How do you remove the old water pump on a 1988 Subaru GL SW?

Answer 1

Removing water pump from Subaru 1800cc engines.First a short disclaimer. I am not a professional mechanic. However I enjoy keeping my automobiles in top mechanical condition. I believe I can fix almost anything and have yet to find something I can't repair. (Though at times I have been known to spend more money fixing something than it is worth.) I have a long history with Subaru and can honestly say I believe they are very well engineered and a joy to drive. My current daily driver is a 1986 4WD GL wagon. Yes it is old, and yes I have had to replace a lot of parts. But it still runs well and gets pretty good mileage. Water pumps can be a bear to change on any Subaru. The 1800 series horizontally opposed 4's are not the easiest things to work on. But give yourself plenty of time and you'll find that it is not impossible to change a water pump. It just seems that way at first. (A good factory shop manual is a great investment for older cars. A generic repair manual from Chilton or Haynes is not a bad starting place, but cannot take the place of a factory service manual.) Many garages quote about 4 hours of labor to replace a water pump on a Subaru. If you are not a professional mechanic with lots of fancy tools, I would plan on it taking all day. The first 11 steps require getting things out of the way. You should plan on at least a couple of good hard hours to get to step 12, where you get to actually take the pump loose. This same procedure can be followed for most of the 1800cc and 1600cc engines. Subaru uses several different styles of water pump depending on the block model, and car. These steps are from a pump replacement on an 86 GL station wagon, with a non-turbocharged, carbureted 1800cc engine, dealer installed air, and manual transmission. However the procedure is similar for most models. You will need the following tools: A variety of open and box end wrenches and sockets in 10, 12, and 14 mm. Short and long socket extensions. A 22 mm open end wrench. A 22 mm socket and breaker bar. A pair of wide jaw pliers. Both flat and Phillips head screwdrivers. I also like a set of 10 inch Channel lock pliers to help remove stubborn hoses, and a pair of vice grips. A long reach magnet to retrieve dropped nuts is great to have around as well as a pair of long reach needle nosed pliers. Before starting, make sure the engine is cool. Use all the standard safety precautions, like wearing safety glasses, chocking the tires and disconnecting the battery. Subaru likes to pack a lot of stuff into a small package. So, if you do not use mechanics safety gloves I suggest you keep a supply of antiseptic hand wipes and adhesive bandages handy, as space is limited and you will probably come out of this project with a couple of scrapes and a busted knuckle or two. So, let's call this a 12 step program to Subaru water pump removal … 1. First drain the coolant. (Pets and even children have been known to drink antifreeze and become sick or die, so keep drained antifreeze away from children and pets.) 2. Just to make for more elbow room, remove the air cleaner and move any vacuum hoses that might get in your way. (If you have a turbocharger then try to leave as much as you can in place and work around it.) 3. Remove the rubber radiator hoses. (Do not worry about the steel extension tube that attaches to the pump. You can remove it later.) 4. Remove the battery. Since you will need to remove the alternator, go ahead and get the battery out of the way. This leaves a nice flat surface to lay parts and tools. 5. Loosen the alternator and remove the belts. 6. Remove the alternator. Lay it over on the empty battery tray out of the way, or disconnect it entirely. 7. If you have air conditioning, remove the AC compressor by removing the entire bracket. (Do NOT disconnect the hoses.) This is actually not as hard as it sounds. Once the bolts are out of the bracket, tie the AC compressor up out of the way. The hoses are quite stiff, so you will need a strong strap or cord to hold it. 8. Now you have easy access to the remaining hose and extension tube. Remove these. The metal extension tube can be reused if not too rusty, but all rubber parts should be replaced. (Especially ones this hard to get to.) 9. Now is a good time to remove the fan and fan clutch, (if your model has one) from the front of the pump. This is easiest to do by placing a 22 mm open end wrench over the shaft behind the fan, and using a 10mm box end wrench to remove the nuts from the studs. Don't worry if a stud comes out with the nut. (If your model has dual electric fans, remove the fan from the driver's side.) 10. Next you will need to remove the pulley from the front of the crank shaft. (It may be possible to get the pump off without removing the crankshaft pulley. See note * below.) Removing this pulley can be a job in and of itself. It takes a 22mm offset box wrench or socket and a breaker bar. Be sure the car is in gear and the emergency brake is set. You will need a stopper tool on the pulley to keep the engine from turning when you try to remove the bolt. You can sometimes pinch a belt around the pulley and hold it tight enough to hold against the torque. It really, really helps to have an extra pair of hands to help with this step. (Treat your help well. You may need them to get this all back together!) 11. Next remove the timing belt covers. To make this easier, take the oil pan protector plate off. You will have more room to get to the bolts off the bottom of the timing belt cover which, instead of being threaded, have NUTS! Without keepers! So you will need two 10mm wrenches or a wrench and a socket to get them off. All the fasteners on the top and sides are threaded making them painless to remove. (I have no idea why the ones on the bottom use nuts. Some engineer was probably laughing his head off when he designed this.) 12. NOW… Finally… At Last! You get to remove the pump. If you do not have a factory shop manual you will need to closely examine your pump to find the all the bolts. Generic repair manuals generally do not show good diagrams of the water pumps, so be careful to find them all. The most common pump has a total of 7. 5 go through to the block and 2 are for the timing belt cover. (If you have not already done so, I suggest you completely remove the timing belt cover. This will give you better access to the bottom of the pump and possibly any bolts hiding under there.) At this point removal is basically just a matter of removing all the bolts and removing the pump. Many times I have found that the pump will need to be bumped loose with a couple of sharp whacks from a hard rubber mallet. A block of wood works as well. (Do not strike the pump housing with a metal hammer and take care not to crack the pump housing. This would make it will be worthless as a core return when you buy the new pump.)

* Note: I have heard that you can sometimes take the bolts out of the timing belt cover and flex it enough to squeeze in a couple of fingers and a 10mm box end wrench and work the two bolts out of the bottom of the water pump. That not only sounds tedious but painful. A better option is to use a right angle drill to make a couple of ¾ inch holes in the cover just behind the bolts so that you can insert a 10mm socket. (You can flex the loosened cover enough to estimate hole placement close enough to drill the holes, but be careful not to nick the timing belt!) These holes should have been designed from the factory anyway. The engineers thought to put in a rubber plug over the timing hole. but not access holes for water pump bolts. (Maybe they thought it would last forever!) When you are done you can plug the holes with rubber inserts from a hardware store. (Another, really desperate answer is to loosen the bolts on the drivers side of the crankshaft and flex the cover enough to break it. I have actually seen this. The owner was able to bolt the cover back together as usual, cementing the broken edges together with Automotive Goop. It actually made for a good solid repair. However, I think he may have just been lucky that the cover broke the way it did. You should probably avoid this method.) In any case the OFFICIAL and CORRECT way is to remove the timing belt cover in its entirety. And the official method really does make it easier to access all the bolts easily. So now the pump is off and you can start the process of putting it all back together. Just install the new pump in reverse order. But while you have everything off anyway, this would be a good time to get the radiator out and cleaned and checked at a shop. Your new water pump won't do you any good if the radiator is plugged up. A good shop can boil it out and pressure test it, so you can be sure it will function effectively. Also remember to replace all the rubber, and install new belts. What's that? You don't think you need new hoses? Remember all the pulling and twisting you did to get the old hoses off? Well, all that abuse to those old dry rotted hoses will certainly have weakened them. And the older and stiffer they were, the more damage you will have done. Replace them. Trust me, you will save yourself a lot of trouble down the road. As for the belts, well they are not too hard to replace if one breaks. So inspect them closely. Bend them backwards and look for cracks. If you don't see any open cracks, they are probably ok to reuse. But if you see a lot of deep cracks, or the sides of the belt are hard, cracked, and shiny, I would replace them just to be on the safe side. Anyway, I am happy you have chosen to recycle your old car. Subaru's have a reputation for dependability and functionality, and if taken care of, will last almost forever. Well, they would last forever if they didn't rust out first. But that is another problem. So enjoy your old Subaru. May you share many happy miles together.