Rennlist - Porsche Discussion Forums - C4 engine and tranny drop

Here is the sequence in one list (detailed photos in the following posts):

luggage area plugs: battery ground (or remove both battery plugs, or kill switch in my case) and the workshop manual says the solenoid block plug too

engine bay:

5 plugs from intake region (not including AFM yet)

blower tube removal and vent line from tail lights and distributor

hall sensor plug and belt tension plugs

7 connections on left side of engine (O2 sensor, fuel return line, cruise control, white plug, green plug, etc.)

undo cover for fuses and remove 3 plugs - 2 from the fuse block and 1 small plug (not mentioned by workshop manual - maybe because my car is a 92?)

ignition cables from coils - remove from top of distributor caps

remove air filter cover to get access to power steering pump lines

remove fuel rail supply line (rearward line from the fuel filter)

power steering: drain reservoir (I just pulled off the lines and tried to catch as much as I could in a soda bottle - basically made a mess that dripped all over the ground - so lay down some cardboard, or even an oil pain if possible)

remove upper and lower lines from the power steering pump - one is a big bolt, one is hose clamped on

remove rear wheels (I removed all wheels because I’m changing my front brake pads, too - it’s also easier to jack the car up and down with the wheels off)

remove 2 upper driveshaft bolts from the interior of the car -
remove the cassette tray, or in my case, the little tray, and then remove the rubber cover and you’ll see the 19mm bolts below. Use a “ratcheting combination wrench” otherwise you’ll spend forever like I did using a regular combo wrench since you can only turn about 1/4 turn at a time.

disconnect the throttle cable at the gas pedal - you have to pull the gas pedal toward the rear of the car, then remove the 3 screws holding down the plywood cover, then unsnap the ball-end off the ball to free the cable. In order to do this, you have to unhook the small retaining wire, and actually remove it completely before the ball-end will pop off the ball. Once the ball-end pops off, unscrew it off the cable, and pull off the rubber seal so it can slide back through the tunnel unhindered.

remove engine undertray, tranny undertray, and the driveshaft cover which requires removing the cover over the fuel pulp, too. This is a bunch of 10mm nuts and screws, and a couple phillips screws for the tranny tray.

drain engine oil - the manual says you can leave the oil in the engine case if it’s not to be changed out.

undo lower oil line from the filter housing - I used two large crescent wrenches - one to brace with, and one to undo the nut on the line; once it’s loose with just a 1/4 turn or so, it can be undone by hand. I didn’t end up needing the $80 crows foot to do this - two big wrenches did the trick.

disconnect the driveshafts from the differential - lots of allen-head bolts to do, then set the driveshafts above the mating surface of the differential - that way things can be lowered with binding - tough to do on the right side due to the starter motor and differential slave cylinders

undo heater box air hoses from the heat exchanger

disconnect ground strap from tranny to body and also the ground wire from the starter motor bolt - this is attached to the body almost directly above the starter motor with a 13mm bolt - it can be reached easily with a really long extension on a ratchet.

disconnect 2 nuts on starter motor to remove the 2 big wires (red and black from alternator/battery respectively) from the big nut (13mm I believe) and the 1 small yellow wire from the small nut. Push the wires out of the way so they don’t catch when the engine is lowered

detach the clutch slave cylinder by removing 2 nuts and hang to the side (driver’s side)

remove rear sway bar by undoing at the drop links and the bushing mounts

undo shift rod attachment at the transmission by removing the 13mm bolt - it’s easier to pull the shift rod into the transmission (like shifting into 3rd) then you have room to withdraw the shift rod from the tranny

undo the 2 8mm allen head screws that attach the clamp to the central shaft on the front of the transmission to the central driveshaft. It’s hard to rotate the shaft so this might be better performed BEFORE removal of the CV joints so you can turn the driveshaft. Because I had already done that (CV joint removed) I could use a screwdriver in the seam of the central shaft clamp to rotate it. Once the 2 screws are removed, the clamp can be slid towards the front of the car, disconnecting the tranny.

pull out throttle cable from the tube in the floor - the plastic holder will need to be slid off the tube - I spent forever unscrewing it - but it slides off!

mount custom-made steel support for the driveshaft using the original bolts used from the driveshaft tunnel cover

undo the lateral slave cylinder bolts to the tranny, and unclip the retainer on the line to give the cylinder some free motion

undo the small single allen-head screw on the longitudinal slave cylinder - remove the 2-pronged fork by grabbing it and sliding it out. Once it’s removed the slave can be withdrawn - at this point just loosen it. Also unclip the fluid lines - there are 2 or 3 of them so the lines are free. The cylinder can’t be removed, or moved out of the way until the transmission mount is loosened to permit enough space to slide it down and out of the way - so don’t try yet!

undo rear right-side oil line in the wheel well - it helps to unclip the metal retainer to give the line some slack so you can pull it out. A little trick - push the metal line into the rubber tube to first break the seal, then the metal line can be easily slid out, separating the lines - it will drip oil so be ready to catch it.
undo the remaining 2 19mm bolts holding the driveshaft carrier to the transmission

put ATV type large jack under the engine as far forward, closest to the exhaust crossover pipe but not resting against it since that pipe sits pretty low and I didn’t want to crush it.

undo 6 17mm bolts holding the transmission crossmember to the chassis.

uncap the covers in the rearward engine tin to provide access for a ratchet to reach the rear engine mount nuts - these are 19mm nuts and on pretty tight

if the car is really high up, with very tall jackstands, the engine can now be lowered slowly. Lower it bit by bit, moving things out of the way as you go. When the engine is lowered about 2 inches, it is now easy to reach the Air Flow Meter plug, and there are 2 oil breather lines that need to be disconnected from the air intake boot. Also is 1 vacuum line to the right of the air cleaner assembly that needs to be unhooked. Now is a good time to move the differential locks out of the way. Keep track of the driveshafts (CV’s), and especially the differential locks as you lower all the way down. I used a second smaller jack to support the tranny because the engine is a little nose-heavy.

To lower the engine fully on the ATV jack, I needed to remove the primary muffler - which was really easy - just two allen-head screws, and 1 13mm exhaust flange to remove (I have a secondary bypass). This permits the jack to be lowered all the way without the muffler getting in the way.

I also could not remove the engine without removing the rear bumper. The rear bumper is easily removed by undoing the “shocks”. There are 2 13mm screws that hold the shocks in, and one 10mm screw on the back of the shock. Then there are a couple phillips screws and a few other sheet-metal screws to undo to free the rest of the bumper around the sides. You will need to remove the right-rear tail light to unplug the license plate light plug. Once unplugged, I removed the wires to pull it through the grommet easily. The bumper is now easily pulled off, and there is now about 2” of extra clearance to remove the engine. Mission accomplished!! ;)