3SGuide

I have created this guide to supplement Antoni’s 3000GT/Stealth oil pump replacement guide. This guide will go into more detail than the guide found there and will give an account of my experience when I recently replaced my oil pump. I will give tips on how to avoid the problems I ran into along the way. First things first–most likely when you start, your car will look like this:

The first thing you will want to do is jack up the front of the car and USE JACK STANDS. I can not emphasize enough how important it is that you use jack stands as you will be working under your car for a good deal of the project.

Next, to make things easier and to allow more room to work down the road, unbolt the four bolts holding the AC line down and pull it up out of the way. There are two bolts located in the front and (2) 10mm bolts in back along the firewall.

Next remove the (4) 10mm nuts holding the cruise control box on, unhook the connection, and move the box out of the way, this will allow more room later on.

Next, you are going to want to remove the top (front and back) timing covers. There are (2) 10mm bolts holding the front on and (3) 10mm bolts holding the back on. In order for me to get the back cover off I had to remove the VICS motor. This is held on by 3 bolts which you need an Allen wrench to remove. After the VICS is removed the rear cover should lift right off.

Now to move onto the lower part of the engine. If you haven’t done so already, remove your front driver’s side wheel. Then you will need to remove the wheel well cover in front of the wheel (the one with the little slots in it) and the cover on the back of the wheel well. These are held on by a combination of bolts and these little grommet dealies that have a plastic screw that likes to get stripped. If you are having trouble getting these out, just grab hold with some pliers and yank them. Afterwards just replace them with the simple fasteners from Autozone.

You should now be looking straight at the crank pulley, AC compressor, and alternator belt adjustment pulley and bracket. You will want to loosen the 14mm bolt on the center of the pulley and then loosen the bolt on the top of the bracket to lower the pulley and relieve the tension on the belt. In the picture you can see the bolt I am talking about. After the belt is off and the pulley is removed, you can unbolt the 3 bolts holding the bracket on. Keep track of these as the top right bolt is a different length.

After you remove the bracket, it’s time to move on to the power steering belt. To remove this you will have to loosen the two bolts on the tensioner and then use a 1/2 inch extension to pivot the tensioner and remove the belt. After the belt is removed, go ahead and finish unbolting the tensioner assembly as it will just need to come out later to remove the lower timing cover. These bolts are difficult to get to and I found a 14mm box end wrench to be very useful.

Next it’s time to remove the alternator. Some say you can do the job with it still in the car (moved out of the way) but I couldn’t see how I would be able to do this. The easiest way I found to remove the alternator was to remove the AC fan. Unplug the two connections to it and then unbolt the (4) 10mm bolts holding it on. There are two on top which are easy and then two on bottom which are a bit more difficult. You will need to remove the plastic covers on the bottom of the car to get to these. After the bolts are out the fan will lift right out.

Now you should be able to remove the alternator. First unplug the connector from the left side, then flip the little plastic cover up and unbolt the nut holding the wire on, then finally there is a bolt on the bottom which holds the plastic piece to the alternator. There are 2 short bolts on top, and then 2 bolts on the side which bolt into the engine mount bracket. You can see the bolts in the following picture.

Now the alternator should lift right out. Put a piece of cardboard against the radiator to protect the fins from getting damaged. The alternator is a bit heavy so get it with both hands and wrestle it out.

Next you will want to remove the bolts to the AC condenser. You will not have to fully remove the condenser, just move it out of the way. On my car there were (4) bolts holding it onto the bracket, on some cars there are only 3. You can see the (2) top bolt in the picture. The other (2) bolts are easy to get to from underneath, (you’ll see them).

After you remove the bolts just rest the compressor up against the radiator. Now it’s time to remove the compressor bracket. There are (6) bolts holding this on. (5) of them are easy to see and one is basically invisible. These bolts are different lengths so keep track of where they go.

After you remove the compressor bracket I felt the crank pulley was the next obstacle to face. If you do not have the special Mitsubishi tool (a spanner wrench) have no fear, there are other ways of getting that bolt off. If you have an impact wrench, give it a go. It should come right off with that. Unfortunately not everyone has an impact wrench so the next best method is to get a 22mm socket on a 1/2 inch wrench, put a breaker bar on the wrench and rest it up against the frame as shown in the picture. Then, remove the spark plug wires from the distributer and give the starter a couple quick bumps. This should loosen the bolt rather easily. On mine, I had to give it about 20 bumps but it eventually worked so don’t get discouraged if it doesn’t go your way the first couple tries.

Editor’s note: Spray the bolt beforehand with PB Blaster. You can also use an electric or air-powered impact wrench.

Now that you have the bolt off the crank pulley you can go ahead and remove the pulley. You may have to wiggle it back and forth for it to come off, but IT WILL COME OFF, just give a wiggle and a pull.

Now you will want to remove the lower timing cover. This is a pain in the ass and Mitsubishi would have saved us a lot of time if they had just made the lower cover two pieces. In order to get the lower cover off you will have to remove the driver side motor mount and the bracket it’s attached to. You will also have to remove the power steering tensioner (which you should have done earlier remember?)

In order to remove the engine mount you will first need to loosen and remove the (3) 17mm nuts on top of the studs. You will need a breaker bar as these are torqued to about 75ft lbs. After these are removed you will need to jack the engine up just a bit. Place a piece of 2×4 on top of your jack so you don’t dent the oil pan. Jack up the engine a little bit. Now you can remove the nut on the right side of the mount that is attached to the bolt that goes through the mount. Then remove the 2 nuts on the left side. You have have to raise or lower your jack to pull the bolt that goes through the mount out.

Now you will have to remove the bracket attached to the engine. But OH NOES! There is a damn pulley in the way! You will have to remove the AC idler pulley first. This was tricky as I was unable to fit a socket wrench in there and the bolt is recessed so a box end wrench wont work. If you don’t have a VERY shallow 14mm socket you will need this:

This neat little devise will allow you to use a box end wrench with a socket, you will be able to get the pulley off with this.

Now that you have the pulley off you can remove the engine mount bracket. There should be (3) 17mm bolts left holding this on. The one on the top right is the reamer bolt. This gets removed last. The other two are easily reached from underneath. You will need the breaker bar again because these are torqued to about 55 and 80ft lbs. (sorry, no picture for these bolts, use your imagination or just look for them) Now you can remove the reamer bolt. Spray WD40 on it as you are removing it as it may be heat seized to the engine. keep track of the bolts as they are different sizes. Now remove the bracket.

There we go, we have all that crap off, just to get to the lower timing belt cover. There are (7) bolts holding this on. Once again Mitsubishi makes it difficult on us and makes them different sizes, so KEEP TRACK of where they go!

After the bolts are removed you will be able to take off the timing belt cover. I found it easiest to pull it out from the bottom.

Now you have the crank sprocket, timing belt, timing belt tensioner pulley, auto tensioner, and the elusive oil pump.And it should look like this:

This is where I want you all to pay SPECIAL ATTENTION. This will save you a TON of time. I repeat READ THIS CAREFULLY. Stand up and look at the timing marks on the cam gears. If they are not lined up with the marks on the head (or valve cover) line them up NOW. You will have to put the crank pulley back on but only hand tighten the bolt. Now you can turn the pulley clockwise or counter-clockwise to line up the marks on the cam gears and crank sprocket. Once the marks are lines up remove the crank pulley again. Now for the IMPORTANT time saver. (unless you are also doing your water pump) Take binder clips (bulldog clips, paper clips, whatever you want to call them) or zip-ties, and clip or zip-tie the timing belt to the cam gears. This will prevent the belt and cam gears from moving when you loosen the belt from the crank sprocket. If you enjoy wasting a ton of time resetting your timing then by all means ignore this step.

Once you have the belt secured on the cam gears you can loosen the 14mm bolt on the timing belt tensioner pulley. First to save more time and a trip to a vise, stick a pin or small Allen wrench into the hole on the auto tensioner. You may have to put some pressure on the pulley bolt to get the pin to slide in. Once the pin is in, go ahead and remove the tensioner pulley. Now remove the (2) bolts holding the auto tensioner on. And finally, remove the bracket the pulley attaches to.

After you remove the belt from the crank sprocket just move it out of the way and clip it or tie it up somewhere. Now you can remove the crank angle sensor (93 or 94+ i believe) move that out of the way up top somewhere.

Now you can remove the crank sprocket. It should “slide” off “easily”, or you can get a little flat head screw driver behind it and coax it off a bit. There is a little half circle “key” that holds it on (youll see it when you take it off) and the “ninja star” for the CAS behind it. Once the sprocket it off it should look like this:

Now go ahead and remove the oil pressure sending unit. You will need a 14mm open wrench for this. just let it dangle like in the picture.

YAY…if you’ve made it this far you are almost halfway done. Go take a break and drink some juice or something, maybe watch a movie and relax, put some peroxide on those knuckles, dont even bother with bandaids, they’ll just come off when you start working on it again.

Okay. Now its time to get that pesky oil pan off. There are a few things you need to remove first to get this off. 1. The downpipe 2. The starter 3. Transmission stay brackets 4. transmission cover 5. Right frame member 6. finally the oil pan.

First remove the (4) 17mm nuts which hold the downpipe onto the manifold. Once these are removed you may have to pull back on the downpipe to get the back pipe to clear the axle. tie the downpipe out of the way (youll appreciate the room).

Next you can go ahead and remove the starter. You will first have to remove the nut that is behind the red rubber cover, then you will have to unplug the connector (its small) on the solenoid. Now you can unbolt the (2) 14mm bolts that hold the starter on.

Now you should be able to pull the starter right out.

Next you will have to remove the (2) transmission stay brackets. One on front and one on back. There are (4) bolts holding each one on. (2) 14mm bolts on the bottom and (2) 17mm bolts on top. The front stay is easy to get off, just use a breaker bar because these bolts are TORQUED! The back stay is a little more difficult, I didn’t have a ratchet that could get the top bolts because of the axle so I had to use a 17mm box end wrench. Here are some pictures of the stays:

Now that the stays are out of the way you will have to remove the transmission cover. It is held on by (2) 10mm bolts on top (you’ll see them).

Now for the right frame member. It is held on by (6) bolts. two in front, two in middle, and two in back.

Give yourself a pat on the back. It is now time to remove the oil pan. First, DRAIN THE OIL! This is held on by (16) 10mm bolts. Remove these bolts (be careful to not let any fall into the transmission). Now you will have to pry on the oil pan lip to remove it. They say to pry on the corner by the starter but I couldn’t fit my pry bar over there so I just went with the corner by the pump. Don’t worry, you will bend the flange so just make sure to straighten it later. Once you get part of the pan off the rest will come off easily.

Lets take a look at what we’ve removed so far!

Now you can finally remove the oil pump. But first you want to remove the filter housing and oil pickup tube. The pump is held on by 5 bolts of different length (remember where they go). You can see the bolts in the pictures.

new pump


old pump and new pump

Notice in the picture of the back of the pumps, on the old pump in the upper left corner by the bolt hole there is a little piece of gasket missing.

If you look closely at the top right corner by the bolt hole, there is a tiny piece of gasket stuck there…Avoid the mistake I made and MAKE SURE YOU GET EVERY LAST BIT OF GASKET OFF!!! I somehow missed that and it cause a HUGE leak when I got everything back together.

When you install the new pump, it is okay to use a little bit of RTV sealant to hold the gasket in place. I just put some on my finger and spread it on the back around that “alley” that the oil flows through.

There you go, give yourself a pat on the back. You have installed your new oil pump. Now you get to reassemble everything in the order you took it off. Make sure to get all the old gasket off the oil pan and then use a bead of Permatex RTV (Ultra Gray) on the flange, making circles around the bolt holes. Practice mounting the pan first a couple times before putting the RTV on because the oil pickup is an obstacle.

Editor’s note: let the RTV get tacky for about 5 minutes before placing it. Do not tighten the oil pan bolts all the way until the RTV has dried for a few hours.

When installing the timing belt, it helps to rotate the crank sprocket one tooth counter clockwise, when you tension the pulley (using the special tool) it will tighten the belt and rotate the crank one tooth clockwise. Double and triple check that your timing mark on the crank is lined up and looks like this:

Now go back and double check the marks on your cam gears to make sure they’re still lined up. Make sure the pin in the auto tensioner can spin freely and is easily removed. If its not then you will have to adjust the tension on the belt until it can easily be removed and reinserted. The best way I found to do this if you dont have a 1/4 torque wrench for the special tool to pre-tension the pulley to 7ft lbs, just make it so the holes on the pulley are both on the top. This should allow the pin to spin freely in the tensioner. Now remove the clips from the cam gears, put the crank pulley back on, and rotate the crank pulley two full turns clockwise. check to make sure all the marks are still lined up and the pin can still be removed and inserted easily. If it can, let it sit for 5 minutes and then make sure it can still be removed easily. If it can, remove the pin, you’re done with that!

Editor’s note: For more information on the timing belt/60k service, click here

When I did the pump I also did my rod bearings. Since you have the pan already off, doing the rod bearings is cake.

Here you have a great shot at the bottom of your engine.

To get to the rod bearing you will have to rotate the crank so rods #6 and #5 (closest to the transmission) will be in their down position. You’ll know when you can see the (4) nuts close to each other. Now remove the (2) nuts on the rod cap closest the the transmission. You may have to give the cap a wiggle to get it to come off. Once it’s off you will have this:

You can see the cap is off and the journal is in plain view

If you want, you can check the clearance of the old bearing using some green plastigauge. I honestly didn’t care about the clearance of the old bearings since they weren’t too worn. But you SHOULD check the clearance on the new bearings to make sure they are in spec!

Once you have the rod cap off, slide out the old bearing, wipe off any oil, and slide the new bearing in. Now, to get to the top bearings you will have to slightly push up on the connecting rod. Then use the tip of a flat head screwdriver to slide the bearing around the crank. Take your new bearing, put some oil on the crank side ONLY, lay it up against the journal, and slide it around into position, then pull down on the rod to lock it in place. Now you can plastigauge the new bearing. Torque the buts to 38ft lbs. Remove the cap and check your clearance, you should be in spec (.0008 or .001 on the plastigauge package). Now just follow those steps for the remaining 5 rods, turning the crank pulley as you go to lower the next rods. Be sure to put oil on the side of the bearings contacting the crank before installing them.

Here are some pics of what my bearings looked like. They were worn, but not too bad.

old 6,5,4 bearings next to new

old #5 next to new

If you decided to stick around and do your bearings you can now put the oil pan back up. Make sure you remove the dipstick before installing the pan or it will get pinched in there.

Check all the torque specs in the repair manual. When you’re done you will want to remove the ECI fuse from the passengers side fuse box, reconnect the battery, and hold the car in the on position for 10 seconds. This will help prime your new pump. Install the fuse and start the car. Drive it around easy for the next few days and check for leaks just in case.

Dont forget to make sure all your plugs are connected, crank angle sensor, cam angle sensor, (2) AC fan plugs, starter plug, alternator plugs, cruise control box plug, VIC.

If you have any questions you can find me on 3SI.org username is DBLerman.

Written by: DBLerman (3si)
Editing by: wildarmz