How Bad is Using Tap Water Rather Than Antifreeze?

My wife’s 2016 Ford Explorer (3.5L V6 w/ 78,000 miles) is losing coolant through its water pump weep hole.

She took it to Ford the other day and the mechanic said he was booked solid for weeks and showed her how to fill the reservoir to keep the car running in the interim.

He filled the reservoir by just grabbing a drop-down hose line and having at it.

I can’t imagine there’s anything other than tap water in the line (could I be wrong) and besides reducing the glycol ratio, we’ve now got whatever minerals that are in the water system introduced into the coolant system.

Am I being too fussy or did she witness really sketchy methods?

No big deal, tap water is pretty clean. You’ll be fine in the short term as long as you aren’t experiencing either freezing or super hot weather.

I dunno. I use distilled water these days because it's cheap and easy enough to get. But I used water from the garden hose for many years in many cars without an issue.

Side note: Is there really nowhere else you can take it if the dealer is booked that far ahead?

I would think that since the water pump service probably includes at least a drain and refill and probably a flush, there wouldn't be any harm done for the couple weeks it'll take to get it in and have the work done.

Are those the engines that dump the coolant back into the engine when the water pump fails, thus wiping the bearings and nuking the engine? If so, I'd park the car or find another mechanic ASAP. The water pump is already showing signs of failure, I wouldn't push it.

slefain said:

Are those the engines that dump the coolant back into the engine when the water pump fails, thus wiping the bearings and nuking the engine? If so, I'd park the car or find another mechanic ASAP. The water pump is already showing signs of failure, I wouldn't push it.

Yes!!! That's exactly what I was coming to post. If you see it coming out of the weep hole, it's filling up the front cover. If you drive it, you'll need an engine. Not sure how a Ford mechanic gave you that advice.

Distilled water is recommended, but tap will be fine, especially as a short term fix. 

I was wondering about that also.  I looked up this repair, and it does involve taking the entire front cover off (the water pump appears to be driven by the timing chains!?!?).  The pump appears to be completely under the cover, so yes, I would think any leaking would go into the front cover area.

Seems like a SUPER STUPID design to me.  Especially since this engine replaces a rather nice (and rather easy to work on) straight six.

Tom_Spangler said:

Side note: Is there really nowhere else you can take it if the dealer is booked that far ahead?

We’re going with an independent mechanic.

Ford told her they’d need the car for a month (no typo, one month) and it would be at least $3,200.

The job is pretty complex (remove intake, valve covers, some other cover that tends to break, and two timing chains) but the internet sez’ 12 to 14 hours (does anybody have access to Ford’s internal hour estimate for the job).

If 14 hours is accurate, even at $150 per hour shop rate, you’ve got $2,100 in labor and what, $300 for the water pump, coolant, and some fancy grease so $2,400 all up.

BTW, the fuel gauge on our last Explorer tended to stick and a Ford mechanic told her it was because she was going to different gas stations causing the system to get confused. I’m not kidding…she felt really patronized and insulted so the trust is lost and she’s happy to take her business elsewhere.

Saron81 said:

slefain said:

Are those the engines that dump the coolant back into the engine when the water pump fails, thus wiping the bearings and nuking the engine? If so, I'd park the car or find another mechanic ASAP. The water pump is already showing signs of failure, I wouldn't push it.

Yes!!! That's exactly what I was coming to post. If you see it coming out of the weep hole, it's filling up the front cover. If you drive it, you'll need an engine. Not sure how a Ford mechanic gave you that advice.

Distilled water is recommended, but tap will be fine, especially as a short term fix. 

 

My understanding is that the weep hole is located between two concentric rows of seals.

If this is the case, we’ve got one row of seals left preventing coolant from mixing with the oil unless the leak is coming from the pump bearing itself in which case, we’re in trouble.

I’ve been inspecting the oil each night and it doesn’t look contaminated.

Thank you all for making sure I was aware of the danger.

Ford pays 8 hours to do it under warranty. 
Figure 1.5x that for cash.

aircooled said:

I was wondering about that also.  I looked up this repair, and it does involve taking the entire front cover off (the water pump appears to be driven by the timing chains!?!?).  The pump appears to be completely under the cover, so yes, I would think any leaking would go into the front cover area.

Seems like a SUPER STUPID design to me.  Especially since this engine replaces a rather nice (and rather easy to work on) straight six.

I've written off owning a slew of vehicles with this engine just because of this one repair.

Does it get below freezing where you are?

914Driver said:

Does it get below freezing where you are?

No, I’m in Southern California, thanks for the concern.

How are the water pump seals holding up on your 914…about as good as the valves are on my RX-7?

GM service manuals say to use "clean, drinkable water"

chaparral said:

GM service manuals say to use "clean, drinkable water"

Whiskey it is then!

I just made a Mazda CX9 owner very sad with my water pump estimate on her V6.  Her husband was shocked that anyone could possible need the better part of $3k for a water pump, which showed up because of cam timing codes originally.

I showed him pictures, and he slowly shook his head...

Hi Streetwiseguy,

Am I correct in thinking that so long as the second row of seals is holding up, I’m OK unless the leak is coming from the sprocket bearing?

The Exploder is going in the shop on Monday…anything else I should be doing in addition to checking the oil dipstick for milkshake?

Thank you in advance for any guidance you can provide.

Streetwiseguy said:

I just made a Mazda CX9 owner very sad with my water pump estimate on her V6.  Her husband was shocked that anyone could possible need the better part of $3k for a water pump, which showed up because of cam timing codes originally.

Wow, and here I thought a grand for the water pump on my Duramax was bad.

And I was thinking only Chrysler was dumb enough to bury a water pump (wear item) under a timing chain cover. The engineer who designed that was evil.