Coolant recovery tank

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2007 Mazda CX-9 Touring
I have disappearing coolant from my 9 and I saw a wet spot on the top rubber part of the motor mount. Does the recovery tank have a history of failing? I ran my finger on the hose that attaches to the tank the thin one and it feels a bit wet. I dried it out and put a rag to see if it leaks anymore. I also filled the recovery tank with fl-22. I will see what happens in the morning. Anyone else have this problem?
 
I have disappearing coolant from my 9 and I saw a wet spot on the top rubber part of the motor mount. Does the recovery tank have a history of failing? I ran my finger on the hose that attaches to the tank the thin one and it feels a bit wet. I dried it out and put a rag to see if it leaks anymore. I also filled the recovery tank with fl-22. I will see what happens in the morning. Anyone else have this problem?

oh-oh, bad sign, might be a bad water pump seal and the coolant is leaking into the engine thus you see the drop in coolant level, the coolant is a closed system and if everything is good there should be no drop in the level, quick check is to take out the engine oil dipstick and check to see if the oil looks like chocolate milk, if it is, you have coolant mixing in with the engine oil. the Ford design is crazy, they have the water pump right on the side of the engine, the water pump has a weak plastic impeller that "wobbles" over time and that stresses the o-ring seal until the seal fails and the coolant starts leaking into the engine.

https://www.mazdas247.com/forum/showthread.php?123845243-Water-pump!!!!

not saying it is a water pump seal failure, hopefully it's not but it's something to check.....
what year and how many miles do you have ?
 
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My mazda is a 2007 with 99,400 miles on it. This is the second water pump. Mazda replaced it at 66,800 miles. If this is true what you are saying then the dealer can't fix this right either. The first time it went there was no wet spots on the rubber part of the motor mount. It just started leaking down. It literally sounded like someone relieving themselves. I put coolant in it last night and it is still full. I guess this will be my last mazda. I babied this car through out its entire life. I will check again tonight and then check the oil. I just did the oil change about a week ago and the oil was golden brown almost the same color that it came out of the bottle.
 
this is an excellent video with the side engine cover removed
showing what happens when the water pump seal fails,

he pressurized the coolant system and you can see the coolant drip down to the oil sump tank.......
once the coolant gets into the oil sump tank (the same tank for engine oil changes)
the coolant gets distributed into the engine,

other video also shows the cheap plastic impeller disintegrating and the wobbling over time.....

really not a Mazda design, this is when Mazda and Ford were partners and Mazda used Ford parts.....
CX-9 is really a Ford Edge in disguise...not a true Mazda vehicle.

video is a Ford Edge but it's the same engine in the CX-9


 
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About 2 weeks ago the pump failed on my CX-9. I wish I had had a little warning, like seeing a leak etc. I can tell you run to check it out and don't drive it.. It caused my engine to fail. $4000+ later my engine had to be replaced. I was at 74500 miles no warranty. What I have since learned is the pump is located inside the engine compartment, and driven by the timing belts. I ended up with a milkshake for oil. I will be writing a separate post to possible help/warn others.
 
I added a little coolant 2 days ago and it is still there. I checked the oil and it is clean no milkshake color. I saw a drop of water or maybe it was coolant from the center of the front of the car ( radiator ). I also put a rag under the big hose in the coolant recovery tank to see if it leaks from that spot. I can understand the first pump going but the replacement going as well especially since I took it to the dealer. I would think that they would be capable of doing this job the right way. I will wait, check and see what happens. Also before I forget I was checking for an estimate on the water pump for the 2016 cx-9 and it costs the same to replace why is that? is this also an internal pump?
 
To mazda cx92013 when you said 4k for the engine was it exactly that amount or closer to 5 grand. Also was it a reman engine or used engine?
 
To mazda cx92013 when you said 4k for the engine was it exactly that amount or closer to 5 grand. Also was it a reman engine or used engine?

Exact amount was $3998.28 was quoted about $3500, but we purchased an additional warranty and all the liquids were replaced so it increased the cost and the final price also included a small tow fee. The engine was used with about 40,000 miles, not a rebuilt. I sought the advice of several mechanics, and three quotes all about the same. To repair my engine without knowing exactly what was wrong was looking at labor costs as well. Could have ended up about the same price after diagnosis and repair.

Everyone advised that in the future should it seem that is overheating to stop immediately and have it towed. Running a dry or leaking water pump in these cars is extremely costly.
 
OP could be a bad hose, coupling, or even overflow out the tube at the top of the reservoir if overheating.

Here's a test.
Coolant is less buoyant than oil and will sink to the bottom of the oil pan once cool.

The coolant wont completely separate out in a hot engine as the "milkshake" oil is something close to an emulsion, but if you let the engine cool overnight and then drain a bit from the oil pan, you will see coolant drain first if it's there. Think about vinegar and oil in the refrigerator.

If all you see is black used oil coming out of your pan, then your coolant is likely leaking elsewhere.

The 2016-2017 CX-9's are Mazda 4 cylinder turbo designs, so do not share the water pump issues. (They will have there own issues-LOL)
 
If it was overheating wouldn't the temp gauge go up? I always felt like maybe it was evaporating through the top tube. As of today the coolant returned to the overflow, very strange. I opened the cap to check the color and it is green like the fluid in the container of fl-22 fluid I have at home. I also check the oil on the dipstick and it is the same color as when I put it in 2 weeks ago. I probably have a leak somewhere. What I do notice about this coolant is that the smell is not as strong as the old style green coolant and it evaporates when it leaks on the ground. I opened the jug of my fl-22 to smell it and put a couple of drops on the ground and it was gone within 2hrs. The old style coolant would just stay there and you would see a green spot where it was leaking from. I am keeping an eye on it to see if I can locate the leak.
 
If it was overheating wouldn't the temp gauge go up? I always felt like maybe it was evaporating through the top tube.

Well yes and no. The temp gauges on these and most other modern cars are not really gauges at all; they are really just fancy warning lights. The gauge is center-weighted so that any temp in a certain range of "normal" operating temps will always show the needle in the middle. That "normal" range is very wide (50 degrees F is not uncommon) so if the gauge goes much beyond the center line, you are already headed for trouble and on the road to serious overheating. The time between the gauge rising past center and full-on overheating can be mere minutes in some cars.

The internal construction of the coolant reservoir is such that coolant would only come out the little rubber tube in an overheating or overfilled situation, so I very much doubt you're losing anything there unless the engine's actually overheating and forcing out the coolant.

Cars only use the reservoir to gain or release fluid during normal operation as the reservoir is not part of the active flow path for the coolant (nothing's pumping to/from there like the radiator). The coolant reservoir fills or empties based on pressure changes in the radiator and coolant jacket. Since pressure raises the boiling point in coolant (and any fluid), it is desirable and designed into the system. If the coolant boils and the pressure gets too high, it flows into the reservoir. When the engine cools off, the resulting vacuum sucks coolant out of the reservoir back into the radiator and engine.

BTW, The reservoirs so common today used to be aftermarket add-ons decades ago. I can remember people like my dad routinely adding them to cars to prevent overheating since back then the only way for the radiator to relieve pressure was by blowing the safety valve in the radiator cap. Once people added the extra reservoir (and check valve in the new cap), the overheating stopped as there was now an extra margin of capacity for the system when things got hot (happened a lot with early A/C systems overloading engine cooling) that didn't cause the system to boil off coolant and never get it back.

It is normal to have the coolant reservoir level go up and down between the High and Low marks during normal use. In fact, after you do a full coolant replacement, you usually need to add a little bit of fluid every day for the first few days as the air works it's way out of the system even if you follow the manual's bleed instructions. Check the level when cold before starting the engine. When hot, levels will likely be higher due to thermal expansion.

On the other hand, if the levels are dropping and not coming back up, then you are truly losing coolant. It's either burning (head gasket... white smoke), boiling (water pump, steam comes out when you open oil filler cap, chocolate milk oil) or leaking (real leak or being blown out the overflow).

I would check the cap on the reservoir to be sure it's holding pressure as a bad one can lead to coolant being blown out the overflow tube.

Assuming no leaks or other issues, you also need to figure out why the engine is forcing so much coolant into the reservoir in the first place since that only happens when overheating begins. Bad pumps, thermostats, clogged radiators, and faulty cooling fans are the suspects there.
 
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We can probably get a warning of this by getting an oil analysis done from time to time. The analysis would pick up the slightest trace of coolant in the oil.
For my BMW, I was able to fix my head gasket before it would become a big problem.
 
There is a weep hole in between the alternator and ac compressor. I had the leak on the coolant reservoir dripping it on the side motor mount. Thought it was overflowing but the hose was bad. Replaced the hose. No leak. But then a couple of weeks it still loosing coolant and its dripping on the ac compressor. And there the water pump again failing. Will be replacing the water pump again I guess. Fml.
 
Who replaced the water pump the first time? was it you or a dealer, mechanic? How many miles did the replacement last, I am on the second water pump and so far have about 35k on it. Was replaced by the mazda dealer.
 
Update: I noticed dripping from the center of the car. When I got home I checked the drain plug. I first tried to tighten it with my hand. I noticed that it was very loose so I start turning it to tighten and noticed it dripped more so I went in the opposite direction. Long story short the head of the drain plug came off. It is now dripping into a drain pan. What are my options here. Would I be able to remove the remaining piece of the drain plug still in the radiator or do I need a new radiator? I would appreciate it if I can get some input soon as I need my car to run my errands. Thanks in advance.
 
the Ford design is crazy, they have the water pump right on the side of the engine, the water pump has a weak plastic impeller that "wobbles" over time and that stresses the o-ring seal until the seal fails and the coolant starts leaking into the engine.

No, it's not a ford design. ford doesnt design anything and especially not Mazda's engines. you can thank Mazda's engineers for that one. most likely did it for better space management and packaging.
 
No, it's not a ford design. ford doesnt design anything and especially not Mazda's engines. you can thank Mazda's engineers for that one. most likely did it for better space management and packaging.


Sorry man, but you are wrong again!

FORD MOTOR.
AISIN TRANSMISSION
FORD AWD DIFF
 
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