Engine swaps are very common in the Honda world, but no one really talks about the specifics of how to pull or install and engine into our EF engine bay. I ended up putting a 96 civic DX motor (I had it laying around) in my new EF (it burned water) so I thought I would write an article about it.

Engine swaps are not hard, but they are time consuming. Don’t listen to some guy in some message board saying he did his B18C-into-EF swap in 8 hours, because he is either lying or has done many before. If this is your first one you should set aside a whole weekend at the very least (more if you have to swap a bunch of stuff from the old motor to a new long block or if there is a lot of wiring, that stuff takes a while). If you’ve done one before then you should know how long it takes you and reading this probably wont help you much. Oh, and have a buddy help you. Swaps are no fun and they take waaay longer if you are by yourself.

Some Tips before you start:

Things you’ll need:

Engine removal.

First drain the coolant and the tranny fluid. You don’t have to but if you don’t the swap will be really messy instead of just a little messy. The coolant comes out of a small butterfly plug on the right (pass) side of the radiator. The tranny fluid (assuming manual) comes out of a plug on the bottom of the side of the tranny, it takes a 3/8” ratchet to loosen (no sockets, just the 3/8” square).

After the fluids are drained I like to unhook all the crap on the top of the motor. I just go around and find everything that is would keep the motor from coming out and unbolt or unhook it. But for you who need to know everything before you start (I’m like that) I will try to remember everything that needs to be unbolted.

On top:

- Take out the intake tube and the top half of the air box. Easy to do.

- The battery, battery hold down and battery tray need to come out. The tray comes out with 3 or 4 12mm bolts. There is one on the side of the frame rail so remember to get that one.

- Take out the radiator and fan(s). If you don’t have AC this is really easy. Just take off the 2 upper radiator mounts, unhook the big hoses from the motor, unhook the fan (plug on the bottom passenger side of the fan), and pull it out. It’ll probably still spill out some coolant even if you drained it. Deal with it. If you do have AC it’s a bit harder. You have to unhook the harness from the 2^nd (driver side) fan. It snakes around the normal fan and has the fan plug on the driver side of the radiator. Then you have to unhook the hoses and pull the radiator up between the car and the stupid AC lines. They are hard lines and you will fight with them.

- Unhook the heater hoses. One goes from the firewall to the intake manifold and the other goes from the firewall to the side of the head right under the distributor. I usually keep the hoses on the motor and pull them off at the firewall.

-  Unhook the engine harness from the car. There is a big white plug and if you have an Si or HF, a green plug into the resistor box as well, on the driver’s side and 2 plugs on the passenger’s side. There are also 2 black wires that go from the harness into the underhood fuse box. Unhook those 3 plugs and also open the underhood fusebox and take out the 2 phillips screws holding the 2 wires. One of those wires frees up the positive battery cable harness (goes to starter too) which I like to take off with the motor. In addition to the plugs the engine harness will have a couple of steel tie-towns that are bolted to the body of the car. Take those out with your 10mm.

 

- Unhook the grounds. There is one that goes to the clutch cable bracket and one to the valve cover.

- Take out the speedo cable. It goes into the tranny just on the drivers side of the rear mount. You have to pull up the rubber cover and take out a little clip on the side of the speedo drive. Then you can pull the speedo cable out of the speedo drive thing in the tranny.

- Unhook the throttle cable. Take it off at the TB.

- Unhook the clutch cable. Unhook it at the tranny.

- Unhook the fuel lines. First, open your gas cap, then loosen the little bolt on top of the right fitting on the fuel filter. This will relieve the pressure in the system. If you don’t relieve it you could spray fuel all over. I’ve done it. I even got some fuel in my eye. It fucking sucked. After the pressure relief, take off the right fuel filter fitting. It takes a 17mm end wrench and is usually on really really tight. You also have to unhook the fuel return line. It comes from the driver side firewall and goes into the driver’s side on the intake manifold (in the fuel pressure regulator). I usually pull off the end on the motor and leave the hose in the car.

- Unhook the vacuum lines. There is a red line that goes between the IM and the canister, there’s probably a few that go from the IM to the Map sensor and purge control valve(s), and there is the big one from the brake booster. Remember or record where they go.

- Take off the header/exhaust manifold. Well, you don’t have to but I always do. It makes things easier. You might want to wait, though, until you get to the under car stuff so you could at least take off the nuts that hold it to the head.

- Take out the front mount. It has one 17mm bolt that holds it to the x-member and two 14mm bolts that bolt it to the tranny. It should be very easy to take out as there is no pressure on it.

- Take out the rear mount bracket. Again, you don’t have to but It makes the engine come out much easier. There are 3 17mm bolts holding it to the tranny and then one going through the mount. This one has pressure on it so it will come out a tad harder than the front mount.

 

Now that you are done with the top it is time to move on down.

Heres what mine looked like when I was done with the top:

 

On the bottom:

- Take out the axles. Loosen the 32mm axle nuts, for this you will need a breaker bar or a big cheater bar. Then I, doing one side at a time, jack the car up, take off the wheel, separate the lower balljoint (easier said than done sometimes), take out the bolt that holds the shock fork to the lower control arm (17mm), and move the fork so that you can get the skinny part of the axle through it. It is as simple as it sounds provided you can get the lower balljoint separated. To physically get the axle out you have to pop the inner CV cup out of the tranny (I use a pickle fork. I put the fork end between the tranny and cup then give it a quick jerk). DON’T just pull on the axle with out it separated from the tranny or you will pull the inner CV joint apart. The only way to fix that is to change the boot.

- After the axles are out I like to put the suspension together so I can roll the car around. Put the shock fork back on the LCA and the balljoint back together, then put the bolts/nuts on hand tight. Bolt the wheels on and the car will roll nicely.

 

- Unhook the shift linkage. The shift stabilizer bar bolts to the tranny with one long 12mm bolt. The actual shift rod is held to the tranny with a roll pin and is a bit of a pain to get out. Roll under the car and find the little rubber popoid looking piece where the linkage connects to the tranny, this is where the roll pin is. Pull the rubber back toward the tranny and it will expose a clip. Take the clip of and you should see the roll pin. Bust out your BFH and punch of choice (I use a ¼” socket extension, which has an OD of .32”, but a punch of the correct size works better) and go to town driving it up and out of the linkage. After the pin is out, the linkage slides right off.

 

- Unbolt the exhaust. Unbolt it at the flex joint (where the bolts with springs are). If you are taking the header out at this point there are a few other bolts/nuts that hold it to the block, so make sure you find those.

After all that, the engine will be ready to come out so you will need to bolt a chain/rope to it. On the drivers side front of the head there is an unused threaded hole which accepts a 14mm bolt, this hole is pretty much the universal motor-pulling hole:

 

 

Once the chain is on there and it has tension from the picker you can unbolt the left and right mounts from the chassis and pull the motor out. It’ll probably leak coolant so be ready. Then the motor is out! Yay! Dance around or take a break or something.

Engine Installation.

First you have to prep the engine bay. Clean it now! You will be able to get spots you would never reach with the motor in. If you are putting in a B-series motor you have to make a dent in the driver’s side frame rail just below the shock tower for the alternator. Your mount kit should have pictures in the instructions for the dent. After you make the dent you might want to paint the bay because the BFH will take off paint.

Next comes the engine prep.

B-series specific prep - As far as mounts go, I only put the driver side one on. The rear mount bracket and tranny mount just get in the way. If you are using a 3 mount kit (hasport, place, etc.) you might want to cut out the front mount bracket on the front crossmember. That thing has always given me trouble cause it hangs up on the “bell-housing,” so now I just cut it out with a porta-band (hacksaw for you masochists), or take out the spot welds with a spot weld drill bit (huge pain to use, but better result). Also, make sure your alternator belt is on. If you made your dent too small you may not be able to put it on without a LOT of trouble with the motor in the car.

D-series specific prep – I leave both side mounts on. These motors are smaller and they hang up less when installing. The rear mount bracket still gets in the way so leave it off. 

Put the biatch in!

B-series specific – To be honest I don’t know how other people do this. I haven’t ever seen anyone but me do a motor swap so these are my techniques. If you know of a better way then let me know. So here’s what I do:

- Lower the engine down as far as you can with the tranny lower than the rest (of course with no tranny mount). The tranny will slip under the right mount bracket and lower than the right frame rail. Don’t worry about the left side. As long as it is not hung up you are good.

- Put the right (tranny) mount on. The tranny should be considerably lower than the bracket so there will be room. Tighten the mount bolts too. With the billet aluminum mounts (hasport and probably others too) one of the bolts is sort of hard to get to because it is right under part of the mount bracket, so have patience with your end wrench.

- Raise the engine into position. The left mount will probably be close to bolting up, so I always get that one hooked up first. Raise up the engine and put the bolt through the tranny mount. Don’t tighten the mount bolts yet.

- Install the rear mount bracket. Maybe it seems weird to install this now with the engine already in, but for me it has always been easier. At this point the engine will very easily rock back and forth, so use this to your advantage as you are wiggling the bracket into place. You might need to take out the intake manifold brace (from back of block to bottom of IM), but probably not. But I haven’t ever had to. Once its in place, put all the rear mount bolts in and tighten all the other mount bolts.

D-series specific – Its really just the reverse of the removal.

- Lower the engine down so the right mount is below the right mount bracket.

- Bolt up the left mount.

- Raise the engine and bolt up the right mount.

- Put the rear mount bracket in.

- Put the front mount in.

- Tighten all the mount bolts.

 

Now that your motor is in all you have to do is hook everything back up. If you want, you can go through the removal steps and connect everything that was disconnected.