Changed water pump, now oil leak
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Joined: Mar 2007
Posts: 362
From: Bend, OR
Changed water pump, now oil leak
I changed my water pump for the first time on my own and was pretty proud of myself. It's the 5th water pump for this car in it's 19 year life. I bought a new unit from O'Reilly's with a lifetime warranty and am very pleased with its performance so far. I have driven 750 miles since I installed it and the car is cold as ice.
There are no coolant leaks but about 2 days after I installed the pump, an oil leak appeared. I had only done around-town driving up to that point. On the third day, I drove 320 miles and lost 1/4 quart. This week I just drove another 430 miles and lost another 3/4 quart.
When I took the old pump off, the drive seal was totally dry. Even now I can see the top of the opti and it isn't covered with oil or anything, it's just got droplets on it as does the whole front drivers side of the engine. Checked underneath on day 2 and didn't see any obvious leak but I'll check again now that it seems to have picked up the pace. Did I miss a step when I installed the new water pump?
There are no coolant leaks but about 2 days after I installed the pump, an oil leak appeared. I had only done around-town driving up to that point. On the third day, I drove 320 miles and lost 1/4 quart. This week I just drove another 430 miles and lost another 3/4 quart.
When I took the old pump off, the drive seal was totally dry. Even now I can see the top of the opti and it isn't covered with oil or anything, it's just got droplets on it as does the whole front drivers side of the engine. Checked underneath on day 2 and didn't see any obvious leak but I'll check again now that it seems to have picked up the pace. Did I miss a step when I installed the new water pump?
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Joined: Dec 2010
Posts: 875
From: Pennsylvania
There its nothing that should have been disturbed when you changed it. Could just be a bad seal or gasket somewhere. My guess would be the oil pan gasket where that and the timing cover meet.
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Joined: Jan 2006
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From: Long Island N.Y. Via Powhatan VA
Re: Changed water pump, now oil leak
If the water pump drive coupler came off when you removed the old pump, (the splined coupler that drives the pump) odds are the oil seal was damaged upon reinsertion. Grab a new pair of WP gaskets, a new timing cover seal for the coupler. Not hard to replace, but easy to damage if care isn't taken on the re-install, even if new, but especially when old. Do a search on the proper install procedure, (search timing cover seal replacement) it's an easy fix with the cover still on the motor once the WP is back out of the way 
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Joined: May 2012
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From: idaho
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Joined: May 2012
Posts: 660
From: idaho
thats a good link for the seal and all that and has good pictures and even some part #. Did you have and or inspect the o rings for the pump drive shaft. Not sure if that would cause that much leakage but I could also see them missing or damaged in repair.
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Joined: Nov 2000
Posts: 1,937
From: Ft. Worth, TX
Re: Changed water pump, now oil leak
I've had the great opportunity of changing the water pump several times in my 15 years of owning the '95, twice it has sprung a leak at the water pump shaft afterwards....I guess it's just when the seal gets a little brittle after time and the shaft gets disturbed a little installing the pump it makes it leak.
As mentioned, be sure to install the 2 o-rings on the shaft that the coupler goes over, this helps isolate vibration on the shaft and lessen the chance of leaks also. And yes, getting the shaft cover seal on is a real pita, when you buy 1 seal, you midas well buy a couple in case you mess one up, you can order these separate.
In fact, I changed the opti in Dec, and it sprung a leak on me, replaced the seal and it still leaks...car has sat now since Jan, put it up for sale and went a bought a new car....If I keep it, the gear will be removed and an electric pump and warning light installed and never have to worry about this poor design again..then I just have the opti to contend with...
As mentioned, be sure to install the 2 o-rings on the shaft that the coupler goes over, this helps isolate vibration on the shaft and lessen the chance of leaks also. And yes, getting the shaft cover seal on is a real pita, when you buy 1 seal, you midas well buy a couple in case you mess one up, you can order these separate.
In fact, I changed the opti in Dec, and it sprung a leak on me, replaced the seal and it still leaks...car has sat now since Jan, put it up for sale and went a bought a new car....If I keep it, the gear will be removed and an electric pump and warning light installed and never have to worry about this poor design again..then I just have the opti to contend with...
Thread Starter
Registered User
Joined: Mar 2007
Posts: 362
From: Bend, OR
Re: Changed water pump, now oil leak
If I remember correctly, water pump drive on the timing cover side did not have an o-ring. The water pump did though.
Do you know or does anyone else know where to buy o-rings and the oil seal?
Do you know or does anyone else know where to buy o-rings and the oil seal?
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From: Long Island, NY
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From: Little Rock, AR
Re: Changed water pump, now oil leak
Last edited by shoebox; May 22, 2013 at 01:33 PM.
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Joined: May 2012
Posts: 660
From: idaho
dealers are pretty quick to get parts in given they dont have in stock. I dont have the answer but given the importance of a good seal in that area I would opt to get the dealer part.
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Joined: Nov 2000
Posts: 1,937
From: Ft. Worth, TX
Re: Changed water pump, now oil leak
If you are referring to the o-ring that slips on the gear shaft and the water pump shaft to isolate noise/vibration from the coupler, any generic o-ring will work, just make sure it is big enough to make the coupler snug on both shaft ends, its just acting as a isolator, not actually a seal.