Ford Duratec 3.7 Water Pump Failure

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I ran across some information on my Mazda’s (Ford) Duratec 3.7 V6. Looks like the Water Pump is internal to the engine and driven by the timing chain. Any failure by gasket or pump can trash the engine quickly by spilling coolant into the oil.

I read somewhere the 2012’s have a beefed-up impeller making the failures less common. I hear the engine must be taken out to fix which can be costly. Currently have 57,800 miles.

Anyone have any info on how common it is?
 
Friends son had one that disintegrated internally, toasting the engine. Not a design I would want to own!
 
That is what is making me think I should trade in...really would hate a car payment again. Appreciate the info...do you know what year your friends son had?
 
Let me get my head around this. Ford's latest OHC V6 has a timing chain driven WP that leaks coolant into the crankcase. Should you catch this before the bearings are destroyed, the engine has to come out to fix. Oh goody, the impeller was beefed up. I've known impellers to fail, but the most common WP mode of failure is leaking seals and bad bearings. I'm not a big fan of OHC V-6s. Combined with Ford's just barely make it out of warranty philosophy..
Sounds like a perfect lease car. Sell before the warranty expires.
 
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That is correct. I am embarrassed to say I missed that design fact when initially purchasing the car. The car has been great no problems other than a few recalls...just concerned about my planned long term ownership.
 
Wait just a minute! If this is similar to the set up on the 3.5 Ecoboost that hub on the timing chain is simply an idler. Check this post with pictures.....

http://www.f150ecoboost.net/forum/6-f150...r-pump-buy.html

You might be in luck. On the EB the timing chain thing, it is listed a pump but it really isn’t...
Notice in the pictures on the link the so called timing chain pump has no room for impellers or anything else.
Hope this helps!
 
The original 3.5L Duratec V6 has a special drain channel cast into the front timing cover that will allow any coolant seepage from WP bearings to drain to exterior of engine. If this is to be trusted, and if your WP is going to leak at bearing before failure - then you could inspect the outlet of this channel (behind alternator) for any evidence of coolant.

The WP job is nasty, but it can be done with the engine in place - assuming you have normal size hands and forearms, if not the engine should be removed. There is a video on YT for this work.
 
The rule is this:
  • Transverse mounting Ford/Mazda 3.5/3.7 engines (including Ecoboost), the pump is internal to the engine and driven off the timing chain. Packaging issues they say.
  • RWD mounting (Mustang, F-series, Full Size Transit, including Ecoboost) 3.5/3.7 are regular old water pumps external to the engine. No packaging issues, so they say.


Ford and Mazda have had this engine in lots of high volume vehicles since 2007. Failures can take the engine out but seem to not be a huge issue. I've got 122k on the original water pump in mine and I'm not concerned. Keep an eye on coolant level and weep hole, change when required, and keep an eye on the color of the oil.

If it's paid for I'd not worry about it as, IMHO taking on a car payment now for something that may or may not fail is a little over reactionary.
 
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Double vanos, I believe it is the same setup that is on the 3.5L Duratec V6. I believe the 3.5L ecoboost is a better design. Maybe someone knows more. Appreciate the input.
 
itguy08, thanks for the clarification. Well said. I do keep an eye on coolant and oil throughout OCI. Will have to track down weep hole as well. Not too concerned (not keeping me up at night). At least I know possible weak points to look out for. Thanks to all again.
 
Maybe bdcardinal could take a look at the actual part for us and see if the chain driven part is actually a pump or merely a crossover channel cover like the link I put up. Curious to how this plays out. All this proves that it pays to really be informed about what you’re buying before you buy it.
 
Me too double vanos. I appreciate the info. Looked at the reviews but missed the engineering realities. Hope I am one of the lucky ones.
 
Yep. I asked this same question some time ago. Like itguy said, this effects the FWD versions of these V6s ONLY. I'm wondering if coolant swaps more often can help prevent it.
 
We haven't seen that many of these go bad. A bunch more of the RWD configurations in F150s and Mustangs. Luckily for our techs we have a powertrain lift so the job isn't too bad. Some techs have supposedly figured out how to do it in vehicle, but it has to be pretty miserable.
 
My beloved 2009 Mazda 6 3.7L just had a catastrophic engine failure on Saturday at 126K. Either get rid of it or replace the water pump if you are near 100k.
 
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