If you've grown tired of your engine's declining performance, inconsistent power, rough idle, exhaust smoke, knocking noises, rattles, and other maladies that plague worn-out engines, there are several things you can do. If you're impatient, your first reaction might be to sell the car for peanuts and pay big bucks for another one - new or used.
Another choice might be to rebuild the engine, or have it done for you. While a potentially viable option, your time and mechanical skills may be limiting factors.
Another, quicker and perhaps less costly option may make some sense when you give it a thought - and that's a replacement engine installation. You can go with a stock unit, or upgrade to a different, more powerful engine. Then again, maybe the rest of the car is worn out and the engine itself is worth keeping for some other project.
All these reasons are why a countless number of engines are removed from vehicles on a daily basis. If you've never done it before, the process may seem overwhelming. However, when you boil it down, nothing about it is overly complex. In this article, we'll review the general steps involved in removing a typical automobile engine to help you decide if it's a job you want to tackle. We're going the route of separating the engine from the transmission before removal, rather than pulling them both out together.
It's very important to call out that these are general instructions. We have done our best in the following steps to cover what you'll need to do on most cars. However, there will be major differences whether your engine is longitudinally mounted (most RWD cars) or transversely mounted (FWD). On some vehicles, it is recommended (and actually easier) is the transmission is pulled out with the engine as one unit. In very rare cases, the engine must be dropped from under the vehicle, which means raising the body (and we do NOT include that variation here). It is always recommended to reference a vehicle's repair manual along with our instructions.
To lift the engine up and out of your vehicle, you'll need an engine hoist and some related equipment found in our engine hoists and stands section. For a more detailed clarification of these items, see our related article What You Need When Rebuilding or Replacing An Engine.
Here are some other items we recommend:
- a. A thorough, detailed repair manual that will help you navigate through any odd vehicle-specific parts or procedures that couldn't be anticipated ahead of time.
- b. A level, paved surface to park the vehicle on while you work. NOTE: if doing this in a closed building such as a garage, be aware of how much overhead space you will need when raising the engine.
- c. A full complement of hand tools including wrenches, socket sets, screwdrivers, pliers, pry bars, and even a razor blade or two.
- d. Air conditioning tools if the vehicle is equipped with A/C.
- e. Masking tape, felt marker, and plastic bags for tagging, labeling, and storing parts as they are removed.
- f. A digital camera to capture images and videos of how things look before disassembly.
- g. Jack stands, a vehicle jack, and wheel chocks.
- h. Multiple drain pans for draining oil, coolant, and other fluids.
- i. Lots of shop rags.
- j. Rust penetrant for freeing difficult-to-budge nuts and bolts.
- k. Special wrench kit for removing fuel lines, a/c lines, trans fluid lines, etc.
If your vehicle is equipped with A/C, please know that it is illegal (and harmful to the environment) to vent refrigerant to the atmosphere. You may want to consider taking the car to a repair shop for the A/C system to be evacuated before you begin removing the engine.
Secure the rear wheels with wheel chocks, and jack up the front of the car so you can place jack stands under designated points on the frame. Give the car a good shake to ensure it's stable - you don't want it falling while you're tugging on things underneath.
As a best practice, you should remove the hood before you start. Contrary to how it may seem, this is actually a simple job that requires only a socket wrench to loosen bolts which hold the hood to its hinges. Make sure you disconnect any washer fluid lines that may be attached to the hood. And you'll need at least one additional person to help you hold and carry the hood as you remove the bolts and lift it off the vehicle.
Keep track of nuts, bolts, and everything else that comes off by putting them in zip lock bags and taping them to whatever items they were removed from as you go.
Disconnect Fuel Lines & Battery
Before you unhook anything else, we recommend starting with the fuel lines. On fuel injected vehicles (pretty much everything built since the late 1980s), it's essential for safety reasons to depressurize the fuel system before disconnecting any fuel system connections. Remove the fuse or relay for your vehicle's fuel pump, then start the engine and let it run until it uses up all the fuel in the lines and stalls. At this point, the fuel system will be depressurized and you can disconnect fuel hoses, pipes, etc.
Most vehicles feature quick-release style couplings at points throughout the entire fuel system. Unhooking these couplings isn't difficult if you've got properly designed disconnect wrenches. These wrenches feature a slotted opening so the wrench can fit over the fuel line. A flange on one end of the tool is pushed into the fitting to trigger a release inside the end of the coupling piece.
Once you've run the engine to do this, you won't need to start it again. Always disconnect the battery cables next.
If you've got a modern vehicle with crankcase ventilation lines that route excess fuel/vapors back to the fuel tank, don't forget to unhook those.
Tag All Hoses, Lines, And Wiring Connectors
As you remove each connector under the hood, it's a losing bet to think that you will remember how it all goes back together (ask me how I know). Take the time to tag each connector, using masking tape and a felt pen, as you take it apart. This is in addition to taking as many "before" photos as possible. Tag all hoses and wiring connectors with tape that you can write on - labeling where things normally attach to (you'll thank yourself later) before disconnecting them. Taking a short video of how everything looks before unhooking items may also prove invaluable.
Drain All Fluids
Drain the motor oil and coolant from the engine. And whether you'll be pulling the transmission along with the engine or not, consider draining the tranny fluid also. Don't forget to unbolt the transmission dipstick tube from your engine block, if your vehicle is so equipped.
If you won't be re-using the fluids, put them in containers that are practical and easy to take to a recycling center. It makes good sense to replace old fluids you've drained with new ones when things go back together later. Keep one or two drain buckets on hand under the vehicle because leftover fluids will seep and weep as you work - including out of the transmission when the engine is separated from it.
Disconnect Hoses And Lines
Now that fluids are drained, remove coolant hoses to and from the radiator in the front as well as the heater core in back. You also need to disconnect the automatic transmission hoses or lines that run from transmission to the radiator for cooling purposes. And assuming your power steering reservoir is bolted to the frame of the vehicle, disconnect any hoses running from it to the power steering pump on the engine. Be prepared to catch additional fluid that didn't drain out from other areas.
Evacuate The A/C System
Evacuate all the refrigerant from your air conditioning system. For more details on that procedure (and charging it back up later) along with the tools you'll need to use, see our article How To Use An A/C Manifold Gauge Set. After the refrigerant is discharged and the system is depressurized, unbolt the metal lines leading to the vehicle's compressor mounted on the engine block. (On some much older cars from the '60s and '70s, we have had some success with unbolting the A/C compressor from the block and, leaving the lines intact, swinging it out of the way. Doing this eliminates the need to evacuate and recharge the system.)
Remove The Radiator And A/C Condenser
If you have a small engine and a straight upward shot, it may be tempting to leave the radiator and A/C condenser in place behind the front grille. However, they can easily become damaged as the engine is moved forward and around during removal. It's better to be safe than sorry. It won't take much extra effort to unbolt and pull both of these items out now that the hoses and lines have already been disconnected.
For those with a van or select trucks, you'll probably need to slide the engine much further forward to get it out - requiring that any impediments such as radiators, A/C condensers, header panels, grilles, and even bumpers be removed.
Unbolt Exhaust System Components
The exhaust system needs to be disconnected from the engine. Here, you have a choice. You might need to disconnect the header pipe (down pipe) from the exhaust manifold, or the manifold itself (two on V-engines) may need to be unbolted from the heads. Check to see which is the better choice on your vehicle.
Exhaust bolts will probably have some corrosion around them, so apply rust-penetrating solution and let it soak in for a little while to help break things loose.
Attach The Chains
Once you've got everything else disconnected, attach the chains and hooks from your engine hoist to the engine block. Sometimes, hooks can be secured to special eyeholes that exist in the upper portion of the engine block. If these eyeholes are not present, look for threaded holes in the block designed to accept large bolts. These bolts are then used to install brackets which are attached to the engine hoist chains.
If you've got an older vehicle with a manual throttle linkage leading from the gas pedal, don't forget to unhook this. Newer vehicles will likely have drive-by-wire setups where a signal from the gas pedal is sent to the throttle body unit electronically. If so, you would have labeled this connector and disconnected it previously.
If you haven't done so already, remove the air intake assembly along with intake tubes or ductwork. And if other items such as your battery, battery box, washer solvent bottle, starter and alternator might pose clearance problems during engine removal, disconnect them and pull them out also.
Disconnect Motor Mounts
Before you start cranking on the engine hoist, you'll need to unbolt motor mounts which secure the engine to the frame or unibody. Most vehicles have two motor mounts, although some have up to four. The shapes and sizes of them can vary greatly. If you're not sure how to find all of the ones on your car or truck, a vehicle-specific repair manual will tell you where they are.
First, loosen the bolts that hold the mount to the engine by reaching down from above (you may need one or two long socket extension rods and a swivel joint). Then, remove the mount-to-frame bolts from under the vehicle. To get them fully out, you may need to raise the engine an inch or so.
Depending on vehicle application, many newer engines (especially transversely mounted) are equipped with an additional motor mount up high at the top of the engine. These will be easy to access and remove.
Since the engine is still connected to the transmission, you may need to loosen the transmission mount(s) enough to allow for some play. Raise the engine carefully at this point.
Separate Engine From Transmission And Lift
Once the motor mounts are out of the way, lower the engine back down a bit. The next step is to unbolt the engine from the transmission. First, it's essential to make sure the weight of the transmission is supported securely on a floor jack or jack stand. Once the connection to the engine is gone, quite a bit of support will be lost. Be careful not to position the support on the transmission fluid pan, as that can cause damage.
Start with unbolting the flywheel from the transmission's torque converter through an access plate, if you've got an automatic transmission. You may need to reach in with a screwdriver or other long tool to rotate the torque converter manually to expose all of the bolts. If your vehicle has a manual transmission, you'll be disconnecting the flywheel from the clutch in a similar fashion. Either way, the transmission needs to be in neutral with the emergency brake on and wheel chocks in place.
Once you've got internal bolts removed through an access hole, then you can remove any external bolts between the engine block and the transmission bellhousing. By removing internal bolts first, you ensure they don't get put under excess strain as the weight of the transmission shifts.
Check to see if your vehicle has a transmission heat shield. If so, unbolt it from the transmission housing. It may also be necessary to unbolt any gearshift lever linkage cables at the transmission. Freeing your transmission from these items allows it to be moved around more easily as you separate it from the engine.
Now you can begin to raise the engine again - but only a small amount at first. Odds are, you're going to see the transmission pulling up also because it may still need to be physically separated from the engine block. Depending on how much room you have to maneuver under the vehicle, a screwdriver or small pry bar can help get things apart. On automatic transmission cars, the torque converter usually stays with the transmission. Be careful to not let it slip out and hit the ground. On manual transmission cars, be certain that the transmission's input shaft is completely clear of the clutch assembly.
Using the engine puller, slowly raise the block a fraction of an inch at a time, while you check for clearance all around the engine bay. Once you are certain that everything is free and clear of obstruction, raise the engine as high as necessary to clear the body. Roll the engine hoist away from the car and be prepared to lower the engine in an area where you'll be working on it. We would expect that you will have an engine stand at the ready if you're planning on using one.
After you get your engine out, you may appreciate a browse through our Glossary of Engine Internal Parts and our Glossary of Engine External Parts that can be very informative and helpful as you move forward to the next stage of your engine project. But in the meantime, sit back and enjoy a refreshing cold drink - you've earned it!