Rotary Resurrection - Tech Section
93-95 Engine Teardown From Longblock To Shortblock
This shows you how to take a stock longblock (the engine as it is removed from the car) and strip it to a bare shortblock, which is how most engine rebuilders (including myself) generally request the engine be sent in for work. I do give customers the option to ship the engine to me in longblock form and I will perform this teardown and reinstallation for them.
This writeup starts with the engine on the stand, with the transmission and clutch having been removed, as well as the a/c, p/s and bracket removed. IF you are shipping a longblock engine to me then this is how it should be sent.
Remove the pressure chamber behind the alternator. BE careful removing vacuum hoses from all plastic nipples during this teardown. Some choose to use a razor knife and peel the hose away, I personally use needlenose pliers and twist the hose off the nipple. I would assume that you would replace all the hoses during this teardown/assembly so I would not personally bother mark them during removal, but if you plan to reuse them, you may wish to do so.
Loosen alternator tensioner and if necessary airpump adjustment, and remove the serpentine belt. Unplug the airpump electrical connector. Unplug the white single wire coolant level sensor on the thermostat housing, and disconnect the small coolant line on the back of the waterpump housing leading to the vacuum rack.
ON the back corner of the engine, remove the harness clip from the bracket, and unbolt the harness ground from the upper intake manifold.
Remove the 4 nuts and 1 bolt holding the upper intake to the lower intake. Remove the 2 10mm bolts holding the 2 solenoids onto the front of the UIM.
Remove the vacuum hoses and loosen the 12mm bolt holding the UIM to the bracket by the throttlebody.
Disconnect the coolant hose on the bottom of the throttlebody and the one on top (backside of engine). Unplug the TPS on the back of the throttlebody.
Unplug the vacuum hose to the double throttle valve on top/back of the intake, the 2 valve plugs on the back/underneath the UIM, the vacuum hoses, and the IAS plug farther underneath.
Remove the UIM. Sometimes if the gasket is sealed really well, you may have to hit it by the throttlebody with the handle of a hammer or a rubber mallet to break the seal. Lift it straight up being sure nothing is still connected.
Disconnect the vacuum hose the the emissions canister by the oil filler neck. Remove the vacuum hose to the oil filler neck. Remove the oil filler neck and the dipstick.

Bolt the bracket in place on the rear rotorhousing, with the harness routed underneath, and the ground wire bolted in place.

To run nonsequential on a stock computer, you have to run resistors in place of some of the solenoids to avoid computer codes and a CEL. With a PFC this is not necessary. You need 330 ohm ½ watt resistors from radio shack, as well as male terminals.


Remove the vacuum tank from the front corner of the engine.

Remove the 2 solenoids and the lines from behind the air pump.

Unplug the oil metering pump and crank angle sensor plugs.
Disconnect 2 vacuum hoses and the green coolant temperature sensor plug on the back of the waterpump housing.
Unplug the top solenoid, remove the 2 vacuum hoses from it, disconnect the 4 vacuum hoses to the LIM nipples, and the fuel rail thermosensor.
Disconnect the 2 vacuum hoses to the ACV and unplug the rear secondary fuel injector plug.

ON the upper fuel rail, remove the vacuum hose to the fuel pressure regulator, and the fuel hose from it.

Disconnect the lower fuel hose.
Disconnect the 2 vacuum hoses to the 2 oil metering injectors. They’re mounted to the top of the rotorhousings facing the LIM, far down under the rat’s nest, follow the vacuum hoses up to where they connect on the rail.
Remove the 3 12mm bolts holding down the vacuum rail.
Pull the vacuum rail back about 2” for clearance.
Unplug the 3 plugs under the ACV.
Unplug front secondary fuel injector.
Disconnect the vacuum hose that goes under the vacuum rail to a nipple on the lower intake manifold. It’s buried far back in the middle of the mess. Pull it off the LIM and out of the way.
Work the rear throttlebody coolant hose under the vacuum rail. Be careful with the hose if you intend to reuse it…they get very soft at the end that is over the nipple. Pull the rail back another inch or 2 for more clearance. You can now see the nipple and hose mentioned above more clearly
Disconnect the larger vacuum hose on the front of the vacuum rail.
Now you can more easily get to the second coolant temperature sensor (under the green one) on the back of the water pump housing. Disconnect it.

You should now be able to disconnect the lower fuel injector plugs.
Disconnect the knock sensor plug.
Unplug the coolant temp sensor from under the oil filter.


You should now be able to remove the entire vacuum rail with wiring harness. Pull it up slowly to be sure nothing is hung up.

Remove the rubber hose for the primary turbo intake, and the air pump.
Disconect the OMP oil lines at the OMP and lay them aside, permitting removal of the waterpump housing later. Lay OMP wires out of the way as well.
Disconnect the rubber coolant lines feeding the turbos, both the upper and lower rubber lines near the waterpump housing.
Remove the water pump pulley.
Remove the 12mm nuts (not the 10mm bolts) holding the waterpump housing to the engine. Also remove the 12mm bolt holding the alternator bracket to the waterpump/housing.
Remove the waterpump housing with waterpump and alternator from the engine. You may need to use a rubber mallet or the end of a hammer to jar the housing loose from the block. Don’t forget to remove and save the waterpump housing spacer that goes behind the housing on the 2 left most studs.

Remove the rear turbo intake tube.
Disconnect the 3 vacuum hoses from the LIM to the charge pipe.

Remove the Y pipe vacuum line…

Remove the Y pipe. IT twists in the center if you have a hard time removing the ends.

Disconnect the turbo oil feed line. You need 2 17mm wrenches for this, hold the left line while loosening the right one. Failure to do so can damage one or both lines.
Disconnect the 2 vacuum hoses (be careful, the nipples break easily) and the 90* intake elbow from the front turbo. Then disconnect the 4 lower turbo vacuum lines from the metal spider, and remove the spider…
Disconnect front and rear turbo oil drain pipes from the engine…the rear one at the block, the front one at the extension tube coming off the front cover.
Remove the 2 lower turbo heat shields…
Remove the 5 14mm nots (the studs come with them often, this cannot be avoided), 1 12mm nut, and finally the 2 14mm bolts. Be prepared for the (heavy) turbos to fall at this point, because the studs usually come out of the manifold leaving it free to move.
Remove the 2 bolts and the C clip underneath the manifold that hold the actuator on…remove the actuator, then the heat shield on the manifold.

Remove manifold and gaskets. It’s a good idea to lubricate the studs before removing the nuts, you don’t want the studs coming out of the block if possible, though it is unavoidable at times. The problem is that sometimes the stud damages the rotorhousing aluminum on the way out, which is not a good thing for the rebuild.

Unbolt the lower fuel rail with injectors, and be sure to get the spacer underneath.

You can now remove the lower intake manifold. Again, sometimes a tap is necessary to break the old gasket seal.
Using a 19mm wrench, remove the oil metering injectors from the block. The lines will come loose as well, be careful not to break them, they are brittle. They are perfectly reuseable so long as you do not break them in handling or removal/installation. Also here is another shot of that waterpump spacer, a reminder to remove it now if you haven’t already.
Remove oil metering pump from front cover (3 bolts) and the turbo oil drain extension tube.

Remove pullies and crank triggers. DO NOT remove the 19mm bolt holding the front hub on the engine, this is part of the shortblock assembly and I require this to perform the rebuild.

Remove the small coolant line on the rear iron of the block carefully (the lower end is soft). It is not a bad idea to replace this hose which is hard to get to on the assembled engine.

Remove the knock sensor from the front rotorhousing with a large adjustable wrench…
Remove the oil pedestal housing with a 10mm wrench from underneath. Remove the oil pressure sending unit using a wrench on the hex adaptor screwed into the block. Remove the temperature sensor from the block with a deep well 12mm socket or a wrench.  This is easy to damage. 
Remove the flywheel nut, flywheel, and key on the e-shaft. Once the nut is removed from the flywheel, select a blank spot on it that is not near the ring gear, friction surface, dowelpins, or pressureplate bolt holes. Use a large hammer and strike one hard swing at a time until the flywheel is jarred off the shaft. This is about a 30 second operation. Leave the nut threaded onto the end of the shaft until the flywheel is loosened, and then remove them both. Use a smaller flat screwdriver to pry the key out of the keyway. IF you are unable to remove your flywheel, I can do this for you with the shortblock rebuild at no cost, it may cost you a few bucks extra in shipping weight.
Flip the engine over. Remove the motor mounts and brackets. Remove the oilpan and pickup. Be careful with the oilpan, as it warps easily, compounding it’s tendency to leak. I break the seal on the oilpan by using a fairly stiff putty knife hammered in between the block and oilpan, and then striking the putty knife on the side with the hammer to drive it around the mating surface to split the seal safely without bending the pan.
Rotary Resurrection - Tech Section
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