testknight

As mentioned I replaced my water pump over the weekend that was damaged to a seized idler pulley. I had the water pump replaced once before but with the charge being around $850 parts/labor I chose to it myself this time. I found a water pump on parts.com for a total of $246 and I will get back $54 of that with my core return and then with $35 on two gallons of premixed coolant from MB I'll have about $225 total into the job.

I am not doing a full write up with pics and all that, but since I found zero guidance on this job anywhere I felt the next guy may benefit from my notes. I'd say this is a medium level job and for someone that is at least somewhat comfortable wrenching on cars. As I did this I also installed the needswings pulley saver kit.

1.) Remove engine cover, and air ducts (if you need guidance on this part, close the hood and just take your car in to a shop)

2.) Remove belt...I also pulled off all needed pulleys for the pulley saver kit (refer to their website on instructions for this kit)

3.) Drain antifreeze...look for big red knob under radiator on the driver’s side of car (for this doc I will refer to this as the right hand side)...just above it is a spout..place a hose in there so the coolant can flow into it and not make a mess.

4.) Remove the cross brace that runs over the radiator (its the black brace that has the hood latches bolted into it) - this will allow the fan to come out...I've read of folks getting it out without doing this, I was not one of them. It is pretty easy, its about 6-8 bolts and since I was unable to disconnect what appeared to be a wire connection on the right hand hood latch, I just un bolted it and moved it out of the way. Unclip the hood release cable as well as the small coolant return line (they both just need pulled off clips so you can get the cross brace out)...then you'll see three plastic tabs holding the plastic air duct opening for the air intake tubes (where the air goes in behind the front grill, just above the radiator, two big holes for the ram air...)...use a flathead to pull those out and you can just unbolt the rest to move it out of the way.

5.) Remove fan - unplug the large wiring connection on the RH side of fan. Depress needed tabs and lift up. I found removing the fan to be a pain in the ****, but you can eventually walk it out and back in again...just note you really need to push on the large coolant hose that connects to the top RH side of the radiator...really push it out of the way to it clears the right hand side of the fan as you walk it out...note the small coolant return lines can get in the way as well and be wary of not damaging them as you pull it out.

6.) Remove water pump pulley. Probably easiest to just use an air tool on this as using wrenches is tricky is it wants to spin the pulley. I managed to get it off using some wrenches holding one bolt as I undid the other with a socket wrench. When I put mine back on I also used wrenches, but this is where an air tool can really help...just be very careful of how much the air tool torques it down. Since I have an over sized crank pulley the water pump pulley comes real close to it, so I was able to use a radiator hose to wedge between the two to assist in holding the water pump pulley in place as I torqued it down (I combined this along with just holding it by one hand as I torqued down with other...the combination of the hose being wedged between the two pulleys and my hand was enough to meet torque specs...8 foot lbs)

7.) remove water pump - probably 10-12 bolts hold this in place and three hoses will need to come off....two head sized, but the bolt lengths are all different. Be very careful to note exactly where each bolt is placed....make a map. Note that the water pump has a lot of holes that would appear to be bolt holes and not used, it’s good to note these on the map as well. Once unbolts use a screw driver to lightly pry it off the block. One of the bolts runs through the alternator (just pull this out, nothing else needs done with alternator other than to put this bolt back on.)

NOTE for oversized crank pulley folks - There is one bolt that will be near impossible to get to...it runs just behind the pulley. The ONLY way I was able to get this out was because I happened to have an 8mm flexible socket I placed on an extension with adapter(I do not see a universal one working here...)...if you have one of these (and I do think you'll need it as you can get a wrench on it, but will not have enough room to turn it)...come in with the extension parallel to the ground...you will not be able to get to it from above or below, but just straight in at an angle to get behind the crank pulley.

Tip - there is a small hose that needs to come off on the far right of the water pump. When you get there you'll see you can't just pull it off while the water pump is still attached. The way to do this is to pull the clamp connected to the water pump as far down as you get, the pull the other clamp as far down as you can so when you go to physically remove the water pump you'll just need to apply some pressure to remove the hose from what it is attached to (non Water pump side). When you go to put this back on, have it the same way (small hose attached, both clamps slid down) so the first thing you'll do is slide the hose back up onto where it needs to go and you can start bolting the pump back on...be mindful not to knock the gasket out of its groove)

4.) Reinstall water pump. I spent some time trying to determine if any gasket sealant (other than the supplied rubber gasket) was needed..as it appeared some was used when I had this replaced back in October...however after quite a bit of searching I decided not to use anything other than the rubber gasket....I did and do recommend that a very small bead be placed in the groove where the gasket goes however as to help hold it in place. Once the bead and gasket was in place I took a lunch break so it had some 'bonding time'

It’s important to note that when you go to put the water pump back on, you really can't see the gasket. Before, when I didn't use the bead of sealant (I used some RTV black I believe), the gasket came out easily as I tried working the water pump back in. Just be careful that the gasket stays seated as you press the water pump into place. Crank the smaller bolts to 8 foot lbs and the larger ones to about 18 foot lbs and you're good to go...the alternator bolt needs 30 ft lbs.

The rest you can follow by going backwards.

testknight

I should also add that there are a couple bolts on the brace (the one over the raditor to be removed early one) down below that needs to come out and you'll need ot unbolt the steering oil cooler (I believe thats what it is...looks like a little midget intercooler) and the horn (two plastic round things) as well.

gt4awd

Thanks for the write up. Question, is it required to remove the radiator fan due to space limitations, or can you work around that?

testknight

I'd highly reccommend taking the fan out...but it may be possible. It only takes 30 mins to get out and it'll make the rest of the job a lot easier. Most imprtantly, it gives you more room to work with as you put it back in as it gets a bit ackward when you're working the pump back into place, all while trying to slide in the end coolant hose (short one of far right) and while also trying not to disturb the gasket.

If someone were to try it without (again I advise against)...if you have a larger crank pulley start with the one water pump bolt way down at the bottom by the largest downward pointing hose port...its just to the right of the opening. That bolt may not be accessible with the fan still on (and also note you'll just want to buy a 8mm flex socket to get on it).

W203Ramos

awesome write up. thank you!!! had pulley # 4 fail and ate a chunk of aluminum......i guess i have to order a water pump now.

brauhaus313

This job really sucks.