Leaking water pump, why?

Bill D wrote:

> 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?

Probably.
> Is this common?

fairly.

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.

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.

> What will happen if I continue to procrastinate?

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.


> 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????

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.

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

"Bill D" > wrote in message
...
> 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????
>
>

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

"Bill D" > wrote in message
...
> 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????
>
>

Chrysler has what to do with designing Volvo pumps?

maxpower wrote:

> The water pumps on that yr vehicle leaked alot, Due to from what i was told,
> the pumps were not thick enough and they were warping and causing leaks, an
> updated water pump gasket came out and that did not eliminate the problem so
> chrysler updated the pump and used more metal to prevent it from
> warping..where do you thnk all the old(bad) parts went to??? the after
> market rebuilders., and then back out onto the vehicles, thats why i asked
> if it was an OEM part....
> "Ken Pisichko" > wrote in message
> ...
> > 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 ... snip.

Chrysler has what to do with designing Volvo pumps?

maxpower wrote:

> The water pumps on that yr vehicle leaked alot, Due to from what i was told,
> the pumps were not thick enough and they were warping and causing leaks, an
> updated water pump gasket came out and that did not eliminate the problem so
> chrysler updated the pump and used more metal to prevent it from
> warping..where do you thnk all the old(bad) parts went to??? the after
> market rebuilders., and then back out onto the vehicles, thats why i asked
> if it was an OEM part....
> "Ken Pisichko" > wrote in message
> ...
> > 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 ... snip.

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


Ken Pisichko wrote:
> Chrysler has what to do with designing Volvo pumps?
>
> maxpower wrote:
>
>
>>The water pumps on that yr vehicle leaked alot, Due to from what i was told,
>>the pumps were not thick enough and they were warping and causing leaks, an
>>updated water pump gasket came out and that did not eliminate the problem so
>>chrysler updated the pump and used more metal to prevent it from
>>warping..where do you thnk all the old(bad) parts went to??? the after
>>market rebuilders., and then back out onto the vehicles, thats why i asked
>>if it was an OEM part....
>>"Ken Pisichko" > wrote in message
...
>>
>>>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 ... snip.
>
>

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


Ken Pisichko wrote:
> Chrysler has what to do with designing Volvo pumps?
>
> maxpower wrote:
>
>
>>The water pumps on that yr vehicle leaked alot, Due to from what i was told,
>>the pumps were not thick enough and they were warping and causing leaks, an
>>updated water pump gasket came out and that did not eliminate the problem so
>>chrysler updated the pump and used more metal to prevent it from
>>warping..where do you thnk all the old(bad) parts went to??? the after
>>market rebuilders., and then back out onto the vehicles, thats why i asked
>>if it was an OEM part....
>>"Ken Pisichko" > wrote in message
...
>>
>>>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 ... snip.
>
>