Replacing water pump gaskets on 2.4

[jonnythan]

I had a small coolant leak for a few months that I planned to fix in the spring. Tonight it turned into "coolant pouring out onto the ground that I have to fix right now."

The coolant appears to be coming from the gasket that separates the water pump body from the water pump cover.

It looks like it might perhaps be possible to get to this gasket without removing the exhaust manifold. Does anyone know if this is in fact possible? If it is, I'm going to try it out tomorrow.

If it's not, I'll probably just buy all the related parts (including a water pump, water pump gasket set, and exhaust manifold gasket), toss them in the back seat, and drive the car down to Midas and ask the guys to install the pump and gaskets. It's just too cold and dark here to spend that much time working on the car outside. I really don't have the money right now but what can ya do.

[jonnythan]

I noticed in another thread someone mentioned a "weep hole" on the water pump body. What is that? Is it possible for that to leak badly, and is the only fix a new water pump?

What would the general shop labor time be to replace a water pump?

[Matt95GT]

This thread might be useful to you...
http://www.gaownersclub.com/forum/showthread.php?t=82845

I think you can get to all the bolts needed to remove the thermostat/inlet housing from the pump itself. You will likely need some socket extensions and swivels to do so, but should be possible. It is the 3rd bolt holding the pump itself to the timing chain housing that is hidden enough to require manifold removal.

As for the pump, keep in mind you have the pump design that requires removal of the timing chain to change. (see my pump comparison in the link above) Labor varies, but I've seen upwards of $400 to change the pump.

The weep hole faces downward and is in the center of the pump at the narrowest point in the shaft. When the pump wears, any gaps/play in the shaft will let coolant around the shaft, the weep hole lets it out instead of being forced into the timing chain housing and mixing with the oil. (although it was bad enough on my 94 to do this anyway and trash the engine) It is possible for it to leak badly... on the "last trip" it pissed out coolant fast enough to require half a dozen refills to get home. Here, it is easiest to see in this pic of my old 94 when it was leaking badly from the weep hole:
http://www.fazeshift.org/pics/albums/userpics/09-15-05/DCP06752.JPG

Now I'm not sure if the 2.4 style pump even as a weep hole, so you may need to inspect yours and compare with the pic. If it has a weep hole, and it is leaking from there, you need to replace the water pump. If the leak is coming from the seam between the water pump and the t-stat/inlet housing, then replace that gasket.

[jonnythan]

It's hard to tell just where it's coming from.

I'll go in tonight and see if I can get that thermostat inlet/impeller housing off, because it really seems that's where it's leaking. It could also possibly be the weep hole (if there is one) or the gasket connecting the inlet housing to the engine block. It really looks from your picture like the exhaust manifold is in the way of a couple of the bolts on that housing, but I'll give it a go tonight.

I looked up job labor and apparently a shop would charge 4-6 hours to do this. I can't afford that, so I'm going to go for it myself.

Hopefully I can get that housing off without taking the exhaust manifold off and replace those two gaskets. If I do have to end up taking the manifold off, I'm just going to go all the way and replace the water pump as well. For such a big job, the $50 for a new pump is basically inconsequential to the time and damage to the engine if it dies.

I really hope I don't have to replace the water pump, but I think I'm capable of it if necessary... though I'm always apprehensive about removing parts I've never had to touch before, such as exhaust manifold or timing chain parts. I much prefer working on stuff I've seen before ;)

My only consolation is that I've had a smallish leak for quite some time, but oil analysis confirms zero coolant in the oil.

[Matt95GT]

If you do end up replacing the water pump yourself, just make sure you have a solid procedure for removing/putting on the timing chain. The tensioner can be especially tricky, as I've seen in several threads.

[jonnythan]

I have the GM service manual for the vehicle. I assume that procedure should be sufficient.

I did skim it last night and don't remember anything about actually removing the timing chain itself. I remember seeing that I need to remove the timing chain *tensioner* which would seem sufficient to me for replacing the pump. I'll have to go check it.

[jonnythan]

No timing chain removal, but must remove the tensioner:

http://i5.photobucket.com/albums/y190/jonnythan/waterpumpremoval.jpg

[Matt95GT]

Oh, can probably just slip it off once tension is removed. Just make sure the tensioner is release properly on re-assembly... even shops seem to mess that up sometimes.

[jonnythan]

I'm reading through the procedure more carefully... and it seems to get the engine cover off, I need to remove the alternator and an engine mount??

[Matt95GT]

I'm reading through the procedure more carefully... and it seems to get the engine cover off, I need to remove the alternator and an engine mount??

Yup... getting in there is not an easy procedure... hence the bitter dislike for the 2.4 water pump design.

[jonnythan]

My buddy Mike had his old Dodge Caravan V6 engine sitting out in the garage.

He showed me the water pump on it.

It's on the serpentine belt. Remove the belt and the water pump comes off with 5 bolts.

That's it.

Why would GM run the water pump off the timing chain??

I'm rethinking biting the bullet and bringing it to Midas.

[jonnythan]

Bad news:

http://i5.photobucket.com/albums/y190/jonnythan/water%20pump/closeup.jpg

http://i5.photobucket.com/albums/y190/jonnythan/water%20pump/closeup2.jpg

That's the gasket between the water pump and the timing chain case, so the water pump has to be taken out.



The good news? My dad called tonight and I mentioned it to him. Told him I was going to spend the weekend removing the engine mount, exhaust manifold, etc.

Then he said "take it to a shop. I'll put it on my card."

edit: Then I told him the estimates and he said "that's too much" ;)

[jonnythan]

OK, back to doing it myself.

Between these gaskets:

Water pump housing to water pump
Water pump housing to engine block
Water pump body to engine
Exhaust manifold
Timing chain cover

Which gaskets do I need to use gasket sealer on, and what kind of sealer should I use?

[sunrunner_pei]

IMO, if you're going that far, you should replace the water pump while you're in there. The pump is only ~$150, much less than the labour it costs to remove/install it. You don't want to do all this work, only to have your 10-year-old pump fail soon after. :(

[jonnythan]

Definitely replacing the water pump as well as the timing chain while I'm in there. Too cheap not to. A new pump with a lifetime warranty is $50 from the local parts stores.

I'm cheap, but I ain't dumb ;)

[sunrunner_pei]

Sorry, didn't mean to sound like I was accusing you of either. Just looking out for a fellow member. I'm glad to hear it! :)

[jonnythan]

No no, I appreciate it :D

Prolly replace the timing chain as well. $37 to replace a 180,000 mile old chain. Might as well.

[Matt95GT]

A new pump with a lifetime warranty is $50 from the local parts stores.


Don't get a parts store pump. This is one item I would insist on brand new genuine AC Delco only. Many people had problems with the 2.3 pump from parts stores that didn't fit, were grinding inside, etc. A lifetime warranty isn't worth much when there's potentially $400+ of labor to swap it. The AC Delco pump I got was only $10-15 more than the parts stores anyway.

For what it's worth, every single mechanical part I've obtained from Autozone, etc failed within 2 years.

[jonnythan]

$49, $124. What's the difference?

No thanks. I'll stick with the parts store pump.

[jonnythan]

OK, it was $586 out the door at the (awesome) mechanic. It just got way too col and nasty to start this big a project out in front of the house.

[matts]

OK, it was $586 out the door at the (awesome) mechanic. It just got way too col and nasty to start this big a project out in front of the house.

ouch!! i'm glad i have a few mechanics in the family. i've had problems with my 2.4 going through gaskets. replaced the water pump once but the gasket like 4 times now. this last time i didnt use a gasket. a friend of mine told me about some pretty bad form-a-gasket stuff. only thing he could find that would hold 6K+ rpm on his race motor.

put it on and *knock on wood* haven't had any problems with it yet.

when the pump was replaced they couldnt get the hydraulic tensioners to work again. had to take it BACK apart and put new ones on.

[Pontiac]

ouch!! i'm glad i have a few mechanics in the family. i've had problems with my 2.4 going through gaskets. replaced the water pump once but the gasket like 4 times now. this last time i didnt use a gasket. a friend of mine told me about some pretty bad form-a-gasket stuff. only thing he could find that would hold 6K+ rpm on his race motor.

put it on and *knock on wood* haven't had any problems with it yet.

when the pump was replaced they couldnt get the hydraulic tensioners to work again. had to take it BACK apart and put new ones on.

That form-a-gasket stuff sounds like pretty cool stuff. Think it'd work in place of the LIM gasket?

[matts]

don't see why not. i can't remember the name of that stuff for the life of me. i can tell you it was expensive. $40 for a small tube of it....a tube like half the size of a tube of toothpaste.

[Pontiac]

It'd be worth it if it made this a close to permanent fix.

[matts]

yeah, that's the same thing i said.

[jbrow1]

Wow, I think I'm not even going to look and the wife can trade the dang thing in.
:mad:

[matts]

Wow, I think I'm not even going to look and the wife can trade the dang thing in.
:mad:

well unless she's trading it in on a brand new one i personally wouldn't bother. as of right now you know your car and what problems it has. get a different used car and you have to start alll over again with fixing things and figuring out what needs to be fixed and what's still good, etc. it can be more of a headache than it's worth IMO :)

[jbrow1]

Exactly all the things I've been thinking about. We bought this car used and I've been very impressed with it. Think it had 115K on it and we've got it up to 164,000 miles now. All I've had to do is put a blower fan in it and a wheel bearing. Just put a new set of shoes on it last friday. I really don't think it's the water pump. But I suppose if it was it might just be worth having a shop fix the thing. Main reason is because I HATE PAYMENTS!!. lol
I've had two new vehicles in my life and I'll probably never buy new again. Unless I hit the lotto of course ;)