Rotary Resurrection - Tech Section

Once a fresh rebuild is assembled and installed there are a couple of things to do before trying to make it run. Here is an outline, as well as breakin recommendations. These can apply to any rebuild, professional or self-built. Many of these recommendations will vary by builder, parts used in the build, and specs of the build (porting, etc.) but the basic idea remains the same.

Remove EGI fuses underhood (if working on a carbed or modified model disable fuel and spark to prevent starting).

Crank for 10 seconds at a time, once per minute, at least 3 times, to prime the oil system and build oil pressure before startup. You can usually see 20-30psi of oil pressure during cranking. Now is also a good time to inspect the oiling system for leakage, such as oil cooler lines, oil filter, pressure sending unit, turbo plumbing, etc.

Inject some oil into the lower plug holes of each chamber to help build compression for startup. Fresh rebuilds with old housings are very low compression initially. Many builders, including myself, ship engines already lubed this way.
Make preparations to idle the engine up before startup. A rebuild will usually not even consider idling normally for the first few hours, especially a used housing build with some wear on the rotorhousings (and thus lower compression). Use the hard idle set screw(on throttle body by linkages, 8mm locknut with screw inside) to adjust the throttle somewhat open at idle, a few turns are necessary. You want the rebuild to idle at around 1500rpm for the first day or more. IF you don't do this ahead of time, and you're by yourself, youll likely be stuck inside the car holding the gas instead of outside checking for leaks and such, and if you stop the engine it'll be hard to get started again.
A battery charger or external jump(another car) is sometimes helpful in starting a rebuild, as old or partially discharged batteries sometimes lack the strength to really kick over an engine and build enough compression to start. A strong charge is a must here.
Be prepared for smoke…there is assembly lube in the engine, which will be burned out in the form of smoke. Expect this to get into your exhaust and smoke can remain for up to 3 hours afterwards until it is all burned out slowly. Most of the smoke should subside within 20 minutes.

Be prepared to watch for leaks…oil lines, coolant hoses, gaskets, and other connections should be examined for leaks. Youll also want to keep an eye on the gauges…oil pressure, water temperature, voltage, etc.

Once it is running and youre satisfied everything is stable, set the idle to around 1500rpm and let it be. Since compression is constantly changing, there isn't much use in adjusting and readjusting idle and TPS settings until breakin is almost complete, as the settings will change almost daily. Right now, the more you can drive it, the better. It is very helpful for the first few days even to just let it idle in the driveway all day if circumstances prevent the car from being driven, though this is not to be taken as a way to break the engine in, merely better than doing nothing at all.
For models 88 and prior I suggest a fuel cutoff switch be installed to control the fuel pump (or injectors directly, if you know how to wire such a circuit up) to prevent flooding. 89+ models should not have need for this, as the ecu and tps have this feature built in, flooring the throttle during cranking cuts fuel and prevents/clears flooding.
Breakin should be completed as follows. Keep rpms under 4000 when possible, oil changes at 500 and 2000 miles, and no boost above atmospheric (turbo models) when possible. Violating these "rules" should not result in any failure or damage to your engine, but it should be avoided when possible to allow the seals the best chance to seat and seal well for the future. Beating on an engine before breakin could result in poor compression and an even longer breakin.

Great improvements in starting, idle quality and overall smoothness/power will begin occurring immediately, but most improvement will be reached by 1500 miles, at which time you can gradually increase rpm and boost. By the time the engine reaches 2000 miles, it is basically broken in and can be treated as you wish within reason. IF the engine was built with some great housings, this point may come much sooner. Whenever possible, take baseline compression readings when you first get your engine running, and every few hundred miles for comparison. When compression levels off, then the engine is done breaking in and has done about all it is going to do. You sometimes pick up an additional few psi several thousand miles down the road, but this is not of concern.

Rotary Resurrection - Tech Section
Rotary Resurrection
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