Rotary Resurrection - Tech Section


Though the 87-88 and 89-91 models differ slightly, their overall layout is almost identical and so this writeup can cover them both.

(some of the pictures may not match the model exactly, and are used for illustration only)

Remove hood from car. Remove battery. Jack up front end on jackstands securely, drain coolant from both the radiator and block (drain is located on drivers side intermediate iron) and oil.

Remove air intake snorkel, air filter box with air flow mete, leaving inlet duct on turbo.
Unplug radiator level sensor (top, center), remove overflow hose (can be on radiator or engine fill neck), remove upper radiator hose, unbolt engine fan (use a box end 10mm wrench and a long flat screwdriver to keep it from spinning), remove lower radiator hose and heater core extension hose, unbolt the radiator with shroud installed and remove. 87-8 models will have 2 wires at the bottom of the radiator which must be unplugged.
  Remove TMIC for access.
Disconnect throttle cable from engine by sliding it upwards out of the fork bracket. You may need to loosen the 2 12mm locknuts. Lay it aside behind the brake master cylinder. Remove cruise control (if equipped) cable from throttle body and unbolt it from fender well. Lay it aside. Pull the charcoal canister out of it’s bracket and lay it out of the way. IF equipped with a subzero starting bottle, remove and discard (per mazda TSB) as it serves no purpose. Just cut or remove the hose at the engine connection, it will not form a leak. Unplug wiper motor.

Inside the passenger kick panel, pull back the carpet and remove the plate to access the ecu. Unplug the 2 left most plugs on the ecu, which lead to the engine harness. Follow this harness up into the kick panel and unplug the remaining connections. S4 models have 2 large orange plugs and 2 small white plug; s5 models only have 2 large yellow connectors to unplug. Pull harness out of firewall carefully and lay across engine.
Unhook the brake master cylinder vacuum supply from the upper intake manifold (firewall, behind throttle body)
Remove the P/S and A/C belts (this car had a/c removed already)
  Remove upper oil cooler line. IN the pic above you can see the wrenches I use for removal. You must securely hold the smaller nut while loosening the larger nut. Sometimes cheater bars are required. Failure to hold the smaller nut from turning can crimp the metal fitting on the hose.
  Unbolt p/s hoses (1 or 2 on top plus one on the side, be prepared to plug the PS reservoir to prevent spillage) and wedge them aside out of the way, wires (2 plugs by engine fusebox) and lay them on top of the PS pump, and remove plug wires from engine and lay aside out of the way. Disconnect the electrical plug for the a/c.
Disconnect the 2 fuel lines on the drivers side of engine carefully and wedge them aside. Disconnect the hose at the firewall for the charcoal canister and wedge it onto the engine out of the way.
Disconnect alternator wire and plug, and on series 4 models the crank angle sensor plug.
Unplug wire to oil pressure sending unit, below oil filter. It slides off to the side. Unhook coolant hose under the oil filter. Unplug the plug(s) at the oilpan by the motor mount.
**At this point you need to decide if you will pull the engine with transmission attatched both out at the same time, or pull only the engine while leaving the transmission in the car. **
Pros of pulling the trans out with the engine are that you don’t have to get at the bellhousing or starter bolts to get the engine out, it is easier to mate the engine and trans on the floor than in the car, you can clean and inspect the trans while it is out, and you eliminate any risk of damage to clutch, input shaft, or pilot bearing/seal during removal and mating.
Cons of pulling the trans out include the need to drain trans fluid and drop more of the exhaust and driveshaft. IT also means you need a larger working room both to get the engine/trans out and to store them. Plus your hoist setup must be capable (for those of you rigging up questionable hoists) of lifting the extra weight and size.
Pros of leaving the trans in the car are that you don’t have to fool with anything rear of the clutch/starter, you don’t have to store the trans and associated parts while out, and you don’t have to drain the trans fluid or pull the shifter. IT works better in a confined space since you can pull forward a few inches and then lift straight up, rather than having to continue forward and up to clear the trans of the firewall.
Cons are that it is probably more difficult for the novice to reach the bellhousing bolts, support both the trans and motor at the proper angles as you pull the engine, and do so without clutch or input shaft damage. It is also probably more difficult to realign everything upon install. To do so requires good lighting, a good hoist setup (a load leveler is preferable), ability to observe and understand the angles and distances involved, and a few prybars to adjust those angles.
For those who have never done a remove and reinstall before, I would recommend pulling the trans out. For those who have a few under their belt and are more confident and experienced, you might try leaving it in. Much of it is personal preference, and both methods probably take about the same amount of time.

I will cover both aspects below.

**Assuming you are leaving the trans in…
Remove the 14mm nut and washers under the passenger motor mount, under the frame.
Remove the 14mm nut and washers from the top of the drivers motor mount.
Unbolt exhaust from downpipe. It is usually easiest to leave the downpipe on the engine, and unbolt the midpipe from it. Remove hose from split air pipe.
Remove starter from transmission. It can hang from the wires, they do not have to be disconnected. The upper bolt has a nut on one end that has to be held with a wrench.
Remove the rear oil line. Use a 15/16” socket. Don’t lose the 2 copper crush washers.
Remove the bellhousing bolts. They are all 14mm. There are 2 bolts on the drivers side, 2 on the passengers side, and one nut on top.
Support the trans with a block of wood and a jack. As you raise the engine, you’ll need to raise the jack a bit to maintain support.
Pull the engine up until the motor mount studs clear, then jostle the engine side to side and front to back to get it to slide off the trans. Pull the clutch completely away from the engine, then proceed to lift the engine a few inches.
Now you have clearance to get the 4 12mm bolts out of the a/c compressor. Remove it and let it lay beside the frame rail, still connected, so you don’t lose any charge.

Remove the engine completely.
**Or for those wanting to remove the trans with engine…
Disconnect slave cylinder(from transmission, NOT the hose). Don’t lose or damage the small black box that is held under the head of one of the bolts. You need a u-joint and extension to get on the bolts. DO NOT press the clutch pedal while the slave is off.
Remove shifter from inside. Lift up the trim ring, remove the 3 10mm bolts and pull it up and out.
Remove the exhaust, starting at the exhaust manifold. Though it is possible to remove only half of a stock exhaust (back to the Y) the bolts are usually so rusty that it’s adviseable to drop the whole system rather than try to get it apart. Remove all the hangers except for the rear most ones, then remove 1 on each side, and again 1 on each side, at which time it will drop.
Remove the exhaust shields, and drain the transmission fluid (unless you have a method to control fluid spillage from the tailshaft). Disconnect the starter and transmission wiring, but leave the starter on the tranny. Remove the driveshaft. Unbolt the 14mm nuts on the motor mounts *inside their round holes on the frame*.
Disconnect the rear oil cooler line (15/16" fits well) prepared for oil spillage. Note that there are 2 copper crush washers here, that must be replaced or reused on reinstallation. Attatch the chain for the engine to the rear hook. Then remove the 4 14mm bolts holding on the transmission will drop about 4-6".
Remove engine slowly from the bay. Stop after about 6-9" to remove the 4 12mm bolts from the a/c compressor, and use a wire or bungee cord to tie it up out of the way, it remains in the car, and thus the a/c system is not compromised by the swap.Also put the rear oil cooler line UNDER the d.side motor mount, so it is not pulled up with the engine. Disconnect the main ground wire from the engine/'transmission/starter area. Check to be sure all other hoses are disconnected before proceeding.
Rotary Resurrection - Tech Section
Rotary Resurrection
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