13BTT-REW FD3S Rebuild -- Disassembly

• Overview
• The Core
• Disassembly
• Cleaning
• Evaluation
• Assembly
• Mounting
• Intake/Turbo
• Cooling
• Accessories

With the engine sitting on a low table, I started by unbolting practically everything external. It is VERY helpful if you have the Mazda Factory Service Manual (see Google - I'm not sure if I'm allowed to link to that), but not absolutely necessary (yet). Most bolts are attached to logical component groups. It's a good idea to keep bolts together with their respective parts. There are plenty of areas where bolts have the same size but slightly different lengths, and it can be frustrating later to find the right one.

This yielded two boxes of parts, most of which will be either discarded (cut ends of old hoses) or put up on eBay (the twin turbo assembly). I then used two of the largest end housing holes and bolts to attach the engine plate from a Habor Freight engine mount to the side of the engine. Using a shop crane, I maneuvered the engine to the engine stand. You have to be VERY careful at this point. The engine stand isn't all that huge, and the engine is VERY top-heavy. If you don't lock it down at this point it can easily rotate so hard and fast that it could take your hand off if you got it caught between the engine and the stand. I used the shop crane for support whenever I needed to rotate or move the engine around.

Words of wisdom: Put something BIG and absorbent under your engine stand during this process, and stand ready with paper towels too. I wasn't sure what to expect, so I had cleaning supplies ready, but not nearly enough. As you disassemble the engine, coolant and oil just pour out of all sorts of unexpected places. I would have been much better off with one of those plastic-and-cloth disposable painter's tarps instead of my small oil tray.

Removing the flywheel nut is supposed to be an experience, and it was... but not the way I expected. I had to make a two hour road trip to find a tool supplier that had a 2-1/8 socket, a real beast. (I could have ordered it online, but that would have set me back a week.) Actually removing the flywheel only took a few seconds with an impact wrench. Not really that exciting. Removing the flywheel took over an hour, though. My puller was junk and careful prying barely pulled the thing a millimeter. I finally ended up buying a new puller, AND lifting the engine just slightly with the shop crane attached to a rope wrapped around the flywheel to finally get the stupid thing off.

I then proceeded to disassemble the engine core itself, following Mazda's instructions from the factory manual to the letter. This is a very exciting step. There are lots of people who "work on their car" who never see much more than the fan belts - the actual guts are beyond the reach of most people without special tools and shops.

I kept all of the tension bolts and numbered them, so they can go back into the same holes (if they're serviceable). Disassembly is very exciting. I also carefully laid out every part in sequence on my bench and made some initial evaluations. So far, I'm pleased with this core. I was worried about this core because when I first started the disassembly I noted that the rear housing was full of oil. Dirty oil, not clean oil used to preserve the engine for shipping. Also, the plugs were rusted, and the intake was full of rust and old fuel deposits. But the core is much better. There's no sign of rust (the rusted plugs must have been scrap used to close the holes for shipping), there are no scratches, dings, or signs of wear on the housings or rotor tips, and all seals are intact.