Leaking water pump, why?

I have a '95 Eagle Vision with the 3.5L V6. Now that winter is approaching and it is getting cooler, the water pump has developed a slight leak, about

5 drops per night. Questions: 1. Why doesn't it leak in the summer? Perhaps a seal shrinks when cold? Is this common? 2. I know that to replace the pump is a major pain and I'll need to do the timing belt at the same time. What will happen if I continue to procrastinate? The pump was replaced at about 35K miles and the car now has just 70K miles on it. Seems it ought to last longer than 35K miles????
Reply to
Bill D
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...because the seal wasn't worn out last summer. It is now. The leak will not cease when the weather warms up. The connection you're making ("Now that winter is approaching and it is getting cooler...") is not real.

The pump, rather than you, will get to decide the time and place of replacement. Its choice will almost certainly be less convenient and more costly than your choice would be.

You're right, it should. In this case, it didn't. Are you certain you got the new-design components?

Reply to
Daniel J. Stern

Reply to
maxpower

In all deference to D.S. and maxpower's collective commentary.........

I replaced a water pump on my wife's 1984 240 GL Volvo with a Volvo water pump (from the local dealer). It "went" the following year at less than 15,000 km. The dealer was as surprised as I was. They gave me another one at no charge. The one they gave me has lasted over 10 years and about 100,000 km.

Just like there is no accounting for taste, there is no accounting for "reliability". If there was reliability, no one in North america (Canada and the USA) would die before 70 years of age, and by 80 years of age we'd all die. It issntso izzit?

Ken Canada

maxpower wrote:

Reply to
Ken Pisichko

Reply to
maxpower

Probably.

fairly.

  1. I know that to replace the

Actually, its very simple on that car. Nice removable cover panels, minimal accessories in the way. All in all, replacing a water pump doesn't get much easier unless you drive a car with an old Chrysler 383 or 440 engine.

Worst case- the bearing seizes, tears up the timing belt, and the car stalls. Its a non-interference engine so it won't trash the valves, but it could strand you unexpectedly. Its also quite likely that it is not the water pump leaking at all, but rather the O-rings where the timing cover housing attaches to the front face of the engine block. In that case, the leak will just keep growing (slowly) and you'll have to keep the reservoir full if you don't want to burn up the engine.

Aftermarket water pumps for that car are notoriously spotty in quality. Stick to a quality auto parts store (NAPA, CarQuest) and get the top-line water pump and not the "economy" line.

Reply to
Steve

Bill,

I've read all the other responses you've received and can relate to your antifreeze leak problem during cold weather. I am posting this additional response since I did not see my experience covered by anyone else's replies.

I had exactly the same experience with my 3.5L 1996 Eagle Vision. I replaced the first water pump at about 22K miles, but about a year after the three year warranty expired. The symptom was that it dripped just a few small drops on the garage floor occasionally after I had it out. I replaced the water pump and the timing belt at the same time (as long as I was in there) and this fixed my problem. (I was told at the time there was a problem with the early water pump design, but the replacement pumps were improved and should last a lot longer.)

It was fine for about 4 or so more years and at about 60K miles, it started leaking again, but only during the late fall and early spring (in colder weather). Since the water pump fixed it previously, I bought another pump and belt (and also purchased a new tensioner, idler and all new rubber hoses since these were all due for maintenance) and went at it again. When I put everything back together, I found that I still had the exact same leak!

I subsequently took off the timing belt cover and ran the engine up to temperature to see where the leak was coming from. I discovered that it was coming from between the alloy housing that was located between the cast iron block and the water pump. I then disassembled everything again (I got very good at it) and when I took off this front water pump housing (it requires removal of the passenger side cam sprocket) I found significant corrosion of the back side of the housing around where the large rubber O-ring (identical to the one used for the water pump) is located. I believe this was caused by use of the dissimilar metals in the design with the antifreeze acting as an electrolyte.

I used a good stiff wire brush attachment on my drill press to clean this all up very well and then put a very fine layer of blue gasket former RTV on both surfaces before reinstalling with new O-rings (there are three of them, one large, two small). I cleaned and retorqued all the bolts to their proper settings and then reinstalled the water pump. When I put everything back together it did not leak and has been fine for about two years now. I'm hoping the RTV will seal the small corrosion pits and help prevent the dissimilar metals from coming into contact.

Since I know of at least one neighbor who had this exact same leak develop on this engine, I strongly encourage you to remove the housing and make sure these O-rings get replaced at the same time that you do the water pump.

Good luck!

Bob

Reply to
Bob Shuman

Reply to
Ken Pisichko

OP was inquiring about pump on a '95 Eagle Vision w/3.5L. Read the previous posts.

Ken Pisichko wrote:

Reply to
Mike Behnke

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