I'm not comfortable posting the manuals directly, but at the moment they're available for download from RX7Club. The most important document in the set is the FSM. I strongly recommend that you print it out and put it in a 3-ring binder for reference in the shop. Unlike what other automakers produce, it's not just a manual – it's a step-by-step guide to doing a rotary engine teardown and rebuild.
The manual is fairly large, so printing it double-sided is helpful. If you want, you can get away with just printing sections GI through E, and just referring to the rest of the manual on your computer when you need something (there are occasionally-helpful charts throughout the rest of the manual).
If that link ever dies, the manuals are also available here. If BOTH those links die, you'll have to buy the printed versions, which Mazdatrix and other suppliers sell. Please don't contact me for copies.
The Service Highlights document is also interesting. I only read this document once, but what I read was interesting. It describes material and design changes made in the 3rd-gen from previous versions, and it has quick-reference tech specs that are easier to find in here than in the main FSM. Optional, but worth a read-through.
The rotary engine's fittings are predominantly metric threaded and push-on/clamp style connectors. These work fine in the car, but a common change for aircraft use is to convert to AN-style fittings. When doing this, it's helpful to know a bit about the fittings you're using!
First, you need to know how to size an existing metric fitting. A digital caliper is very helpful for this. The process is simple. Measure the outer diameter of the threaded section of the fastener. Then measure the distance from the tip of one thread to the tip of the next. It can be hard to do this accurately because the differences are often 0.25mm from one size to another, so for fine threads try measuring the distance from one thread to ten threads away, then dividing by 10.
A good test to be sure you're doing this right is to measure the banjo bolt that connects the oil line from the front cover to the oil cooler. This is a 14mm x 1.5mm (often written 14-1.5mm or M14-1.5) fitting and it's one of the ones you're going to want an adapter for.
When installing accessories you'll run into a lot of metric, but also a lot of AN and NPT fittings. The most common task is to make up a hose with AN fittings, then attach it to a metric fitting on the engine, and an NPT fitting on the accessory! Needless to say you'll be using a lot of adapters, but you can save money, size, and weight if you get as close as possible to the final dimension you want with each fitting.
“Aeromotive, Inc. Technical Bulletin #901- Sep 16, 2005” is a useful document to refer to when you're sizing fittings. There's a copy of it posted on this forum post. To summarize:
| AN Fittings | NPT Fittings | |
|---|---|---|
| Shape | Straight threads | Tapered threads |
| Sealing | A wide, 37-degree flared surface is compressed against a matching surface. | Wedging effect of threads pressing against each other. |
| Seal Quality | Good, provided both flares are in good condition. Check for scratches before mating. | Poor. Always use teflon sealant1). |
| Sizing | “Dash” (-) numbers that specify sixteenth-inch increments . For example, an AN-10, or “dash 10”, is 10/16” or 5/8” OD hose. Hose ID varies with material. | Sizes are specified directly in inches, such as 5/8”. However, sizes refer to ID, and wall thicknesses are higher, so a 5/8” NPT fitting is considerably larger than an AN-10. |
You will frequently need to convert from NPT to AN because filter brackets and similar accessories are typically NPT, and all your hoses will be AN. When doing this, it's important to pay attention to the ID of the hose to avoid flow restrictions. Although it's possible to get AN-to-NPT adapters that adapt between different sizes, if you can it's ideal to match the sizes. Here's a conversion chart of common sizes:
| AN- size | NPT Size | Thin-wall Hard Line Equivalent |
|---|---|---|
| AN-4 | 1/8” NPT | 1/4” OD |
| AN-6 | 1/4” NPT | 3/8” OD |
| AN-8 | 3/8” NPT | 1/2” OD (0.440” ID) |
| AN-10 | 1/2” NPT | 5/8” OD |
| AN-12 | 5/8” NPT | 3/4” OD |
| AN-12 | 3/4” NPT | 7/8” OD |
| AN-16 | 7/8” NPT | 1” OD |
Note that the AN fittings match the hard line sizes, and are 1/8” larger than the NPT fittings. These numbers are APPROXIMATELY related to the difference between the thickness of the wall of standard black pipe, which is what NPT fittings were designed for, and the wall of hard line, which is what AN fittings were designed for. The numbers are approximate, but are as close as you can get in standard fittings.
It's generally acceptable to step up the NPT fitting size if necessary. For instance, if you have an AN-10 oil line, you could connect it to a 1/2” NPT OR LARGER accessory with no flow restrictions. But avoid going the other way, because even though adapters are available to do that, you're going to restrict your oil flow! If you're only one size off and you simply must size downward on the NPT size, try using a steel fitting; it will have a thinner wall than the aluminum equivalent.