: Water Pump Replacement

02-28-05, 05:25 AM
Hi all,

I'm so happy to have a 'normal' problem with this car (I'm not happy to have a problem, but at least it's not some freaky electrical thing). I've asked some bizarre questions in the past few months while restoring my car, but this one should be easy.

So the water pump is leaking, which I understand is a pretty common problem. I know you need a special tool. Where can I rent (preferably) or buy said tool? Other than that, the job doesn't look too bad.


02-28-05, 07:58 AM
The administrator of the caddyinfo.com board has a water pump tool for rent. You can click on his email from this page....


02-28-05, 08:39 AM
The administrator of the caddyinfo.com board has a water pump tool for rent. You can click on his email from this page....


I'll check that out - thanks.

What's the consensus on the new pump? The stealer is $340, GMPARTSDIRECT is $170 plus shipping (figure ~$200 total). Autozone is $46 or $65 depending on the brand. I've convinced myself that GM parts are generally better quality and thus garner a premium, but at 5-times the price of aftermarket I wonder if it's worth it?


02-28-05, 09:00 AM
I have not had to buy a pump but my approach to aftermarket makers is cautious. You know the OEM part has been designed and tested to do the job; who does the testing on the aftermarket parts? You do.

Alternators would be the most common example of aftermarket pieces that are simply not built or rebuilt to OEM specifications. Brake rotors a close second.

02-28-05, 11:16 AM
Several of the auto parts stores around here have the tool available to borrow for a small deposit. Pep Boys and AutoZone both have it here and they want a $20 fully refundable deposit. Or you can do what Ranger did and make your own...

02-28-05, 11:26 AM
I bought a rebuilt pump, and the tangs that lock into the lugs on the housing were messed up. I ended up breaking several of the lugs on the waterpump crossover housing of my old '94 Concours. It ended up costing $700 for a new pump and crossover! So I will never use a rebuilt Northstar pump!
The pump wrenches are on eBay, there's some made by Lisle (sp?). They are around $20-$30.

02-28-05, 02:13 PM
I purchased a water pump for a 1996 Deville - 58$ at NAPA. It was the "better" aftermarket pump available. Borrowed the socket from a friend. The old pump impeller\bushing was in good shape the leak was occuring at the pump housing o-ring seal. Still pumping 3000 mi later with fingers crossed.

02-28-05, 02:33 PM
Rock Auto www.rockauto.com has the AC Delco pump kit (part number 252-707) listed for $61 plus shipping, tax, etc. I think I paid about $60 for some aftermarket brand from AutoZone two years ago. I'd much rather have the AC Delco part in there.

02-28-05, 02:55 PM
Thanks all. At GM rates I'd have to replace an aftermarket pump 4 times before I broke even on the cost differential. What are the chances of that?

I'm going to go with the $60-something part at Autozone and borrow the tool from them.

Thanks again!


02-28-05, 03:11 PM
True, but with the cost of spilled coolant, tablets, and labor it's not that much more for a better part!

02-28-05, 05:40 PM
Before you replace the pump, are you sure it is the pump that is leaking and not the $9 front cover gasket that is notorious for leaks and has even been redisigned?

02-28-05, 06:29 PM
Before you replace the pump, are you sure it is the pump that is leaking and not the $9 front cover gasket that is notorious for leaks and has even been redisigned?

I haven't really looked real hard at it. It's leaking from that area, just ASSumed it was the pump. I'll take a closer look if it ever stops snowing.

Maybe in the spring....


02-28-05, 09:19 PM
Aww crap....mine is leaking too....from the "vicinity" of the water pump...but I can only guess that this is what it is....I'm starting to lose more coolant than I was last year when I bought the car. From looking at it from under the car....it looks like it will be a royal pain in the **s to work on it at all.:devil:

02-28-05, 09:42 PM
It is most common for the thermometer housing seal to leak. Before springing for a new water pump, but a housing gasket, and see if it solves the problem. The gaskat is less than $10.00, and it is a known problem area. Installation is rather simple also.


03-01-05, 02:36 AM
I just finished doing the water pump a couple of weeks ago...

This is a very neat design - and probably the easist pump you'll ever replace. I'd do ALL the hoses if your up around 80K, they'll need to be done. Heater hoses and return lines - find 'em all.

The leak is coming from the gasket and seal - the pump really won't leak like the old water pumps you're more familiar with... in fact, in most cases you could just reuse the pump, but it is so cheap you might as well do it while you're there! After-market pumps will work just fine - once it is out of the car you'll see what I mean...

Remember - this will turn in counter-clockwise. to loosen it turn clockwise with the "special" tool. It's not a left hand thread, it is a cam effect over center and "tightens" with the movement of the pulley. Oh, yeah, change the belt, too!

The gasket won't fit too well, it is a strange design... you'll "crush" it in position... make sure you clean the area for the seal as well, it will be a mess and probably have some silicone around it. Be VERY sure to get the front seal in place before you tighten the pump - you get one chance to get it right! Your "special" tool will do a perfect job!!!

There will be a return line that connects to the thermostat housing - loosen this back behind the EGR and pull the whole thing attached to the housing forward - I found this the best solution to get this assembly out of the car - you'll want to replace the two 3/4 hoses that link this return anyway.

Be careful not to over torque the thermostat housing bolts - it doesn't take much to "crush" the gasket into place...

The belt tentioner comes off by way of two studs that the cover bolts to... you'll see as you get there.

If you take your time it will be a 4 to 5 hour job with all the hoses being done, as well. Pump, gasket (doesn't come with pump) seal (comes with pump) hoses, belt, clamps - get rid of those damn OEM ones (!!!) antifreeze and pellets should come to around $200.00 or so.

The quote to do all this work via the dealer was $1308.00 parts and labor - 5 hours later I banked $1100 bucks...

Much success!

03-01-05, 05:35 AM
Thanks for the writeup 1996Deville. I'm going to try the gasket first, if that's not it I'll do the pump. The car has 46k miles on it so I'm not going to sweat the hoses right now. I had the heater hoses off when I swapped out the HVAC module and they're fine.


05-27-05, 08:36 PM
Thought I'd resurrect this thread with the diagnosis: the leak is just the seal on the thermostat housing. I put a cooling system pressure tester on it today and pumped it up to 19 PSI (engine cold of course) and waited. Within a few minutes the pressure began to drop and coolant began to pool on that neck by the thermostat. When the engine is hot it evaporates almost immediately so it wasn't obvious that it was leaking there.

So should I replace the pump while I have that housing off anyway?


05-27-05, 09:14 PM
Before you go ahead and replace the pum, put some pellets in the system. You may not think it'll be enough, but my leak went from a mess of coolant around the pump to bone dry. It's very cheap, I think I paid only 50 bucks, definitely better then 500 to replace the pump.

06-21-05, 01:01 AM
my water pump is leaking and i dont know how to change it myself even if i had the special tool. does anyone know what the cost of labor would be to replace the water pump?

06-21-05, 03:48 PM
I just saw another post that said $500 which I think is a ripoff due to the fact that it is so easy.

06-21-05, 04:35 PM
I just saw another post that said $500 which I think is a ripoff due to the fact that it is so easy.

$500 seems to be the minimum price of taking a car to the stealer these days. Seems like even the smallest job is $500.

'don't know how' isn't a good excuse. There's plenty of information here to help you through it. If you've never worked on a car before - try it. You might like it. You save a lot of money and may get some satisfaction out of doing it yourself.


09-20-07, 11:14 PM
Autozone auto parts will loan you one.

09-20-07, 11:15 PM
autozone will loan you one.

09-20-07, 11:17 PM
This thread is 2 years old! I think he has it fixed by now.

09-20-07, 11:22 PM

11-05-07, 12:40 PM
Just stopped by the Caddy dealer and asked for a labor quote to do a H20 pump and they said ~$162 for labor only, its a 2.5hr/pay job.

03-28-08, 06:50 PM
I'm getting ready to do the water pump as it is leaking around the gasket and with over 100k im just going to replace everything while I'm in there.

Ive got the pump with seal (89017900), water pump case gasket (12600020), and a new case to accomodate the new case gasket design (12600022). I'm also doing the thermostat (12559807) and the thermostat gasket (12574478). The thermostat housing i was told should be fine to re-use.

My question is, and its not an easy one... What are all of the hoses that should be replaced? Preferrably with part numbers.... I noticed someone earlier in this thread said it is a good idea to do all the hoses while I was doing the pump. But I am not sure how many there are, and how to identify them. The dealer wasn't much help as they don't have one list of these hoses and didn't want to take the time to look into it. Some help in this area would be greatly appreciated.

Thanks again.

03-28-08, 08:22 PM
George - I definitely recommend you change the short (3" long?) hoses on the driver's side. I think there are 3 - one connects to the water pump. These hoses from the factory are silicone. I replaced one with regular heater hose (3/4" I think) and it lasted 3+ years with no problem, until I did my HG project, and then I replaced all 3, again with regular heater hose. I guess you should use the silicone hoses, but I got all my stuff for the HG project from Rock Auto, and they don't sell the short silicone hoses individually - you have to buy 25 at a time - so I just used heater hose.

The other 5 major hoses are upper radiator, lower radiator, two heater hoses, and the reservoir to tee hose. There are also 3 small diameter hoses - one goes to the coolant reservoir and the other 2 go to and from the throttle body. The latter 2 are molded and I replaced them with the molded hoses. The small hose that goes to the reservoir is pretty straight and I used 3/8" or 5/16" fuel line (can't remember which right now), but I suppose there is a proper hose for that also.

03-29-08, 11:19 AM
At least one of those hoses is green silicone. The reason for that is that the silicone hose will last much longer and due to the fact that is is very hard to get at, I would strongly recommend you use the silicone. Personally, if it ain't broke, I wouldn't fix it due to the difficulty.

12-27-08, 10:33 PM
I am in the process of installing the new pump and was wondering how you know when the pump is tightened counterclockwise enough. Is there a detent or anything to signal it is tight enuff?

12-28-08, 04:56 AM
the pump isnt threaded it is held in place by for lack of a better term small arms, you turn the pump with the socket and it slides into place you cant go any further or "tighter"...

12-28-08, 11:44 AM
Thank you Northstar for the reply.
Yes, I saw the "arms" that lock into the housing but was concerned that the arms could possibly back off during use. I thought there might be an indentation of sorts to prevent this "backing off". I guess I am just used to the bolts, gaskets and permatex way of installing water pumps.
Thanks again for your help.