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How To:- 3S-GE to 3S-GE Engine Change

As I have found it is very difficult to find the information on how to carry out an engine change on the MK2 N/A engine, I have decided to carry out a Haynes Manual style guide for anyone who needs to do this job.

It is my aim to complete this stating all tools needed, torque loadings and costs involved so that anyone on here can do the work themselves without using a garage and being charged the earth.

This work is being carried out on a driveway not in a workshop......if I can do it then anyone can, just follow all the steps and photos (major piccy whore I'm afraid) below and it is as easy as that.

Step One

Park the car on the driveway giving ample room at the back of the car to allow access for the engine hoist at a later date.. remember that once you start this work the car cannot move.


Step Two

Open the frunk and remove the spare wheel and the plastic cover


Now with the battery on display, remove both the positive and negative terminals (10mm bolt, place the terminals into plastic bags and tape them closed, this is to stop the contacts inadvertently touching the battery.

Step Three

Removing the inspection panels and engine bay lid.

First open the engine lid to allow access.

Next remove the 4 retaining screws holding down the inspection panels, 2 are located on each panel. Next using a 10mm socket remove the earthing strap on each panel. refit the bolt in the hole to lower the chances of losing them later.

Pull the panels carefully towards the centre of the car to remove them from there mounts, then store them safely in a location that will become a collection of all the parts you have removed.

Next you need to remove the engine bay temp sensor located on the engine bay lid.

Mine was held on with tie wraps so i simply snipped them with pliers and removed the waste.

Once this has been achieved the engine lid is ready to come off, to do this there are 2 10mm bolts holding the lid on at each hinge.
TIP: It is a good idea to use WD40 first on any bolt that needs to come out as they can be rather stubborn and you don't want to shear anything.

Loosen the bolts but don't remove them all the way, work them out together. Once this is done with some assistance lift the engine lid upwards (careful not to scratch the paint) then put this with the inspection panels after putting the bolts back into their fixed nuts.

Note: WD40 always handy for jobs like these. (strut brace removal and refit will be covered later)

Now comes the fun stuff !!

Step 4

Air Filter Removal
Rather than write up what I have done as everyone has different filters, I feel it would be better to use other articles in the Know Your 2 section for this part PeteJ's article is of best use CLICKY

Step 5

Sorting out the coolant and heater pipes.

For this there are 4 pipes, 2 for the main cooling system and 2 for the heater assembly in the cabin.
3 pipes are located together under the throttle body these are the 2 heater pipes and one large pipe.
Once the large pipe (running across the picture, left hand side) has been removed, one of the heater pipes will become visible. the second pipe is located on the front of the gearbox. These are removed by a spring clip, using some grips squeeze the 2 lugs on the spring clip together and move the clip away from the housing, carefully remove the pipe from its hosing by wiggling it up and down.
Then repeat for the heater hoses.

Next move to the other side of the exhaust manifold and remove the other hose connecting there.

Careful as there will be a lot of coolant coming out, it may be an idea to put an old paddling pool under the car to collect the coolant in so it can be disposed of safely afterwards.

Step 6

Disconnecting the fuel lines.

CAUTION from now on there will be open fuel lines venting.

I don't need to say it but I'm gonna, now is not a good time for a ciggy.

There are 2 fuel lines, a feed and return. The return line is connected by a spring clip roughly where the main coolant/heater pipes are located. Use the method above to remove the spring clip and pull the pipe off.

For the feed line you need to locate the fuel filter, this is on the nearside of the car body low down and has a 17mm hollow bolt securing it in place

Carefully remove this bolt and washers, once the union is off replace the bolt and washers into the filter (this will be replaced once the engine is out).

Cap off the fuel lines if possible with bungs or plastic bags.

Step 7

Removing the oil.

This is where you need to get on the floor and under the car. Looking under the offside wheel, you should see the bottom of the sump and the 14mm sump plug undo this and have something to catch the oil in.

Leave this to drain for a good 10 minutes before refitting the sump plug.

Step 8

Throttle cable removal.

For this you will need a 12mm open ended spanner. Loosen the nut on the adjuster and pull the cable out wards and disconnect the end of the cable at the throttle body

Secure this part to the car body using masking tape.

Step 9


Starting with the ECU, open the boot and remove the carpet section covering the rear firewall. Small clips (pull to remove)hold it in place


Remove all the electrical connectors, you can see 3 in the bottom of the ECU

And 2 on the other control boxes.

Once these are all removed, push the rubber grommet out into the engine bay and pull the connectors through.

Unbolt the diagnostic port (12mm bolt) and the plug bank on the other side of the rear firewall (12mm bolt)

Next disconnect the vacuum hose and earth plug from the car body to engine these should just pull off.

Finally disconnect the engine bay fan connector from the drivers side vent.

Next locate the fusebox in the engine bay (rear bulkhead nearside)

Undo the 12V feed, lift rubber cap and undo the 2 10mm nuts then bag up the cable.

Next unplug the 2 white connectors, grasp the wires in your hand and tug the plastic retaining clip out of its location.


This now allows you better access to the coil pack. Release the king lead and all the electrical plugs you can find. there are still more connectors to undo but this will be done at a later point

Step 10

Exhaust removal.

For this section again it is better to use the Know Your 2 section and Poohbear's article on fitting a mongoose exhaust as it covers all outcomes. CLICKY

Step 11

Jacking the car.

I know this may be sucking eggs but hey.

For this you will need axle stands, a trolley jack (note: one is high lift) and wheel chocks (you wont be able to use the handbrake, so chock the wheel for safety's sake.

Initially to remove the exhaust, axle stands were placed on the sub frame (better point of contact).

Remove both rear wheels.

Step 12

Brake calliper and rear hubs removal.

For this you do not need to interrupt the brake lines, these can stay connected throughout the entire engine change.

Located at the rear of the calliper there are 2 17mm bolts, one towards the top of the calliper one at the lower edge of the calliper, these need to be removed (be careful not to spray WD40 on the brake pads or discs) cover the bolts in WD40 and leave to soak for a while before undoing them.

Once the calliper is unbolted ensure the handbrake is off and tap the calliper off the disc using a rubber or hide faced mallet. (pads will be replaced later) tie the calliper to the springs to take the weight off the brake pipe, tie wraps are ideal for this.

Remove the disc, this should just pull towards you.

looking at the sub frame you will see 4 suspension arms bolted into it (2 each side) these are the first section to be removed.

On the rear of the sub frame you will see 2 17mm bolts remove these

Once these are out you need to remove the front ones (engine side) these however are slightly bigger at 19mm and they can be tricky to get at

With these to rods disconnected the hub will rotate slightly.

Now locate the lower ball joint, you will find a castellated nut with a split pin, next to this, there are 2 17mm bolts remove these.

At this point there is now 2 bolts holding the hub in place, these are located on the shocker its self and they are 2 sets of 19mm nuts and bolts undo these and carefully remove the bolts out.

At this point you will need to have a breaker bar handy as you need to lever the hub away from the shocker. The only thing now holding the hub to the car is the drive shaft.

To remove the driveshaft grasp it firmly and give it a few sharp pulls to release it from its housing,

Have something to catch the oil from the gearbox or better still drain it beforehand using the drain plug (I forgot and this is the result) !!

Repeat this step for the other side.

Step 13

Sub frame removal.

First job here is to move the axle stands and reposition them under the sills, I tried to go for a point roughly in line with the 'B' pillar, thus allowing free access to the underside of the engine bay.

Now remove the 3 x 14mm bolts for the rear engine mount located in a triangle arrangement at the centre of the sub frame

Once this is loose remove the 4 17mm bolts located one on each corner of the sub frame.

The sub frame will now drop free, it may be an idea to use a jack to assist in lowering it.

As the frame drops free it needs to be rotated forward to remove the rubber exhaust mount, this just pops free and the frame can then be lowered to the ground. Once this has been achieved then the anti roll bar (ARB) can be removed from its mountings, 4 12mm bolts hold this in place, 2 on each bracket. Tie the ARB up out of the way. I tied it to each towing eye with wire (or tywraps) this stops the ARB fouling the engine when its removed.

At this point you are getting very close to getting the engine out of the car.

The next few jobs are again to be carried out from above.

Step 14

Disconnecting the front engine mount, clutch cylinder and gear linkages.

front engine mount and gear linkages in place.

At this point the best option is to disconnect the gear linkages. This is a simple task. pull out the 'R' clip, remove the washers and lift off the cable, repeat this for the lower one. once this is done you need to remove the cable from its mount. This is located on the front engine mount, they are held in place by a 'U' shaped clip which forms an interference fit locking it in place. using something suitable to lever this out and pliers to pull once its started to move, the whole cable assembly come free.

Next disconnect the 12V supply from the starter motor, normally a 12 or 14mm nut, however be warned that on some cars a replacement has been fitted and this will be a 13mm (possible the only one on the car lol) it is best to tape up the supply cable to minimise any risk of in advertent arcing.

Now on to the mount itself, using a 17mm socket and spanner (one for each end) remove the nut and bolt running through the centre of the engine mount.

Next remove the top bolt (14mm) located in the mass of pipework on the clutch cylinder connecting it to the back of the engine mount and gearbox, then remove the 2 14mm bolts located inside the engine mount (tricky to get to (tip: use a ratchet spanner as this is the easiest option.)

The clutch assembly should become free once the back (engine side) part of the mount is removed, again secure with cable ties to the car body.

And that's it, at this point the engine is ready to drop as it is only supported by the gearbox engine mount and the engine mount by the cam cover.

Step 15

Dropping the engine.

As I knew my engine was dead I wasn't too fussed about being careful, I have been told that this method works and I thought that as I am doing the mother of all How-To's I would use this method as a means to show people what is possible and the risks involved.

Using 2 jacks to remove an engine and gearbox (PLEASE use a hoist as this is not the safest option)

First of all I would recommend having some assistance from a mate or 2. Thanks to Justin and Sarah. I could not have done it with out you, (well I could but it would have been messy)

OK, position 2 trolley jacks, one on the lowest point on the sump and one on the lowest point of the gearbox. Extend the jacks until they have firmly got the weight of the car and engine then carefully remove the bolts holding the remaining engine mounts in place.

I would start with the cam belt end as you have to get under the car to find the 2 14mm nuts holding the mount on, these are located above the alternator belt (not the best piccy I'm afraid)

Then on the other side of the car remove the 3 14 mm bolts and the 12mm earth strap


With a strop attached to the inlet manifold and someone to support the engine during its descent, lower one jack a couple of inches, then bring the other jack down the same amount slowly and under control, checking to make sure there are no obstructions and or pipes/wires still connected.

Once the jacks are fully lowered, using a piece of wood (long and thick) lever the engine up and slide the jack out then repeat this process for the jack on the gearbox.

At this point you can breath again as you have got the engine on the floor you are nearly half way there.

Now the only issue you have is getting the engine and gearbox out from under the car. Again I used a method I was not too keen on but it proved a point.

Using a solid piece of wood (8 foot x 4 inch x 2 inch) place this under the car so it comes out either side of the car by the 'B' pillar. place a jack on either side of the car so the cup of the jack is in the middle of the plank and as close to the edge of the car as possible, as long as the jacks lift together and the axle stands are extended at each opportunity this should suffice

To enable the engine to be removed the rear of the car needs to be lifted until there is 30 inches of clearance (from the ground to the bottom of the rear bumper) Watch the front splitter !!

At this point the engine needs to be slid out, the easiest way to achieve this is to use a trolley or even a skateboard lol, however again to prove a point we used the same wooden planks as before to assist the slide of the engine with the strops repositioned and a little tug of war the engine slid across the planks and was free.



The only thing left to do now is lower the car back down so that it is more stable on the axle stands and to enable you to get in there and clean everything (coming in the next section)


PLEASE do not use this method as it is really not safe to do. PLEASE be responsible and think, I did this to show how unsafe it is and will be putting the engine in using a hydraulic engine hoist.

Step 16

Gear box removal.

TIP: Now the engine is on the floor it can be rather unstable, at this point having a, engine hoist available is recommended, this will take some of the risk out of the equation.

First thing to remove is the starter motor

Using an extension bar on the end of a ratchet handle and a 14mm socket remove the 2 bolts holding the starter motor in place remove any electrical connectors attached to the starter. There should be a brown plug located under the unit itself.

Once all connections and mounting bolts are removed gently tap the unit with a rubber or Hyde hammer as the units can bond with the gearbox seizing them in place.


The next phase is to disconnect any electrical plugs from the gearbox as these are connected to the engine wiring loom.

At this point it is better to start by removing the bolts at the bottom of the gearbox as you do not want to end up removing the last bolt and having the gearbox drop onto your arm.

There are 2 different sizes of bolts used to hold the gear box on 14mm and 17 mm

My tip would be to remove the 14mm bolts first, there are 2 located underneath the starter motor housing these also hold the black metal heater pipe in place

Once these are removed the pipe should also then become free, next work round the gearbox removing any other 14mm bolts, once all these are out repeat the process for the 17mm bolts remembering to work from bottom to top.




Metal heater pipe disconnected

At this point the gear box will come off it may need a little bit of jiggling (I would recommend having 2 people for this task as the gear box is quite heavy.

Once the gearbox is to one side you should now see the clutch assembly

To remove this there are 6 12mm bolts located round the outside of the thrust plate, again at this point it is not advisable spraying WD40 or any other lubricant onto the assembly.

Once these bolts are removed the thrust plate and clutch plate will be held onto the fly wheel but 3 locating studs, once the unit is pulled towards you the clutch assembly will be completely removed, it is best to store this assembly somewhere safe that is free from grease and dirt.

The final thing to remove is the fly wheel, for this you will need a 14mm socket and someone to hold the pulley connected to the opposite end of the crank shaft (where the alt belt runs onto), this will need a 20mm socket and a ratchet handle.

Remove all 8 14mm bolts, once these are out be careful as the flywheel is heavier than you would expect.

At this point congratulations are in order as you now have your engine out, gearbox stripped off it, and all that is remaining it to put it all back together again.

Personally I took the opportunity to clean the engine bay, gearbox, exhaust and engine lid, I took it a bit far by first using Gunk then T-Cut and finally Maguires three step polishes. I also took the opportunity to spray the bottom of the chassis rails in the engine bay with Hammerite stone chip paint as it was looking a little worse for wears in there.

The rebuild

NOTE: Due to the amount of photos currently in this How2 and the fact that people should know what work is required for the rebuild and where the components referred to go I will add the specific torque loading as well as any hints or tips that I used during this build.

Step 17

Gear box oil seals replacement.

I would strongly recommend replacing these seal as once they have been disturbed they are likely to rupture. The part numbers required for these are: T90311-35019 and they cost £11.15 each including VAT. Unfortunately they only seem available from Mr T themselves making a total cost of £23.58.

To remove the old ones simply leaver out the seal as there is nothing else holding them in.


Ensure you clean any dirt or old seal from the gearbox housing before fitting the new seal.

To fit it place it over the driveshaft output from the gearbox and gently tap it in using a small hammer or hide faced mallet making sure you keep them flat.


At this point your gear box is finished and the engine needs preparing for it to fit.

Step 18

Refitting the fly wheel and the clutch.

This section can be a bit fiddly. First you need to mount the fly wheel onto the engine, following step 16 in reverse starting with the fly wheel tighten the bolts lightly then using a torque wrench tighten the bolts in the following order,

Top left
Bottom right
Top right
Bottom left
Top right

This is called diametrically opposed and ensures that the part being fitted seats correctly. Once they are down quite tightly it is safe to torque them up, to do this first you need to set your torque wrench up to the correct setting.

For the fly wheel the torque setting is 80 ft-lbs or 108 NM

Tighten the bolt until you hear a click from the wrench at this point the bolt is tight enough and needs no more tightening.

Next refit the clutch making sure it is cantered before the torque load is applied to do this you can use a broom handle cut down to fit through the centre of the clutch plate or the correct tool which is how I would recommend doing it, however please note the one available from Halfords (laser) is not long enough to fit.

With the tool in place, place the thrust plate and clutch plate onto the lugs on the flywheel and tighten the bolts (again diametrically opposing) to the required torque
14 Ft/lbs or 19 NM.

Step 19

Next refit the gearbox using the same method as for removal, however at this point any item refitted should have copper grease applied to it this will stop any corrosion bonding the parts together which in some cases will cause damage or possibility of failure.

At this point it is best to ensure that all electrical plugs, vacuum hoses and ancillaries are fitted and connected correctly.

Step 20

Refitting the engine into car.

For the refitting I am going to use the correct tools rather than methods shown earlier (2 jack method).

First of all you will need a hydraulic engine hoist, decent strops (machine mart is a good starting point for these). And a couple of old skateboards or similar to roll the engine in place.

Place both the strops through the lifting hooks on the engine and attach the hoist to the centre point of the strops to ensure the engine is lifted flat. Lift the engine till you can place the 2 skateboards at the lowest point the sump and diff are ideal for this, and then gently lower the engine and gearbox onto the boards

At this point with the engine in the centre or the hoist resting firmly on the boards, move the strops off the engine hooks and place them through the rear towing eyes under the rear bumper of the car, use a thick blanket or foam (a camping roll mat is perfect) place this between the strops and the rear bumper to stop any damage occurring to your paint work, lift the rear of the car slowly using the hoist. It is important that as the car lifts up the axle stand are extended when possible just in case the strops fail.

Once you have enough clearance to slide the engine in push the skateboards with the engine on under the car and into the correct position making sure that nothing will get caught when you lower the car onto the engine.

Slowly lower the car to the down to a working level (lowest setting on the axle stands is suffice). Ensuring you don’t damage the engine by getting things caught.

Again reposition the strops onto the engine hooks and prepare to lift the engine into place.

Make sure the hook for the hoist is over the engine, if this is off the engine will swing as it self levels and could knock into the firewalls of the engine bay causing damage.

Slowly raise the engine into place, it is best to locate the right hand side (cam belt side) engine mount first as these are the trickier ones to get on but will help locate the engine better. Keep lifting the engine until the car starts to move, at this point put the 2 nuts onto the cam belt engine mount loosely and reconnect the bolts, earth straps on the gearbox engine mount once everything is reconnected tighten all the bolts on the 2 engine mounts up until they are tight.

Step 21

Repeat step 14, however please note, it is best to connect the clutch slave cylinder and the engine side of the mount first as it allows more room for moving the part into place.

Step 22

Refitting the sub frame, attach the rear engine mount (complete) first, once this is in place offer up the sub frame using 2 trolley jacks and place the 4 bolts into position and get them started. As soon as the sub frame is in place torque the bolts down to a figure of 83 ft-lbs or 113NM.
Next refit the 3 engine mount bolts that go through the sub frame and tighten to 57 ft-lbs or 77NM.

Step 23

Drive shat refitting, for this you will need 2 people as it is a little fiddly, first place the drive shaft on the floor either side of the car, clean any grease or dirt off the ends that go into the gearbox, while one person holds the drive shaft to the gearbox the other person needs to lift the hub and push it till it locates into the diff, once there a few hard pushes will seat it correctly. At this point it is recommended that you remount the hub into the shock absorber using the top bolt and loosely refit the bolts holding the bottom of the hub to the ball joints.

Once this has been done on both sides the lower suspension arms and tie rod ends can be refitted this is done exactly the same way as the removal, the front arms (tie rod end) need tightening to a torque of 76 ft-lbs or 103 NM, and the lower arms (rear bolts) to a torque of 98 ft-lbs or 132 NM. At this point tap the hubs with a rubber mallet to make sure they are seated correctly.

Now you can tighten the hubs in place correctly ensure both bolts are in the shock absorber to hub brackets (I personally put the bolts in front to back) tighten them down to188 ft-lbs or 255NM. And the ball joint to hubs need tightening to 83 ft-lbs or 113 NM.

Step 24

Following the reverse of step 12 refit the brakes and callipers, refit the wheels. At this point the car is very nearly ready to resume its position on the ground the only thing left to do is refit the exhaust again using Bobs How To on www.mr2oc.co.uk

Just before lowering the car to the ground one thing to complete is the reconnection of the fuel lines, coolant hoses and electrical connectors as was mentioned earlier in this write up.

Step 25

Gear box refill.

First of all for this you will need about 3 litres of 75-90w gearbox oil; Halfords sell this for £9.99 a litre or £7.99 with a trade card. You will also need a length of garden hose 1.5m long and a funnel, take off the drain plug and inset one end of the hose into the fill point the other end run up the engine and out of the top of the engine bay, attach the funnel to the end of the hose and slowly pour the oil down into the hose and into the gearbox until it flows out of the fill point, as soon as this happens remove the hose and replace the fill plug.

Step 26

Carefully lower the car to the ground so it is back on its wheels, there are only a couple of tasks left to do before starting the car this is replacing the oil and coolant.

Firstly top up the oil, after fitting a new oil filter get yourself another funnel and place this into the oil fill point.

Slowly fill the engine with oil, once you have a couple of litres in stop and wait for a few moments to let the level settle, check the level using the dip stick and top up as required till the oil reaches the full level.

Step 27

Coolant refill.
This is the part every MR2 owner hates, however it can be quite painless if you spend time and don’t rush it.

First thing to do is remove the filler cap in the engine bay, next go to the frunk remove the panel covering the top of the radiator and place one of your bleed tubes onto the bleed tap,

Unscrew the bleed tap until its open. Suspend the bleed tap from the frunk lock with a bit of string.

Repeat this process for the heater bleed point located above the battery

On the inside of the cabin turn the heater control to fully hot (this opens the system allowing coolant to flow through minimising the risk of an air lock later on).

At this point using a third funnel slowly pour the coolant into the system until the clear pipes in the frunk start to show coolant in them, keep pouring the coolant into the system until the coolant level in the clear pipes is at the same level as the filler neck, gently massage the pipes until all the air bubbles in the system have been removed. For now close off the bleed points in the frunk but leave the pipes attached.

Step 28

Starting the car for the first time.

First thing to do before firing up the car is to check everything that has been disconnected for signs of leaks and bad electrical connections, disconnect the king lead from the coil pack as this will stop inadvertent starting of the car. Reconnect the battery in the frunk making sure that all connections are tight and clean.

OK now comes the point where your heart is well and truly in your mouth, put your keys into the ignition and turn them to the point where you’re dash lights light up and all the pumps are working, if you see any fuel leaks stop and tighten the area of concern. If all is good try to start the car remember at this point the king lead is disconnected so it will not fire but will turn over, listen for any bangs, knocks, rattles or anything that is not right.

If all is good reconnect the king lead and try to start the car, once it fires let it run for about 30 seconds and shut it off.

Stand back with a whopping great smile on your face repeating the words “It lives, I’ve done it”

OK your not done yet, again check the oil as the level will have dropped and you have now filled your filter and the areas oil gets pumped to with the engine running, you will need to top it up again by checking the dip stick, once this is done start the car again keeping the heater on fully hot.

Once the engine is running remove the coolant cap and undo the bleed valves any air trapped in the system should start to flow round and be removed, keep topping the coolant up as it could start to disappear as the air is removed, keep the engine running until the radiator fans kick in this will show that the coolant system is up to temperature and the thermostat is operating correctly, with the engine running tighten up the bleed valves and remove the pipes replace the radiator cap stop the engine and top the expansion tank up to the full line.

Step 29

Refit the engine cover and inspection panels the car is now complete.

Step 30

Moving the car for the first time.

With the engine running pump the brake pedal as you have disturbed the system the will need resetting. With this done slowly move the car forward and then backwards to ensure everything feels correct.

After this there is only two things to do, the first is to give the car a dam good clean and polish.


The second thing to do is to go for a drive and enjoy your car again however a word of warning, please don’t just get in the car and drive it hard, run it in for a few hundred miles to ensure that everything is settled, re bleed the coolant system after 100 miles to ensure that all the air is out.
After this enjoy it !!


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