1. We are working on the forum's attachment system. Attachments and avatars will be intermittently affected over the next 24 hours.
    Dismiss Notice

How to replace the water pump

Discussion in 'Article Submissions' started by Matt, Jun 18, 2016.

  1. Matt

    Matt Silver Supporter

    Messages:
    2,540
    Likes Received:
    1,062
    Total time, about an hour. On the OS someone claimed to have done it in 30 minutes, but it took me about an hour from getting everything out to having everything packed away.

    Make sure the engine is COMPLETELY cool before doing this. Best bet is to do it first thing in the morning.

    Remove the radiator cap and upper radiator hose. Make sure you have a catch pan under the truck to collect the antifreeze. You don't need to drain the radiator unless you are doing a flush and fill at the same time.

    There's a variety of methods people use to loosen the fan clutch, but I will say you don't need a special tool. A 2' length of chain, M8 x 1.25 bolt, a quick link and 36mm open end wrench will work.

    Take out one 13mm bolt from the water pump pulley and attach the chain to the pulley using the M8 bolt. Attach the other end of the chain to the engine lift bracket and using a 36mm open end wrench, loosen the fan clutch nut.

    [​IMG]

    [​IMG]

    Once you have it loosened, remove the 10mm bolts from the top of the radiator shroud and the fan electrical connector (just a bit to the right and below the shroud bolt).

    [​IMG]

    Remove the AC lines from the clips on the radiator shroud on the left side. Remove the fan clutch nut from the water pump. You'll be able to move the fan a bit to clear the shaft.

    Pull the radiator shroud and fan assembly out in one piece. You can move the shroud forward on the left side to clear the radiator neck. Be careful not to smack the radiator with the shroud as you'll damage the fins.

    [​IMG]

    Obviously, if you're just replacing your fan clutch, this is where you'd stop and do what you need to replace that...but, that's not what I'm doing here, so, onward. Remove your serpentine belt completely.

    [​IMG]

    You can now undo the remaining 13mm bolts from the pump pulley and remove the pulley itself. You might want to leave the chain attached to the pulley so it doesn't spin when you're trying to undo the bolts. As you can see I didn't and had to reattach it, but now that the fan etc is gone there's a lot of room to work.

    Once you've got the pulley off, remove the 10mm bolts holding the water pump on...make sure you have the catch pan under the water pump to catch the anti freeze.

    [​IMG]

    One dead water pump. You can't see that there's anything wrong with it, but it ate it's bearings.

    [​IMG]

    Installation is the reverse of the removal. Make sure you clean the surface where the water pump sits. The gasket only goes on one way, so if the holes don't line up, flip the gasket around. The water pump bolts only need to be hand tight...89 inch pounds, so don't swing off them. The pulley bolts get torqued to 18 ft pounds.

    New pump installed with the pulley and belt reattached. Reattach the chain so you can get the pulley bolts to the right torque.

    [​IMG]

    Now is a good time to wash down everything with clean water to remove the antifreeze that you spilled...it's no good for paint etc.

    When you're putting the shroud and fan back on, make sure that the pins on the bottom of the shroud go into the locating holes, you'll have to get under the truck to see and align them.

    Be careful when you reattach the fan clutch nut to the shaft, the threads are fine and it's really easy to cross thread them. There is a torque spec for the fan clutch nut, but you're not going to get a torque wrench in there, so go with the German torque setting...gud an tight. Remove the chain and put in the last pulley bolt.

    [​IMG]

    Plug the fan electrical connector back in, put the shroud bolts back and replace the top radiator hose. Top up the radiator with either Dexcool diluted 50/50 or whatever antifreeze you're running and do the normal burping of the system checking for leaks while you're running the truck.

    All said and done, about an hour and it's really quite simple.
     
  2. MRRSM

    MRRSM Gold Supporter

    Messages:
    1,572
    Likes Received:
    706
    @Matt What an Amazingly Clever Idea for a Specialty Tool... and Marvellously Economic set of R&R Procedures and Images! ... And so you've earned Serious Props from anybody that has to do this Job...(Pretty soon now...That will be ME!)

    Thanks for what is...One Perfect "Write-Up".
     
    Redbeard and Matt like this.
  3. seanpooh

    seanpooh Well-Known Member

    Messages:
    419
    Likes Received:
    30
    Good how to guide for everyone. When I did mine, instead of removing the fan shroud, I just cut it with a angle grinder and metal cutting wheel where those arrow and symbols are to wiggle the fan and pump out. Worked well for me.
     
    dkvasnicka, Mooseman and Matt like this.
  4. dkvasnicka

    dkvasnicka Silver Supporter

    Messages:
    340
    Likes Received:
    170
    Yep, the chain method worked well for me too. Also I don't think you need to torque the clutch nut at all -- provided your fan is turning in the opposite direction to the tightening direction. Put a bit of anti-seize (I use a kind of copper paste) in the nut, thread it on and then spin the blade by hand until the nut reaches the end. All the subsequent starts & runs of the engine will do their job and torque it more than you'd need :wink:
     
  5. Mooseman

    Mooseman Moderator

    Messages:
    9,675
    Likes Received:
    4,346
    Great write up! A couple of tips to add:

    - Cut a "slit" in the fan shroud where there radiator hose neck goes so it clears it when sliding the shroud back in. Might also avoid damaging that radiator neck.

    - As mentioned by @dkvasnicka , anti-seize on the fan clutch will help you for later removals. And once it's threaded in right, leave it loose by a couple of threads. When you start the engine, it will self-torque since the pump spins in the required direction.
     
    Blckshdw and MRRSM like this.
  6. Matt

    Matt Silver Supporter

    Messages:
    2,540
    Likes Received:
    1,062
    On the slit, I didn't and was able to finesse the shroud back in, but it's not a bad idea for those that aren't patient.
     
    Redbeard, 02 green tb and MRRSM like this.
  7. dkvasnicka

    dkvasnicka Silver Supporter

    Messages:
    340
    Likes Received:
    170
    I'm glad I'm not the only one who decided to "violate" my truck and cut a slit into the shroud :biggrin: I was just too afraid of the GMT gods to talk about it here :biggrin:
    No, seriously, it really helps a lot when taking the shroud out and lowers the probability of you bending your blade. And as we all know, taking the shroud out is not something you do just once in the course of the ownership on GMT360... :whistle:
     
  8. billzie

    billzie Well-Known Member

    Messages:
    49
    Likes Received:
    5
    Getting ready to do this job. Actually my 02 EXT has what it I think is a bad WP, lots of play, it's a beater and may be sold soon. So, as preventative maintainence, I'm going to do it all right on my 06 EXT DD and swap it's good used parts to the 02. (Actually all started as a Alt RR on 02 and noted bad WP play, so had locally rebuilt Alt done it'll go to 06 as well).
    Anyway, I bought all ACDelco parts from RA (rec'd today). Surprise! ACD WP # 252-822 $35 listed as "professional"is made in CHINA and only comes with a paper gasket. I read in another thread to order ACD metal gasket separately another $12, even Felpro is paper though. Any thoughts on this? All old school engines use paper. Another note, the ACD WP # 251-731 is listed as OEM but is about $84, hope it comes with stock metal gasket lol.
    Also RR tensioner, idler, WP pulley, rad cap, T-stat, temp sensor, U&L rad hoses, belt, and doing drain/flush and fill with new dexcool.
    I am not using the chain method. I already contacted "Toolguy1954" on eBay as recommended by Mayo04 and bought the home made tool to hold the clutch bolts. Only about $14 shipped and I already have the entire lift bracket removed to RR the above mentioned ALTs.
    Great write up and pics! Definitely will help me.
    Billzie
     
    Last edited: Aug 11, 2016
    Matt likes this.
  9. Mooseman

    Mooseman Moderator

    Messages:
    9,675
    Likes Received:
    4,346
    Just because it's "made in China" doesn't automatically mean it's junk. It could have been built to ACDelco's specs and pass their QC. There is not a single brake rotor or drum produced in North America anymore. They're all made in China. But I digress.

    For the gasket, I don't use it. I use RTV. That's what's used between the block and timing chain cover so why not on the WP? I haven't used a gasket on them in over 20 years (exception for imports that use an o-ring).
     
  10. billzie

    billzie Well-Known Member

    Messages:
    49
    Likes Received:
    5
    I agree, not automatically, but usually lol. I worked an auto parts store chain in the Midwest during the initial influx of China made parts. In regards to rotors/drums, we carried a premium line made in the USA (some in Canada) and the cheap line made in China. Almost every Chineese rotor I checked for true on the lathe were out .08" or more - some were potato chips, the N Amer rotors typically under . 01, barely enough to make a clean up pass that would matter. Our machine shop offered free lathe work, all the shops and alley mechanics we supplied would get the cheaper rotors/drums and then have us turn them to true.
     
  11. jsheahawk

    jsheahawk Well-Known Member

    Messages:
    410
    Likes Received:
    109
    Great write-up.
     
    Matt likes this.
  12. smt 59

    smt 59 Well-Known Member

    Messages:
    3,354
    Likes Received:
    1,118
    Mounce likes this.
  13. djthumper

    djthumper Administrator

    Messages:
    13,541
    Likes Received:
    3,165
    Admin Post
    He may have to relink to photobucket.
     
  14. Mooseman

    Mooseman Moderator

    Messages:
    9,675
    Likes Received:
    4,346
    I already PM'd him about it.
     
  15. smt 59

    smt 59 Well-Known Member

    Messages:
    3,354
    Likes Received:
    1,118
    Write up is great, the visual is always a nice addition.
     
  16. Matt

    Matt Silver Supporter

    Messages:
    2,540
    Likes Received:
    1,062
    Somethings up with photobucket. ALL of my pics are no longer there and they were the only copies. I've contacted them and we'll see what happens. If I can get them back, I'll relink them from elsewhere.

    As an aside, why can we just drop photo's straight from a hard drive?
     
  17. Mooseman

    Mooseman Moderator

    Messages:
    9,675
    Likes Received:
    4,346
    The biggest problem is that they have to be reduced before they can be uploaded directly to the forum. I use Windows Image Resizer (an old XP Powertoy that has been ported to Win 7+) and if it's on my phone, I just email it to myself and it reduces it automatically.
     
    Matt likes this.
  18. Wishbone

    Wishbone Gold Supporter

    Messages:
    340
    Likes Received:
    145
    I kinda like the chain idea. I use a ratchet strap (minus the ratchet), duct taped to the water pump pulley, then wrapped several times around and hooked to the engine lifting bracket. waterpumpstrap.JPG
     

Share This Page