This article is one in a series that have been released in conjunction with Wayne's book, 101 Projects for Your Porsche 911. The book contains 240 pages of full color projects detailing everything from performance mods to changing your brake pads. With more than 650+ full-color glossy photos accompanying extensive step-by-step procedures, this book is required reading in any Porsche 911 owner's collection. See The Official Book Website for more details.
Check out some other sample projects from the book:
The Porsche 911 engine is not one of the easiest to perform repairs on. The tight enclosure of the engine compartment makes it pretty difficult to reach in and access a lot of the fuel injection components. There are indeed a few things that can be done with the engine in the car (valve adjust, some fuel injection work, Carrera chain tensioner installation), but most major operations need better access. In these cases, the only thing to do is to remove the engine: a task that many conceive to be very difficult. The reality is that the removal of the 911 engine is not a difficult job: if you have the right tools and a little bit of the right knowledge, which I hope to provide here.
The car referenced in this project is a 1982 911SC. Other models will undoubtedly vary in parts and configurations, but in general, the procedure for dropping the engine is almost the same for all the 911s. The following procedure checklist outlines what you need to do in order to drop the engine:
Disconnect Battery
Remove Fuel Pump Relay
Empty Oil from Engine Sump
Empty Oil from Oil Tank
Raise Rear of Car on Jack Stands
Disconnect Hard Oil Line
Disconnect & Remove Rubber Oil Line
Disconnect Clutch Cable, Arm, and Helper Spring Assembly
Disconnect Reverse Backup Switch & Speed Cable/Sender wire from Transmission
Disconnect Heater Hoses From Heat Exchangers
Disconnect and Remove Shift Coupler
Disconnect A/C Compressor and Tie to Side of Car
Disconnect all Fuel Lines
Disconnect Main Engine Wire Harness
Disconnect Breather Hoses
Disconnect Accelerator Linkage Bar
Disconnect Cruise Control Cable
Disconnect Oxygen Sensor
Remove Four Nuts that Hold the Engine to the Transmission
Remove Engine Motor Mount Bolts
Lower Engine Down
Pull Engine Away from Transmission
Lower Down onto Cart and Remove
If you follow the procedure carefully, and check/double-check to make sure that everything is disconnected, the actual process of lowering the engine is not difficult. Different years will vary in what you need to disconnect, but in general, the procedure outlined above and in the photo series should give a clear indication of the steps that need to be followed. The general rule of thumb is to carefully inspect all the areas and components (lines, vacuum hoses, electrical connections) that connect the engine with the rest of the car. Cars equipped with Sportomatic transmissions have quite a few extra lines and hoses to worry about.
For additional information on some of the procedures, refer to the other projects in this book for more detail:
With this particular engine drop procedure, the transmission is left in the car. It is good practice to support the transmission with a jack stand after the engine is removed from the car, in order to decrease the load on the transmission mounts. If it is desired to remove the transmission with the engine, then a few extra steps are required. You need to disconnect the CV joints from the transmission mounting flanges, disconnect the transmission ground strap, unbolt the transmission mounts, speedometer cable, and also remove the rear sway bar if it gets in the way. Once this is done, the entire engine and transmission assembly can be lowered out of the car and then disconnected later.
When lowering the engine, it is very wise to have an assistant on hand. Not only can this person provide emergency assistance in case something goes wrong, but its also important to have an extra set of eyes that can watch and see if anything was overlooked during the entire process. The process of pulling the engine away from the transmission can be a little tricky. Make sure that your assistant is watching the surface where the engine and the transmission mount to keep tabs on the progress. When the studs on the engine case finally exit the transmission housing, the engine will become slightly unstable on the jack, so make sure that you have a hand free to steady it.
Keep in mind that you may need to jack up the car higher than you expected in order to remove the engine from underneath the car. It is quite common to lower the engine all the way down to the ground, only to find that you need to raise the car much higher to pull it out from underneath. Use a jack pad inserted into the cars jack hole and raise one side slowly at a time, gradually increasing the height of the jack stands placed under the torsion bar covers. It also may be useful to remove the rear valance panel, or even the rear bumper to gain additional clearance to pull the engine out from underneath.
Once you have the engine out of the car, its really handy to have a furniture cart to place it on. Make sure that you dont crush any of the oil lines or fixtures when you place it on the cart, and try not to let the engine rest on the heat exchangers. Use blocks of wood to make sure that the engine case actually rests on the cart.
There are a few things that you might want to consider doing to the engine while its out of the car. Its a very wise idea to spend a little money now, and do maintenance tasks that can only be performed when the engine is removed. Some of these include:
Replace the oil pressure switch. These often leak with age, and are pretty much impossible to get to on the 3.0L CIS (Continuous Injection System) or the 3.2L Motronic Injection engines. See Pelican Technical Article: Fixing Common Oil Leaks.
Replace the clutch and flywheel seal. It is recommended to inspect and replace the clutch disc when you have the engine out of the car. The flywheel seal, which can often leak, should be replaced as well. See Pelican Technical Article: Clutch Replacement.
Replace the CIS intake manifold hoses. The CIS fuel injection system used from 1973 ½-1983 relies on a strong vacuum seal. The intake manifold hoses should be replaced while you have access to the engine. See Pelican Technical Article: Tuning and Adjusting CIS Fuel Injection.
Replace the oil cooler seals. Although you can replace these with the engine still in the car, it is recommended that you tackle this job when access is much easier. See Pelican Technical Article: Fixing Common Oil Leaks.
Install the Carrera chain tensioners and adjust the valves. These two tasks can be performed with the engine in the car, but are significantly easier to perform with it removed. See Project 16 and Pelican Technical Article: Valve Adjustment.
Replace the pulley seal. Underneath the crankshaft pulley, the pulley seal can sometimes fail. If you have access to it with the engine out, its wise to replace it. See Pelican Technical Article: Fixing Common Oil Leaks.
When you are ready to reinstall the engine, the procedure is somewhat the reverse of the removal process with one caveat. With 1977-86 cars, when mating the engine and transmission back together, you must be sure that the clutch release fork mates properly in the groove of the throw-out bearing. Peek through the small hole in the top of the transmission case when you are mating it with the engine in order to make sure that the throw-out arm is properly set inside the groove of the bearing.
Figure 1
It is very important to remember to disconnect the battery negative cable prior to starting to remove the engine. The starter is connected to the battery at all times, and attempting to remove it when its live can be hazardous to both the car and you. Its also wise to remove the red fuel pump relay from its socket as well (See photo in Pelican Technical Article: Installing/Upgrading the 911 Front-Mounted Oil Cooler). If you decide to work on the electrical system of the car while the engine is out, and you turn on the ignition with the fuel pump relay in place, there is a chance that you could spill out gasoline from the disconnected lines in the engine compartment.
After the rear of the car is raised and the oil emptied, begin disconnecting the oil lines. The rear hard line connection (shown by arrow) may be difficult to loosen due to many years of rust and corrosion underneath the car. Be careful not to damage this line when you are applying force to remove it. Use two wrenches: one to turn the line, and another to hold the other end of the line steady. Do not apply force to the line itself, or you may end up damaging it.
The line that connects the oil tank to the engine needs to be completely removed (shown by arrow). Two hose clamps connect the line to the bottom of the oil tank, and the bottom of the oil filter. Inspect it carefully upon removal, and use a brand new one upon reinstallation if there are any cracks or if the line looks brittle. Have a drip pan ready, as excess oil in the line will spill out when you remove it.
The clutch cable assembly underneath the transmission needs to be disconnected. For 911s from 1976-1986, disconnect the clutch cable and remove the circlip that holds the small lever arm in place (shown by yellow arrow). Then remove the small coil spring from the lever arm (white arrow), and then pry off the lever arm itself from the shaft using a small screwdriver. The remainder of the assembly arm (red arrow) should now be able to be removed from the shaft. Be careful of the U-shaped helper spring (green arrow), as it is loaded pretty tight, and will spring back slightly when you pull the larger arm off of the shaft. See Project 10 for more information on the helper spring removal. For earlier 911s, the process is a bit simpler, as the clutch cable is connected directly to the throw-out arm.
Disconnect the starter electrical connections. Double check once again that your battery is indeed disconnected, as you can seriously injure yourself if your socket wrench touches the chassis while loosening the positive lead. Make a note of which terminal each wire is connected to, as it is easy to mix them up when reconnecting them.
The reverse backup light switch is hidden at the rear of the transmission, located right above the transmission mount bar (shown by arrow). Be careful when pulling out these wire leads, as the small brittle connectors can easily pull off of the wires. If your 911 is equipped with a mechanical speedometer, and you are removing the transmission, then disconnect this cable and pull it out of the way.
Disconnect the heater hoses from the heat exchangers. They should be attached to the top of the heat exchanges by hose clamps. Once the engine is out of the car, these should be checked. If they are original equipment, they probably need replacing. Newer high-temp aerospace hoses are now available as more durable replacements. See Project 43 for more information.
Behind the front seats in the center of the car is a small trap door that allows you access to the shift coupler. Remove this panel and disconnect the shift coupler by removing the small hex screw that attaches it to the transmission selector rod. Do not disconnect it by loosening up the 13mm clamp bolt, as you will have to readjust the shift linkage later on if you do. Disconnecting this coupler is a very important step, especially when dropping only the engine. As the engine is lowered, the transmission selector rod will rise up in the air. If the coupler is still attached to the selector rod, then you may end up bending the selector rod and damaging your transmission. Upon reinstallation of the coupler, be careful not to strip out the delicate aluminum threads that hold the screw. If the coupler bushings are worn or missing, then they should be replaced. See Project 37 for more details.
In the engine compartment, disconnect the A/C compressor from its mounting bracket, and place it over the side of the car. Do not disconnect any of the A/C hoses, as this will allow Freon to escape from your system and render it useless. Tie the compressor down with a flex-cord, and make sure that you place a thick towel underneath in order to protect your cars paint.
All the fuel lines that are connected to the engine need to be disconnected. On the 911SC, there are three separate connections. The fuel lines should be disconnected at the fuel filter and fuel accumulator, if possible (white arrows). Be aware that some fuel will spill out of the lines when you disconnect them, so keep any source of potential flame (shop light, etc.) away from the area. Prior to disconnecting the fuel lines, you may want to remove a few of the engine compartment heater hoses. The large plastic one that connects the blower motor to the fan shroud usually gets in the way of almost all tasks done in the engine compartment.
Disconnect all the main engine wire harnesses. On some models, there may be connectors that you cannot easily see without sticking your head inside the engine compartment. Feel around the sides and back of the engine to make sure that you have disconnected everything. For the 911SC, there is one wire set that connects to the chassis near the engine compartment fuse box, and one that connects to the front of the engine compartment. The backup lamp and starter connections need to be disconnected and pulled aside as well.
The oil tank breather hoses need to be disconnected. These are usually attached with hose clamps that are easily removed. There may be two or more, depending upon the type of fuel injection used on the engine.
Begin the removal of the accelerator linkage bar by disconnecting it from the bell crank located on the transmission. The other end of the rod should simply snap out of the fitting that is located on the top of the engine, inside the engine compartment (shown in photo), indicated by the yellow arrow. Access is usually tight in this area, and may require some effort to obtain the necessary leverage to remove the accelerator bar.
If your car has cruise control, disconnect the control cable from the throttle bracket. The cable is held on with two small screws (shown by arrow). Be careful not to drop these as you remove them: they can be difficult to retrieve. You also need to disconnect the two vacuum hoses from the control unit.
The oxygen sensor connector needs to be disconnected. Dont tug too much on the wire, as it might become separated, and new oxygen sensors tend to be expensive. If you wish to remove the sensor from the exhaust instead, make sure that you soak it in some WD-40 overnight, to make sure that the threads loosen up a bit. See Project 34 for more details.
There are four nuts that hold the engine to the transmission. The white arrow is pointing to the lower right one on the transmission. Removing these nuts will not make the engine less stable because there are four studs that exit the engine case and are inserted into holes in the transmission case. One or two of these nuts may be difficult to reach using standard tools. You might need to obtain some extensions and universal joint socket wrenches in order to obtain the right angle for removal.
The fourth nut that keeps the transmission and the engine together is also one of the nuts that holds on the starter. The nut is a 10 barrel nut, and requires a 10mm hex key or hex socket to remove it. This nut is not visible from any angle, so removal is especially difficult, and must be done by feel. The lower barrel nut that holds on the starter is similar to the one on top and does not have to be removed in order to remove the engine. If you drop down the engine slightly before removing this nut, you may be able to reach it from inside the engine compartment.
When you are ready to lower the engine, place the floor jack underneath the engine sump plate, and loosen the motor mount bolts located in the center of the motor mounts (white arrow). On the later cars, there are no nuts on the opposite end of these bolts: they are screwed directly into the threaded motor mount bar.
After the fan clears the rear bumper, pull the motor out away from the transmission. Do not lower the motor all the way to the ground unless it has been disconnected from the transmission, or you may damage your transmission mounts. When disconnected, lower the engine to the ground, and pull it out from underneath the car. If you need more room you can jack the car up higher, remove the rear bumper and/or valance, or remove some of the fuel injection in order to make the engine fit underneath the rear of the car.
Comments: following your insturctions for engine removal for my 1980 sc, got everything done but two parts 1. the large arm on clutch will not come off, it seems the whole shaft wants to pull out bottom of trany, any help? 2. i'm not removing trany so does reverse light conection have to come apart, this wire is a real pain to get to, any help?
November 20, 2011
Check out some other sample projects from the book:
