warm, and you'll need it to get anything greasy cleaned off. I ran it up to about 140F (it's labeled in metric, so 60C on the machine) and it took about an hour to get there. Then I just started trying to clean stuff. Hot water with dawn dish soap was the cleaning medium.
I started with the greasy wiring harness ends. I hung them in the bath, but kept the good ends that didn't require cleaning outside. It wasn't as effective on these as I thought it would be. The hot soapy water was probably the most effective against the grease. The actual metal terminals were cleaned, but the plastic plug ends didn't clean up as well. I was able to blow a lot of the loose stuff off with compressed air after though. Before cleaning After cleaning After cleaning
After After After After After After After After After
So what I noticed as far as results. These parts were washed concurrently. If you try to use the ultrasonic to clean rubber parts, you're better off with a bucket of hot soapy water and a scotchbrite pad. Rubber parts don't clean up with this (nor would it make sense to). Hard plastic parts like the stock BOV, harness ends clean up better than rubber, but the hot water is still doing most of the work.
As far as metal parts, the more surface area on a part, the better. The stock turbo outlet pipe cleaned up spotless, and it is cast aluminum with a higher degree of surface roughness. The cleaner didn't leave any soilant on it at all. The block off plate had all the loose particulate removed, but the corroded areas still had rust. The fuel rail was in a similar shape. It was clean, but still oxidized. Bolt threads still had debris in them, but were easily cleaned off with an air compressor. The blitz BOV was sticking when I used it last, even though the bore looked like it was fairly clean. After washing and reassembling, the piston slides smoothly in the bore.
Overall I think I have learned a few things with this. Plastic parts really aren't worth your time with this ultrasonic machine, unless you are just using it for hot water while you scrub. Cast parts are perfect for it though. It gets in all the little corners and everything. At most on a cast part, you will want to rinse/blow remaining debris off. On smooth or sheet metal parts, it seems to do ok too. However, you want to make sure that the plane of your flat part is oriented normal to the transducer on the bottom of the machine for it to clean the best. Gonna keep using it, but now I know what to expect from it. It's not a replacement for elbow grease in most cases, but it can help.
If you look in the photos, a lot of my parts have that oxidized look like the fuel rail. All my throttle parts look like that, with some rust mixed in here and there. I had mentioned wanting to try nickel plating earlier. Are there any other coating options you guys would recommend? I have painted a lot of parts so far with engine enamel to mixed results. Some parts just flake off after drying, even with primer. I like the plating idea because it doesn't add an appreciable thickness to the parts like paint would. What about cold bluing? Other options?
So I got to spend the day out in the garage and I learned some more. I changed the water in the cleaner, and used it pretty much all afternoon. I tossed some more car parts in as well as some tools I'm restoring. While that was running, I went and got a gallon of evapo-rust. I pulled the parts out of the cleaner and soaked them in the evapo-rust for a few hours. There were a couple of batches going. Every hour or so, I swapped them from the evapo-rust and the cleaner. Alternating between the chemical and physical attacks blasted the heck out of surface rust. It also removed the yellow coating on some parts. However, they are much cleaner than I had been able to get them with soap and water, and wire brushing. I plan on doing more tomorrow and will take some pictures. It was pretty impressive cleaning.
Its been a while since I last posted on here. Made some progress on cleaning and restoration. I am also including other stuff.
Here's what I've gotten done since the last post
-Nickel plating: Small parts like my throttle body were all rusty, and in poor shape. I restored these parts by alternating between evaporust soak and soapy water in the ultrasonic cleaner until clean and rust nodules are gone. From there, parts went into an acetone rinse, then into the tub of nickel plating solution I made. Solution consisted of distilled vinegar, a couple tablespoons of salt, and then using the power supply, saturate the mixture with nickel by running it with nickel electrodes on each polarity until the mixture was saturated (precipitating nickel particles). Power supply was made from an old ATX PC power supply that was giving me issues. I made it selectable between 3.3v, 5v, 12v. General instructions can be found on youtube. Need to source a better rotary switch because these ones keep burning out. Brine was made at 5v, low and slow. Plating was done at 5v, or in the case of larger parts, 12v. The problem with 12v is that it puts out a LOT of heat and the wires on the sides of my bucket were starting to melt down through the bucket. Its what burnt out the switch. Average current at 5v varies between 1.5 and 8 amps. Average current at 12v is about 12-15amps. 5v plating takes a few minutes and often requires repositioning the part within the electric field to get a good plate. 12v doesn't care. It plates on hot, fast, and thick. I've gotten better results at 12v, but I need to figure out how to keep from burning up switches. Maybe a big ol' mosfet with a heat sink will take care of it. This nickel plating is for rust mitigation and prevention, not necessarily cosmetics. These are typically parts I'd rather not paint. I'd have used this a lot more if I had this setup to start with. If you have questions on this, let me know. It worked out really well for what I am trying to accomplish. Photos now
Making brine with both electrodes nickel Plating dashpot. Note that nickel ribbon is wrapped around periphery so that electric field is evenly distributed Side photo of dashpot post plating. It got in all the pitting left from the rust after it was removed. You can read the letters now!
-Rebuilt power harness: As previously posted, you know I am going through, cleaning up, and restoring the wiring harnesses. This is the restoration of the power wiring harness. Photos above show how dilapidated it had become. I didn't have to do as much to this as I thought. Upon inspection and cleaning of the harness, there is only a couple connectors I need to order, and the rest is wrapping. Mazda put flex tubing over a few parts of the harness, and some of that had been chewed up or fell apart over the years. I replaced the bad portions, and added more flextube to the harness to provide some resiliency. When Mazda put the flex tubing on, it was only typically at the major wire runs, with your sensor and smaller individual wires being left to the elements. I put flex tube over those individual wires as well to protect them all the way out to the terminations, and provide some strain relief. Wrapping the harness was done using Tesa impregnated-cloth tape. I got it off Amazon in a 5 pack. It wraps really nice and has very little stretch so you can make some neat and clean wraps without it scrunching up on you. The only aggravation I had with it is that it frayed along the side like duct tape when you unroll it. Other than that it looks good, and is much more flexible in my opinion than the electrical tape would be. Not gooey either. Wires were wrapped smallest to largest. Like a tree, the main trunk was identified and wrapped last. Individual branches were wrapped by first making a tucked wrap at the terminations, then wrapping back to the trunk. Once the wrap met where wire runs join, a couple wraps around the joint were made to strain-relieve the branch. Once all the branches were wrapped. the main trunk was wrapped from the starter terminations back to the battery. By having the wire run joints wrapped in such a manner, the main wrap went around all the "loose" ends and captured them in the main run, preventing unraveling. Wrapping was done all the way to the battery terminals.
I also replaced the battery terminals with these knuconceptz terminals.
. The old lead terminals that were on there had seen their last. If the car hit a pothole, they would fall off. I needed to replace them without shortening the main power and ground wires as I wasn't sure if I would have enough length left. I soaked some shop rags in water and wrapped them around the wires just up to the terminals and then melted off the old terminals with a map torch until I had the bare ends. The wet rags soaked up heat from the torch and prevented damage to the wire insulation. With the ends exposed, I was able to install the knuconceptz terminals on the existing wires at the same lengths. I got these terminals instead of new lead ones because these looked like a clever way to be able to add on if I wanted to. Once I complete my install, I'll probably make a nice harness for my HKS Twin Power and make it mate up to these with better connections. Let me know what you think of this harness. I'm pretty happy with how it turned out.
-Rebuilt throttle body: I rebuilt my throttle body after thoroughly cleaning it in the ultrasonic cleaner, and plating all the little parts. It is not adjusted or set yet, just reassembled. I am fairly convinced that this process fixed some of my idling evils I was having. Before rebuild, the primary throttle plate would sometimes not return all the way to the stop screw (it's not an idle adjust, I need to make a video), and would hang the idle high at stop. Sometimes it would close after, sometimes it wouldn't. Now it snaps back every time, with some resistance from the now super clean and pretty dashpots. I have full faith that a lot of that was the ultrasonic cleaner getting crud out of all the springs and bushings. That 2.5gal cleaner I have was just big enough to accommodate the stripped throttle body. I need to get everything adjusted and set for initial tuning. Photos of my results
-Restored PS pump: This thing was disgusting and looked like an eyesore. Three days of cleaning, a new bearing, and new paint. Before Before After After
-Cleaned turbo: Took off the compressor housing, feed and drain tubes, and wastegate actuator and cleaned them. I also took off the turbo blanket to find it had disintegrated. One whole side was rotted away and all the fiberglass, or whatever insulation it is, fell out. I only got about 2.5 years of daily highway driving out of it. Gonna ask the manufacturer if I misused it, or if that is the expected lifespan. I got to thinking and examining the wastegate system. The S5 turbo has a boost control circuit that I had kept hooked up. However, with this setup, the wastegate actuator (BNR stage 2) is listed at about 12psi crack pressure. This is much higher than I should be running with a stock ecu, and likely the reason I had to rebuild in the first place. If I were able to swap this out with a stock pressure rated one, the computer could limit boost as normal until I have the means to run a better fuel control setup. Do you guys know of an actuator that would fit the BNR setup and operate at this lower pressure? From what I can tell about the stock boost control is that it bleeds off air until the MAP sensor reads the topped out boost level for the stock ECU. The boost control solenoid then closes and allows the actuator to pressurize and open the wastegate. If I had a 12psi crack pressure previously, then the boost control circuit would have been rendered completely useless. I do plan on doing tests to see how much you can accomplish with the stock boost control circuit and adjusting duty cycle, but I am definitely wanting this engine protection feature back. I have a feeling if I knew better a few years ago, it would have saved me some headache.
-Sous Vide: Lastly, we've been stuck at home like everybody else for a while now. I haven't had the expendable income to work on this car as much as I would like, so I have to make due. I had been wanting to get a sous vide machine to try on meats, because all our steaks in the freezer were 1" t-bones. Just cooking those in a cast iron pan leaves them black on the outside, and still raw in the middle. Wanted a better solution to this, then it dawned on me. My ultrasonic cleaner is about the right size and temperature range, it just might work. Gentlemen, I present you ultrasonic sous vide! 4 hours at 130 degrees (50 metric), then remove, brown in cast iron pan, rest and serve! Medium rare and fork tender, all fat rendered.
Water pre-heated Keeping bags in postion 4 hours later perfect
My next project is to finish cleaning up all the little parts, odds and ends, clean the engine bay, re-wrap and fix the other wiring harnesses (I'll need your input on those), and get ready for reassembly. Getting closer. I am wanting to do a series of videos for new guys, since it looks like the next generation are starting to get ahold of these cars. These videos would include a tutorial of the stock vacuum systems and how they work, throttle body systems and how they work, etc. It may seem a bit patronizing, but think about it this way, I have had both a mix of analog and digital electronics in my lifetime, but know a lot more about analog systems. My kids, as well as the high school and now young college kids have only had digital stuff, electrically controlled systems, etc. This stuff is pretty much antique, almost lost tech. I think it would do our community good to put out something like that, maybe have a channel on youtube, or get an existing one to assist with putting this content out there. It would be good to have a here's what this is, here is what it does, and here is why you need it. Would you guys be interested in doing something like that?
Today I worked on adding a vacuum port to the EGR block off plate. I had done some searching and it looks like under the stock configuration that the MAP sensor connected to the vacuum port on the EGR. From what I can tell, the port coming off the EGR was more of a thru-hole and convenient place to put the vacuum nipple. I had previously been using the vacuum port on the back side of R2 primary passage on the UIM for both MAP and BOV. By adding this, I could separate the two and still have both operate from primary intake sources. I don't know if there is a difference in operation between hooking the MAP up to the R1 or R2 primary, as any slight vacuum pulses would be 180 degrees apart from each other. I don't know what sort of filtering the sensor or ECU does to mitigate noise like that. There is the small vacuum pill that goes in that line to reduce the noise from the pulses, but to see any actual effects would take a functioning oscilloscope. Here is a picture of the vacuum port I added. I turned the tube down on the lathe and pressed it in. I then peened the back so that it would stay in permanently, and nickel plated it for rust prevention. I think it looks ok. Might be an overkill solution, but it's closer to the correct configuration that before.
1937 Atlas/Craftsman 101 Manifold port to install Matched to gasket position Front side
Got a lot done lately. Hope to start it this weekend. I have been recording some vacuum system videos, but they're gonna be pretty rudimentary and recorded on a cell phone. I will update after I get it running.
02-16-20, 09:29 AM
