: water pump cover leak

02-14-11, 05:33 PM
I got a small leak from the water pump cover gasket (94 STS). I replaced the gasket in the summer. I tightened down the bolts snug but I did not want to strip them. Each one feels tight. When the weather gets a little warmer, I will remove cover and try a new gasket. My other Caddy never leaked from this cover. When I removed that cover, there was no gasket. All it had was some RTV sealant. Do you guys use the gasket or just RTV? That gasket really doesn't fit in that groove so well.

02-14-11, 07:15 PM
Talk to Chris at RippyParts up ^^^ in Vendors. There's a redesign water pump cover/thermostat housing which uses a different silicone seal.

02-14-11, 09:48 PM
Someone tried to save $5. Install the proper seal.

02-16-11, 03:29 PM
that's the seal I installed. do you use any RTV with that gasket?

02-16-11, 06:47 PM

I'll bet you got the new seal for the old cover - different seal groove. Was your original seal black or red ?

02-24-11, 04:38 PM
I can't remember the color. I'm 90% sure it's the cover leaking. How can you tell if the water pump is leaking? If the pump is leaking, where would the antifreeze come out?

02-24-11, 04:52 PM
I can't remember the color. I'm 90% sure it's the cover leaking. How can you tell if the water pump is leaking? If the pump is leaking, where would the antifreeze come out?

You would have to get underneath the car and do some good flashlight searching - the water pump would show a drip directly under the engine side of the water crossover/pump pulley itself.

02-28-11, 04:47 PM
I got under car today and found out it's not the water pump cover leaking. It's actually the water pump. I've never changed the water pump in a northstar before. I realize I have to rent that special tool to remove water pump. Other then that, are there any tips you guys can give to swap out pump? thanks.

02-28-11, 04:47 PM
On the drive/pulley side, the water pump seal could be leaking through the weep hole, or you could also have a leak between the water pump and crossover housing - there is an o-ring there. Or your cover could be leaking on the other side. Or your coolant crossover seals could be leaking, but you better hope not - that's a bear to R and R in the car!

02-28-11, 05:58 PM
from underneath car, I can see antifreeze leaking out from the backside of the water pump. I removed the water pump cover and will be getting new pump and tool tomorrow. At the start of this thread, I mentioned that I thought I had a leak from the cover which I changed in the summer. I just realized I changed the seal in my 95 Eldorado, not this 94 STS. I see that this STS has the original water pump cover. It looks like there was no gasket there, just some RTV. Do you think the Caddy dealer will have the new updated water pump cover in stock? I really can't wait to have a new cover shipped to me.

02-28-11, 06:32 PM
Only way to know is to call their parts dep't. I'll bet you're looking at $60 over the counter. The new cover comes with the thermostat, gasket, seal gasket, water outlet and outlet bolts.

02-28-11, 08:12 PM
Pete - here's a tip - to remove the pump, rotate clockwise. To install, rotate counterclockwise. If removing proves to be difficult, you can use an impact on the special socket but use short, quick blows to avoid cracking anything or breaking the tool.

Clean the O-Ring groove in the crossover using a flat tipped screw driver. Ensure the groove is clean, degreased. A small bead of RTV in the groove will hold the new O-ring in place while you install the pump. When you get the water pump into position, pull it through and hold the pulley so you're putting constant pressure on the o-ring. You can't afford to have that o-ring slip out of place and it's difficult (impossible) to see once the pump is in the crossover.

On the cover, I always use a new gasket, with a bead of RTV on the outside edge of the seal. If the gasket should fail or shrink over time, you still have the RTV there to serve as back-up.

Must my 2 cents.

Good luck my friend.

03-02-11, 06:06 PM
The pump came right out with no problem. I went to my local Caddy dealership and they had the new complete pump cover assembly in stock- $100. Installed everything back together and car runs great again, no more leak at all. With that tool, changing the water pump is a very simple quick job. I probably could complete job in 30 minutes. How's it going Jake? Hope you and the family are adjusting with the big move.