Notes on replace water pump 1991 318i (E36)

This is just the way I replaced my water pump. Anything that worked for me is not guaranteed to work for you. I've included a few photos that turned out and will make more and better photos on my next project with the car.

THE BEGINNING...
My car started to make a little whining noise somewhere in the engine compartment, but I couldn't see or hear where it was coming from. I thought at first that the alternator might be going or the air compressor or maybe the power steering pump. I used a wood dowel to listen to each device but couldn't be sure. So I let it go for a few hundred more miles. Of course the noise got louder to the point where people on the street would turn their head to see what the heck was coming down the road and my kids started to comment that they could tell when I was coming home 10 miles before I got there. To me it didn't sound all that bad. Shortly after this I noticed that I was loosing coolant and then I realized that the water pump had gone.

So I ordered a pump from the local auto parts shop and thought that the $100 price tag was a bit high. Did a little Internet shopping and found a few different styles that ranged from $25 to $125. It seemed that I could get either an OEM, or remanufactured, or a knockoff pump. I figured that I would just bite the bullet on this one and get the pump locally. Oh yeah, the dealer wanted $168 so that was out of the question. I ended up getting the water pump from the local auto parts shop for $86 including tax. The pump it turns out was made in Germany. Apparently there was no core charge for this pump; it wasn't until later that I figured out why. So where do they get these remanufactured pumps from??

FIRST TWO HOURS…..
Got a few hints from a few good articles off the Internet again. Don't want to mention names, but if you search for "technical article bmw 318i water pump replacement" some good stuff comes up. Thank-you Wayne…..

I removed the fan shroud from the radiator to give me room to move in. Just a couple of plastic rivet fasteners needed to be pulled out. Pulled the shroud up and broke a large chunk out of the bottom of it. I later tried to repair it, but then the next chunk broke off. As the car gets older the plastic gets more brittle it seems.

Photo Details
"A" - Where the fan shroud would be if I had taken the photo before removing it.
"B" - The fan blade assembly.
"C" - Water hose that needs to be removed at the thermostat housing and loosened at the radiator end then swung up and out of the way.
"D" - This is bleed screw that can be loosened to help with draining the coolant from the upper hose from the engine. The actual radiator drain is at the bottom of the radiator on the same side.
"E" - Radiator cap... duh!



The radiator didn't need to be removed since the engine is only a 1.8 liter.

Next, the fan blade needs to come off. In my case it required a 32mm thin long open-ended wrench. Most auto parts shops will lend you this wrench if they have one. In my case all eight places I called had them for domestic cars and trucks, but nothing narrow enough that would fit a BMW 318i. I ended up getting a long open-end adjustable wrench that would just squeeze between the thermostat housing and the fan blade. Remember that this is a left hand thread and that it should only take a sharp smack on the wrench handle to loosen it. Don't miss….. Once you get the fan loosen just spin it off.

It's also good to loosen the four bolts on the front of the water pump drive pulley while the belt is still on.

The main drive belt can now come off. Make sure that you make a photo or a diagram of the path of the belt. You don't want to be guessing later. Also look for where your belt tensioner is. I had the hardest time fining mine. If you look at other internet photos, you will see that there can be a few different flavors of the thing. Find yours first….. it will save some trouble later. Mine is a tube with a spring that slides up and down in it. The tensioner pushes up against the bottom of the tensioner pulley. There's a spot that you can use to pry down on the bracket that holds the tensioner pulley to the front of the engine. This compresses the spring and allows for the belt to slide off. I found out later after wiping some of the crud off the engine that there is a small hole that could be used to keep the tensioner down making it easier to put the belt back on after.

You will notice that all of the photos have a lot of oil and dirt build up on the engine. I had the BMW dealer steam clean this engine about two months before I started this project. I have a timing gasket leak and was hoping that I could locate it at the time, but no luck yet.

Photo Details
"F" - Oil filter canister, just as a reference.
"G" - Top idler pulley. Don't undue the bolt! Normally there is a cover over the bolt, but I removed it, because I thought that the bolt was used to loosen the tension. WRONG.
"H" - Water pump pulley.
"J" - My tensioner actually pushing up on the idler pulley "G" and down on the idler pulley "K".
"K" - Bottom idler pulley. Again No need to remove the cover to expose the bolt because nothing needs to be done with it.



Photo Details
Another view of the tensioner and idler pulleys.
"L" - Top idler pulley.
"M" - Bottom idler pulley.
"N" - bottom of the tensioner that contains the spring that twisted out and caused me some grief. This photo was taken after I removed the tie wrap and put the tensioner back together.
"P" - Tensioner that fell apart when I removed the belt.



You can leave the air compressor belt on unless you plan to change the drive belt (or the air compressor belt).

Once the drive belt is off just drop it down over the air conditioner belt.

Now that you loosen the four bolts on the water pump pulley it's easy to remove them. Keep the bolts and the pulley in a safe place. The pulley looks to be made of a high impact plastic.

Time to remove the coolant from the engine and radiator. I loosened the radiator cap and put a pan that can hold a few gallons under the drain plug. The drain plug on my radiator is located straight down from the radiator cap on the bottom of the radiator. Mine is blue in color. A #3 Philips screwdriver opens it nicely. One or two turns are enough. There is also a black bleeder screw on the top of the radiator that can be loosened in the same way to speed up the coolant removal. Make sure that the antifreeze drains into the pan and close the drain when you are done. If you reuse it, strain it first, in case it washed the dirt out of the pan or off the bottom of the car. I replaced the old coolant with new and brought the old stuff back to the auto parts shop.

To give you a bit more room you can remove the top radiator hose from the thermostat housing and set it to the side. If the radiator drained properly then there should be nothing in this hose.

Now you have a clear view of the old water pump. Again mine was the type that slipped into a round bore in the engine and had an o-ring for a seal.

Photo Details
"R" - Bottom of the thermostat housing. Just for reference.
"S" - I had already taken the bolts and machine screw out at this point and broke the top jacking point off.
"T" - Actual water pump with a few hammer marks.
"U" - Indicates where the jacking points would be. You can still see the screw in the bottom jacking point before it fell off.



There are four bolts holding the water pump into the engine. Three short hex bolts and one long hex head machine screw. The long hex head machine screw may require extra work in getting it out. Use some penetrating oil on all of them, tap them a little and wait a bit. Last thing you want to do is to break any off. While you have the penetrating oil out spray a little around the water pump edge that mates with the engine and give the end where the pulley was attached a smack with a rubber mallet as well. Once you get all three bolts and the long machine screw out of the water pump casting, the water pump will just fall out….. right?

THE FUN BEGINS…..
I have never had so much trouble in my life with removing a part from a car as to when it came to removing this water pump!!! If yours comes out easy, be grateful; otherwise be prepared for some work.

It could be that I didn't follow the instructions to the letter or it could be that my water pump was seized after being in place 15 years without a coolant change. Maybe they all come out this way when they get this old.

It was suggested in one article to give the water pump a tap with a rubber mallet to loosen it from the engine. I did this and nothing seemed to happen, so I tapped it again a few more times; still nothing.

Another suggestion was to use the two threaded holes in the water pump casting to jack the pump out. The method was to tighten two long bolts (3 inch) into the two jack holes in the casting. Just a little at a time, then back them out and then smack the water pump again with a rubber mallet. Tighten the two bolts back down again, this time a little more, back them out and smack the pump again. After the third time I had two bolts with parts of the casting attached, broken off sitting under the car.

Photo Details
"V" - This is a very import piece of wire. The sensor that it connects to measures the location of your cylinders and if you break this your engine will not start. Make sure it stays where it's suppose to! Mine had popped out and was rubbing against the main belt.
"W" - Broken jack point on the water pump, plus some other missing pieces.
"X" - Yes the air conditioner pump belt needs replacing, and so did the drive belt.



That's when I stopped using the rubber mallet and went for the 2lb hammer and gave it another smack. This pump was not going to come out…..

THE NEXT HOUR…..
I spent a few more minutes calming down and made a coffee. Looking again on the Internet I found a fellow who made an extractor that would pull the pump from the front, but used the timing chain covers as a pressure point. It's a good idea, but I didn't want to break the timing covers. I did come up with another idea though and that was to use a 1.5 inch square tube 3 feet long as a lever attached to the front of the pump via the pulley flange maybe rock the pump out of the engine. This ended up bending the square tube and got a few neighbors out of their houses to come see what I was doing. The general consensus was, "I should bring it into the shop and have the experts work on it." I told him that person he was probably right.

After a mild discussion the neighbors, they went on their way. That's when I got my electric drill out and started to drill the water pump casting. Fifteen minutes and two quarter inch drill bits later I had removed enough material from the water pump to get a large slotted screwdriver into it. After much wiggling (of the pump) it moved! A vise grip on the front of the casting then allowed for it to be turned a little. At this point it came out. After looking into the bore hole, in the engine, I didn't see really what was holding it in.

Photo Details
This is where I started to drill the casting of the water pump. Make sure you angle the drill down into the pump and not up into the engine block.
"Y" - The first hole on the left was where the long hex machine screw was removed. The next hole is where one of the hex bolts was removed. The engine looks nice and clean under where the jacking point is.
"Z" - This where the bolt for the jacking point pushes against. You can see that it left a good indent. It's possible that I turned it in too tight before backing it out before hitting it with the hammer.



Photo Details
"AA" - I continued drilling around the pump not realizing the mess I was creating.



Photo Details
"BB" - The first drill bit broke here and I thought that it might of dropped into the engine.
"CC" - This is just a reminder for me that I have to use shrink tubing on the wire because the belt actually touched the wire at sometime in the past. You see the insulation split near the air conditioner pump belt.



Now for the cleanup, make sure that you get the bore hole clean and remove any debris from around the opening as well that may fall in while installing the new pump. I used a brass wire brush the seat surface where the new water pump would contact. I also cleaned out the threaded holes where the bolts go back in. Get some white lithium grease ($2) and rub it around the o-ring. This makes for an easier install and can help with the next removal if ever. Use new bolts and screw if possible and look up the torque spec for them.

Photo Details
"DD" - Getting the bore clean again was not that difficult. I used a few paper towels and a stiff brass wire brush to clean the bore. A wet/dry shop vacuum was used to remove the metal flakes from the rest of the engine area. I also wiped the oil off with varsol.



Put the water pump in making sure it the right orientation. Push it in as far as you can by hand. Put the bolts and screw back in by hand and tighten them hand tight. Slowly turn the bolts and screw back in a little at a time tightening opposite sides first making sure not to use any force. The new water pump will push the o-ring back in to the engine a little at a time. Once the pump is seated you can torque the bolts and screw up to spec. Take your time and check the torque twice. I've stripped enough threads and broke plenty of bolts in the past to ensure that I follow my own advise..

Photo Details
"EE" - New water pump and pulley installed. New main drive belt installed. Yellow thing is the thread protector that you remove when you re-install the fan blade assembly.
"FF" - Air condition pump belt waiting to be installed.



Install any hoses that you had to remove and while at it check the clamps on the hose you can get to. I ended up re-torquing the hex bolts on the timing chain cover and found three of them loose. Maybe this will solve my current oil leak?

Fill up the radiator with whatever you use and if you can do a pressure test, be my guest. I don't have the equipment, but again the auto parts shop did (I learned later). Either case check for leaks. If none found (most likely) then remount the water pump pulley and tighten the bolts best possible. You can check them again once the drive belt is on and under tension.

Slide the drive belt back into place and make sure that it's seated in at the grooves on all of the pulleys that have them. Remember to install the belt using the same path as you took it off. I managed to find one wrong way to get the belt back on that would not have worked, but looked good.

About the belt tensioner….. mine had broke at some point in the cars life and the BMW repair was to use a black plastic tie wrap to hold the two pieces together. I had thought that they had used the tie wrap to compress the spring, but after compressing the spring myself I found that a tie wrap today would not hold the thing together

I waited to put the fan blade on later. With the temperature outside at 17F (-8C) I didn't think that the engine would heat up that fast. I started the car and let the temperature come up a bit, all the while checking the coolant level and opening the bleed screw on the top of the radiator. It may seem a lot more goes in than comes out. If you changed the antifreeze, put the right stuff back in. In my area of driving with the wind chill it can go down to -55F (-48C) in the winter.

No leaks and the engine sounds much better again!

Shut it down and get the rest of the engine bits installed. Spin the fan back on and tighten it a quarter turn. The engine will do the rest.

THE OLD PUMP
So now I think I know why there wasn't a core charge for the new water pump. Usually I would have expected to pay an extra $20 for the new water pump and then get the $20 back after returning the old water pump to the shop.

Photo Details
"GG" -Look I found the drill that I broke off!
"HH" - It looks like you can drill into the water pump at about a 30 degree angle.



That's it... so far it's running great and nothing has fallen off.

Looking forward to reading it.

Did yours fail, if so what were ther sypmstoms?

I take it the jacking screw tabs broke off? I've never seen that before. All of them I've replaced came right out when using the bolts to push the pump out of the block.

what are jacking screw tabs and how do you use them?

They are the holes with arrows pointing to them in Ken's photo. Once you have removed the retaining bolts/nuts (depending on if you have a 4 or 6 cyl), you screw the "extraction bolts" into the jacking tabs on each side, which physically pushes the water pump out of the block. Pretty nice and simple design, actually. BMW water pumps, for all their problems, are exceedingly easy to replace (except apparently not for the OP - that's one nasty photo up top).

wow...just wow...i'm speachless...

i've never seen anything like thi, no,...wait,...i have, but i can't talk about it without wanting to break something...


to the op, welcome to the fest.



df

Mine was similar on my '97 318. It was fused to the block and the jacking tabs broke off immediately. It took extreme violence to get it out.

Hey my serpinetine belt seems to kinda jump half off the altanator pulley
When i start the engine the altanator is new and water pump and pulley and belt.
Is there somthing i need to do and how do i do it.

Check the thread you started about that problem. You only need to post one place. By putting your questions in more than one thread you get answers in more than one place, many of them duplicates. There's no sense in that.

Glad you got it done op, Lola is over 200k now so cooling system may be a winter project for me bell maybe that's what my "super charger" wine is on my car ha ha

Oh and welcome to the fest

can somone explain witch bolt tightens the serpintine belt from the pics above
thanks

it's not a bolt it's a tensioner

L

Ok so how do you tighten the (tensioner)

It tightens itself. If you are having problems with it being loose and/or causing a squealing sound then it will need to be replaced.

Getting ready to replace the water pump on my daughter's '96 328i. Can't remember laughing as hard as when I read T-808's tale of woe. Sounds like you have the same luck that I do. I'm sure the pictures will be extremely helpful. Thanks for the great information and the laugh. I needed it.

Keep in mind that there are slight differences between T-808's engine & water pump and the engine in your 328i.

I'm working on a model of tensioner just like this one!!!! I can't figure out for the life of me how to work it, can anyone help me plz.

Howdy. I know this thread is a little old, but it is the closest thing to anything useful I could find about the water pump on my friend's 318i 91, so I figured I'd augment it for posterity.

I ran into the stuck water pump problem also, and wanted to present you guys with another less messy solution:

After I had all other components out of the way, I started doing the pry screws approach and immediately noticed that the bottom screw was turning way too easily, the voila, bottom bracket broke off. No way I was going to try to force it out from the top screw alone, so after some uneventful wrestling and hammering, I called it a night and revisited it the next day with a fresh mind. Take a look at the pictures, one starting at the water pump, other with a easily maneuvered crowbar.
The pivot point provided by the in and out coolant lines above the water pump is perfect and quite solid. From there I just leaned on the crowbar to put some pull on the water pump, then moderately hammered the pump to one side, then the other. It's kind of like wriggling it out. I didn't have a mallet handy so I used a regular hammer.
You don't have to pry super hard, and you don't have to hammer super hard, just steady pressure and steady hammering.
To see if it was working, I put a bolt through the top pry hole as far in as I could by hand, then pry and tap for awhile, then lo and behold! The screw goes in further by hand now! You have steady measured success and before you know it, the pump will pretty much pop out and dump it's remaining juice all over the place.

Considering that nothing needs to be drilled, purchased or broken to do it, I consider this the best method I've seen yet to get unstuck one of these wonderful pumps.
The next day I found a rubber mallet 20 feet away. SMH.

Now I have to address the stripped water pump bolt that I found (or made). I love aluminum!

Thanks for reading!

Fyi - car has 180k on it, water pump was replaced 50k+ ago.

Sent from my DROID BIONIC using Bimmer App

All,

My dad and I experienced a lot of the same problems when removing the water pump from my 95 318i --- it was practically fused to the engine block which made it near impossible to remove. As a result, we invented this water pump removal tool which worked great. We've sold several of them domestically and most recently even internationally. Here is our website:

http://mysite.verizon.net/res8nm26/bmwtools/index.html

Thanks!
-Lauren

you guys are so funny drilling the pump or pulling it with special tools, you need to be creative, do you see the screw whole in the midle of the 2 wholes where you pulled the screws from.
using the same srews from the pump, put them on the wholes and thinght them up evenly the one up and the one down, and that will lossen up as easy as eating a candy, i hope this helps every one

Originally Posted by betito

you guys are so funny drilling the pump or pulling it with special tools, you need to be creative, do you see the screw whole in the midle of the 2 wholes where you pulled the screws from.
using the same srews from the pump, put them on the wholes and thinght them up evenly the one up and the one down, and that will lossen up as easy as eating a candy, i hope this helps every one

Except for the whole bit about the two pumps above where the jacking tabs you're describing snapped off on them.

So, lets use your idea again, except now you have to do it without the jacking tabs. (Because they just snapped off like I told you).

How easy is it now again?

Before jumping in with a 'smart' (term used loosely in this case) comment read all of the little words. They may have a relevant meaning.

Ed