Poll 2.5T Coolant Leak/Engine Replacement

[sm1ke]

Apparently that must have been another one of my senior moments

No worries, we all have those (or will have them eventually)

Did you mention the UOA to them and, if so, did they give any indication of being willing to consider it as proof of an internal leak?

No, I didn't mention the UOA as I wanted to see if they could find a leak first.

Result of the dealer visit. Basically they couldn't find a leak, even after asking them to take a second look just in case. I will be monitoring the coolant level until my next oil change, and then I'll be sending a second UOA out to see if K levels are still elevated, and take it from there.

 

[sm1ke]

To address the OP's question, basically what you can do is inspect your coolant level to ensure it doesn't drop over time (inspect it when the engine is cold). Check for telltale signs of a coolant leak (fluid pooling under the car or in/on the underside panels, sweet smell from the engine after driving the car). If you suspect a coolant leak, have the dealer perform an inspection to check for signs of a leak in the coolant system and on the back of the engine (all previously reported cases have stated that if coolant is leaking, it seems to originate there).

Aside from that, you can also perform UOAs periodically.

 

[edmaz]

.... Result of the dealer visit. Basically they couldn't find a leak, even after asking them to take a second look just in case. ....

Disappointing for sure, but also probably not a big surprise to you either. Did Mazda CA give you a 100K km powertrain warranty?

 

[sm1ke]

Disappointing for sure, but also probably not a big surprise to you either. Did Mazda CA give you a 100K km powertrain warranty?

Yes, to be honest I was hoping that they would find a leak. Strange, I know, but it would have been a definitive answer and I could get the leak repaired while under warranty. But I didn't think they'd find one if I wasn't showing any of the telltale signs from visual inspection.

Mazda Canada offers a 5yr/unlimited KM powertrain warranty on all vehicles, starting from 2015 onwards, so I should be covered until Dec 2022/Jan 2023 since I bought the car at the end of Dec 2017.

 

[edmaz]

Yes, to be honest I was hoping that they would find a leak. Strange, I know, but it would have been a definitive answer and I could get the leak repaired while under warranty. But I didn't think they'd find one if I wasn't showing any of the telltale signs from visual inspection.

Mazda Canada offers a 5yr/unlimited KM powertrain warranty on all vehicles, starting from 2015 onwards, so I should be covered until Dec 2022/Jan 2023 since I bought the car at the end of Dec 2017.

Wow, I wasn't aware of that unlimited mileage, time-based warranty, which is certainly a great deal for those who do lots of driving! And it's a really good thing for you to have the 1.5 year cushion, given this slow coolant loss that Mazda is currently not able to confirm.

Where you wrote 'repair' the leak, I'm taking 'repair' literally, and wondering if you would actually be ok if Mazda wanted to do a HG replacement, if that does turn out to be where the coolant is going. Now based on some of the information in the other threads, it sounds like they're just replacing engines with coolant leaks. So is that what you're actually presuming and expecting for yours as well when you say repair?

 

[sm1ke]

Wow, I wasn't aware of that unlimited mileage, time-based warranty, which is certainly a great deal for those who do lots of driving! And it's a really good thing for you to have the 1.5 year cushion, given this slow coolant loss that Mazda is currently not able to confirm.

Where you wrote 'repair' the leak, I'm taking 'repair' literally, and wondering if you would actually be ok if Mazda wanted to do a HG replacement, if that does turn out to be where the coolant is going. Now based on some of the information in the other threads, it sounds like they're just replacing engines with coolant leaks. So is that what you're actually presuming and expecting for yours as well when you say repair?

Yes - based on other's reports, I'm presuming and expecting an engine replacement if we can confirm that there is a coolant leak due to a cracked head or due to a failed head gasket.

With that said, if they wanted to do a HG replacement instead, I would probably fight it unless they could provide some assurances that the new gasket would not have the same issues as the original. I don't know what that would mean.. maybe a new gasket design or change in material, different torque specs? But as long as they could justify and explain to me that the HG replacement would be sufficient, I think I'd be okay with it. Of course I'd be hopping on here and other places to get advice and do more research to validate what the dealer might say.

 

[edmaz]

Yes - based on other's reports, I'm presuming and expecting an engine replacement if we can confirm that there is a coolant leak due to a cracked head or due to a failed head gasket. ....

Yep, exactly where I'd be with this as well, and it's really fortunate that you have that huge time window available. You can just wait for this slow leak to turn into something so big that even the worst stealership can't try to deny it. A nice situation for you indeed!

 

[Mazdiod2]

If it's leaking coolant into the oil I think that's pretty bad for the lubricating properties of the oil.

 

[andrewnds]

All I can say is that I plan to share as much information as I can from my experience. I have an appointment with the dealer today to get the car on a lift and see if they can locate the leak.

Can't wait to hear what you discover. Ask if this is a developing trend forsure and if and what has been done. As mentioned in other posts about this issue, part numbers have since been updated for the turbo's engine block. Maybe inquire if Mazda had made a change..

 

[sm1ke]

Can't wait to hear what you discover. Ask if this is a developing trend forsure and if and what has been done. As mentioned in other posts about this issue, part numbers have since been updated for the turbo's engine block. Maybe inquire if Mazda had made a change..

From an earlier post:

Result of the dealer visit. Basically they couldn't find a leak, even after asking them to take a second look just in case. I will be monitoring the coolant level until my next oil change, and then I'll be sending a second UOA out to see if K levels are still elevated, and take it from there.

 

[arock712]

Should the coolant reservoir always be near the Full line? Mine has about 5000 miles since last oil change and currently the line is still in the normal range, but has about 1/3 left until it gets to the Low line.

 

[sm1ke]

Should the coolant reservoir always be near the Full line? Mine has about 5000 miles since last oil change and currently the line is still in the normal range, but has about 1/3 left until it gets to the Low line.

So the coolant reservoir is an expansion tank, meaning the level will fluctuate depending on certain factors. My understanding is that the level will be higher if you look at it after shutting the engine off, and lower if the car has been sitting for a while. Since I didn't want to fiddle with the cooling system while the engine was hot, I checked it 2-3 hours after shutdown. I filled to the F line, but really I think I should have filled to maybe an inch below the F line to account for expansion.

In your case, what I would do is always ensure that you're checking the level in a consistent manner - for me, I'm checking a few hours after engine shutdown. If you notice that the level drops over a period of time, it might be a good idea to have it looked at.

 

[arock712]

So the coolant reservoir is an expansion tank, meaning the level will fluctuate depending on certain factors. My understanding is that the level will be higher if you look at it after shutting the engine off, and lower if the car has been sitting for a while.

When I first checked while the engine was warm, the reservoir was about halfway in the middle between full and low. A few hours later it was about 1/3 above the low. I'm having the oil changed next week and will see what the coolant level is going forward.

 

[PTguy]

The coolant level in the plastic expansion tank directly relates to the coolant temperature. The coolant temperature relates to both the load on the engine and the heat of the day. You want it above L when everything is cold, and you want it up to F after working hard on a hot day. The actual level isn't as important as having a consistent level at a consistent temperature.

 

[Trixstar]

I just checked my coolant on my 2019 with 60,000 kms. Its right above the Low mark. Should I be worried? Seems to eat through coolant. I don’t normally fill them on previous vehicles for ages

 

[Silly Wabbit]

I just checked my coolant on my 2019 with 60,000 kms. Its right above the Low mark. Should I be worried? Seems to eat through coolant. I don’t normally fill them on previous vehicles for ages

Was the engine Hot warm cold?

 

[Trixstar]

Was the engine Hot warm cold?

It was hot

 

[Trixstar]

I posted something on another forum.. They said its a coolant leak. Likely head gasket. Its definitely not normal for the coolant to go down to the Low mark in just 60,000 kms. I’m worried this could be problematic down the road as I didn’t purchase extended warranty and plan on keeping this vehicle for 5 more years. Never thought I might be one of the “few” with coolant loss. This is a downer. I’ll fill it up to under the High mark on a cold engine and observe.

 

[arock712]

They said its a coolant leak. Likely head gasket. Its definitely not normal for the coolant to go down to the Low mark in just 60,000 kms.

If you're still under the power train warranty why not have Mazda look at it?

 

[Trixstar]

If you're still under the power train warranty why not have Mazda look at it?

If you're still under the power train warranty why not have Mazda look at it?

I’ll call up Mazda tomorrow and book an appointment.