Would replacing gasket on 2 year old water pump...

[xHeart]

I am just curious when you removed the 2-yr-old HEPU WP, what was the cause of the leak, is it leaking through the freeze plug area?

There wasn't any visible sign of sorts that would point to the leaking. No movement at shaft, or wear.
The dripping would increase when poked the freeze plug area with my finger.
I couldn't sort if it was dripping when the water pump was running.
I still have it, do you want me to look at something closely, I would?

What is freeze plug's purpose?

The freeze plug purpose is similar to engine freeze plug, if the antifreeze does not have the correct ratio, and if you are in in very COLD climate such as North Dakota in January (-40F with winds etc.), the freeze plugs pop out to prevent damage to the engine block.

My guess is: The freeze plug in your HEPU WP pump was not installed properly at factory (the freeze plugs are usually press-fit, i.e., pressed in with force with some Loctite compound at factory).

Cold you post some pics of the HEPU WP?

Another test is to:
- dry it well
- place the Hepu WP flat on a piece of cardboard with the impeller facing up.
Support with some wood to keep it flat.
- now pour small amount of water (or coolant), maybe 1/2-1" deep, making sure it does not overflow and mess up the experiment!
- periodically check underneath to see if it leaks.

I would post some pictures.
Meanwhile, would you suggest that i increase the antifreeze:distilled water content to a 60:40 ratio or closer, where it lowers the risk of distilled water freezing in severe weather of Great Lakes.

[xHeart]

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[cn90]

xHeart,

Thanks for the pictures.

Did you figure out where the leak came from? Gasket vs Weep Hole?
Did you do the experiment to see if the leak comes from the inner seal?

For some reasons, Volvo engineers designed the WP's weep hole to be at 1 o'clock position (instead of the usual 6 o'clock position in many cars). With the weep hole at 1 o'clock position, coolant will have to fill the bearing chamber, then spill out the weep hole.

I took some random photos from the internet to show you the location of weep hole:

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[xHeart]

xHeart,

Thanks for the pictures.

Did you figure out where the leak came from? Gasket vs Weep Hole?
Did you do the experiment to see if the leak comes from the inner seal?

For some reasons, Volvo engineers designed the WP's weep hole to be at 1 o'clock position (instead of the usual 6 o'clock position in many cars). With the weep hole at 1 o'clock position, coolant will have to fill the bearing chamber, then spill out the weep hole.

Yes, I noticed the hole. I will experiment and look for the cause this weekend using old and leftover green anti-freeze.
Could it be repaired/reconditioned? I like restoring things.

[cn90]

If the leak is truly from the inner seal, no cannot repair it, unless you are very skilled:
- removing the impeller from the shaft is very difficult (requiring special pulley).
- then you need the proper seal.

IMHO, not worth to rebuild the WP.

I am just curious as to the cause of your leak.

[ONV70XC]

...it is difficult to size up looking from the above. Would removing the passenger side wheel help?

Remove the passenger side wheel and bend a plastic shield to reveal crankshaft and all other timing components.

Often as NOT described in owner's manual the water pump will fail appart from any other timing components and often it's NOT necessary to dress another timing belt with all applied idle pooley and tensioner as you may hear advised from professional repair shops or dealer service facilities as their intention is to sell you parts that have mark-ups >50% and "save" labor expenses.

What I would personally do knowing that the rest of my timing components OK and only water pump is pain:

1. unclamp and move out of the way expansion and power-steering reservoirs
2. remove top and front covers off the timing belt housing
3. secure with clamps timing belt onto cam pooleys so that belt teeth stay secured (prefer to use zip-ties for that event). as long as teeth won't slide off the cam pooleys there will be no mis-alighment issues. for extra security you can draw marks on pooleys touching the belt as well to make sure thay match after you finish job. as long as crank-timing housing there, the belt's teeth won't slide off crank pooley as well.
4. unscrew all bolts from water pump as they're accessible without taking off the front wheel. you might want to use penatrating oil carefully squirted locally to each of bolts.
5. release tensioner and remove the water pump carefully sliding past timing belt.
6. if for some reason you see plastic impeller, dump that water pump and get one with bronze to replace.

Never found a necessity to remove the wheel for visibility only if had to replace timing belt and components.

[xHeart]

If the leak is truly from the inner seal, no cannot repair it, unless you are very skilled:
- removing the impeller from the shaft is very difficult (requiring special pulley).
- then you need the proper seal.

IMHO, not worth to rebuild the WP.

I am just curious as to the cause of your leak.

The reason for freeze plug made sense cn90. However, what would be a functional design argument for the weep hole?

[louty]

sorry guys, for me I dont get it, if you question the pump, trash it
it it leaking out that freeze plug, than it was defective
why take all the time to pull it and test it
yes a hun bucks is a hun bucks, but for me........like I said.....trash it........its too critical of a part to play games with

[cn90]

Louty,

I asked xHeart to do the experiment to "satisfy my own curiosity". This is because HEPU is known to last some 100K+ w/o issues. In XHeart's case, it leaked after 2 years.
I was surprised to see the leak from HEPU, thus the question for the "fun experiment" just for the curiosity.
Once the experiment is done, the pump can go in the trash.

[BEJinFbk]

Meanwhile, would you suggest that i increase the antifreeze:distilled water content to a 60:40 ratio or closer, where it lowers the risk of distilled water freezing in severe weather of Great Lakes.

Stick with 50/50 - You'll be fine .