Video of belt tensioner leaking and leaking timing cover gasket

First of all with my first post here, I'd like to say thank you to all who contribute here. I also want to acknowledge that there is already good information posted in these forums about what to think and/or do about a leaking bent tensioner and leaking timing cover gasket. I had a Mazda dealership recently perform an oil change on my 2015 Mazda CX-5 GT and mid-service they provided a video and recommendation for replacing the drive belt tensioner for $451.00 and also timing cover gasket for $911.80. I attached a slightly edited version of the video I received. I edited the continuous video to take out my license plate in the beginning and end. This is no doubt my vehicle. I declined the services. What do you think about the findings that are shown in the video? I'm thinking I need to do my own investigation? This is the first time I've ever experienced getting a video like this and wanted to share it here. Thank you in advance to anyone who takes a moment to chime in! 2015 Mazda CX-5 with 51k miles as of October 3rd 2020.
 

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OP,
I think your dealer guessed where the oil came from. So, they prescribed tensor replacement and gasket. Did they tell you why they think so?

Firstly, for only 51k, your engine bay is dirty. Did you own it from new?
Secondly, my tensor looked like yours on my '16 Mazda6 (45k). There was some oil stain on the alternator also. I suspected that someone spill the oil while filling the engine oil.

Anyway, I cleaned up the stains, and keep checking it every weekend.
So far, I have seen 0 sign of fluid leak.

On the web, I have read that some bad mechanics intentionally spill some engine oil. Later on, they tell owners to replace this and that due to fluid leak. Need to protect our wallet.

My recommendation: Clean up the stains and keep an eye on the engine.
If stain shows up again, you got a real problem to fix.
 
OP,
I think your dealer guessed where the oil came from. So, they prescribed tensor replacement and gasket. Did they tell you why they think so?

Firstly, for only 51k, your engine bay is dirty. Did you own it from new?
Secondly, my tensor looked like yours on my '16 Mazda6 (45k). There was some oil stain on the alternator also. I suspected that someone spill the oil while filling the engine oil.

Anyway, I cleaned up the stains, and keep checking it every weekend.
So far, I have seen 0 sign of fluid leak.

On the web, I have read that some bad mechanics intentionally spill some engine oil. Later on, they tell owners to replace this and that due to fluid leak. Need to protect our wallet.

My recommendation: Clean up the stains and keep an eye on the engine.
If stain shows up again, you got a real problem to fix.

The dealer service department did not say how they came to their conclusions and recommendations.

Dirty engine bay: I am the only and original owner. I guess I should be cleaning the bay. Do you have any recommended products or just good ol' soap and water?

I will clean up the stains and continue to watch for now, thank you!
 
if timing chain cover 'gasket' is leaking badly, oil usually drips to the bottom over time. you can remove the under engine cover shield and take a peek if you have a way to go under.
it is a known issue over time but I think we have seen it mostly on gen2 based on older email threads here.

for the belt tensioner , thats a known issue too for most recent years/model. its a bit hit and miss when and if it happens.
See few threads back in the list.

I would still verify in your case to be sure it is what they say it is. May be go to indie shop or even another dealer just for a 2nd opinion if you are unable to confirm on your own. 1300+ usd is bloody expensive. Although the timing cover sealing is a lot of hours and work to fix. That would be costly in any case.
 
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If this is a known issue why hasn't there been a class action lawsuit that could force Mazda to extend an engine/transmission warranty to 100 thousand miles?
 
If this is a known issue why hasn't there been a class action lawsuit that could force Mazda to extend an engine/transmission warranty to 100 thousand miles?
I don't disagree with this mentality. I am personally in contact with Mazda USA at this point in time, they are supposedly investigating my particular case at this time. Do you have any further suggestion with regard to initiating a class action lawsuit in this kind of situation?
 
I don't disagree with this mentality. I am personally in contact with Mazda USA at this point in time, they are supposedly investigating my particular case at this time. Do you have any further suggestion with regard to initiating a class action lawsuit in this kind of situation?

I don't as I am not a lawyer but there have been a few against Subaru over the years.
 
what was the date you bought the cx5? if it's not still under warranty it might be close enough that Mazda corporate will ok a goodwill warranty repair for the timing belt cover
 
its a known issue in the forum.
and there are some tsbs.That doesnt mean it affects milion cars :)
You cant be serious with this lawsuit talks mate. Its not like the car will explode in flames.
 
Welcome and thanks for joining up and sharing your issue, @somnief. You've definitely come to the right place, I see you've already received helpful responses...Please do keep us updated and I hope everything works out!
 
First of all with my first post here, I'd like to say thank you to all who contribute here. I also want to acknowledge that there is already good information posted in these forums about what to think and/or do about a leaking bent tensioner and leaking timing cover gasket. I had a Mazda dealership recently perform an oil change on my 2015 Mazda CX-5 GT and mid-service they provided a video and recommendation for replacing the drive belt tensioner for $451.00 and also timing cover gasket for $911.80. I attached a slightly edited version of the video I received. I edited the continuous video to take out my license plate in the beginning and end. This is no doubt my vehicle. I declined the services. What do you think about the findings that are shown in the video? I'm thinking I need to do my own investigation? This is the first time I've ever experienced getting a video like this and wanted to share it here. Thank you in advance to anyone who takes a moment to chime in! 2015 Mazda CX-5 with 51k miles as of October 3rd 2020.
You have a 2015 Mazda CX-5 with 51K miles, and you’re out of 5-year / 60K-mile powertrain warranty which will cover timing-chain cover leak. You can try to contact Mazda North American Operations for some help as you just did. But don’t expect too much from MNAO at this stage.

Timing chain cover leak problem seems to be lesser than belt tensioner leak, and both have TSB’s issued by Mazda. Timing chain cover leak is very difficult to fix as there’s no gasket, and the RTV sealing is very tricky due to the 2-piece cylinder block design on SlyActiv-G engines. One member here was trying to fix the leak several times by Mazda dealer under warranty, but until today it still has some seepage from it.

Belt tensioner leak is more common and a lot easier to fix, if you can get the latest version OEM tensioner and hopefully it won’t leak again like previous version.

Hard to tell if your timing chain cover is truly leaking from the video, but usually timing chain cover leak won’t be “severe” and more like the “seepage”. If I have such problem on my CX-5 without warranty, I‘m not going to fix it due to the difficulty of the repair, and there’s no guarantee it won’t have seepage again.

And yes, your belt tensioner is leaking.
 
its a known issue in the forum.
and there are some tsbs.That doesnt mean it affects milion cars :)
You cant be serious with this lawsuit talks mate. Its not like the car will explode in flames.
A class action lawsuit on failed transmission was filed against Toyota by a California couple recently because their 2018 Highlander XL is having the pattern of hesitation and surging. Anyone can file a class action lawsuit as long as there’s a lawyer who is willing to take your case.
 
It's not a bad idea to change the brake fluid at 50K or 60K miles. Over time it does absorb moisture. Not sure about a fuel system clean, or what they do to clean the fuel system. I don't think I would pay for the timing chain cover seal to be replaced at that price, especially if the oil level doesn't go down much between oil changes. It looks like a slow leak to me.
 
No issues with my tensioner but do I have to clean up my seep/weep on rear timing chain cover every 3-4 months. It is the same location as OP and was repaired under warranty but then came back. It does seem to be a variable seep/weep... sometimes it is worse than other times. I don't know if temp or load related. I just live with it now. It doesn't lose anything noticeable between oil changes and everywhere else on engine is dry. I did have a rear main seal replaced on mine as well.
 
... Timing chain cover leak is very difficult to fix as there’s no gasket, and the RTV sealing is very tricky due to the 2-piece cylinder block design on SlyActiv-G engines. One member here was trying to fix the leak several times by Mazda dealer under warranty, but until today it still has some seepage from it. ...

I've had good success in the past stopping slow oil pan gasket leaks and weeps by applying RTV to the outside of the gasket, in the area of the leaking, along with tightening up pan bolts in the leak area. And, although I've never needed to do this on a timing cover, I don't see any reason why the same technique wouldn't work there as well. There's not a huge amount of pressure at the gasket, so firmly attached RTV should be enough to block the flow. At least that's how its worked for me on oil pan gaskets anyway.

That said, getting complete access to all of the timing cover gasket would be much more challenging than the gasket on an oil pan. And it wouldn't surprise me if some portions are basically inaccessible, unless the part(s) blocking access are removed. I have not removed the underbody splash guard on my Mazda yet, so I don't have any idea at this point of what access to the lower block is like from under the vehicle. Perhaps someone else here can give their hands-on perspective of how it actually is.

But for the amount of work (or $$) that would be required to remove, reseal, and reinstall the cover, I would absolutely give it my best effort before giving in and doing the much larger project. Particularly in a case like this where the much larger job might not even be successful. The steps involved for the 'patch' job are quite simple, and are well within the capabilities of most any DIYer who is willing to put in the required time and effort.

First, as mentioned in this thread previously, the entire area of the leak (including everything above it) needs to be cleaned well. Then the vehicle gets driven and rechecked, until the point(s) of the leak are identified. Then, if the leaking is confirmed to be at the timing cover gasket, the area is cleaned again, with all oil residue removed from the actual gasket area.

Once the leak area is completely clean, a small amount of RTV such as Permatex Black is applied over the gasket and smoothed out, leaving a nice solid layer covering the leak area, including overlapping the metal on both sides. After all of the required RTV is applied, wait about an hour, and then re-torque to spec (usually around 100 in-lbs) all of the timing cover bolts that are in the immediate area of the leak. And of course some bolts may also be blocked and inaccessible.

Again, it might be very difficult (or impossible) to do this work in some sections of the cover, but I'd have no problem giving it a really good try, keeping in mind that small tools might be able to get to places where fingers cant go. And for any areas which do get covered with RTV, I'd expect there to be a very good probability of long term success in stopping the leaking. And if this patching job does stop the leaking, then rechecking the tightness of the cover bolts periodically would be highly recommended.

Edited to add letting the RTV fully cure for 24 hours before driving if possible.
 
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I've thought about... in fact have a can of this Permatex spray and will attempt at some point.


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"A sprayable sealer that forms a durable rubber barrier that stop leaks in minutes. The wicking action seals hard-to-reach leaks without the need for disassembling or removing parts. Designed specifically to target low pressure leaks in hoses, oil pans, differentials, transmission pans, fluid reservoirs as well as plastic, PVC and metal pipes, their connections and much more!. Eliminates the need for liquid additive sealers that can swell and foul internal seals. Resists common shop fluids. Note: In many cases, more than one coat will be needed to solve the problem. Level 3"

"
Automobile
Suggested Applications: Engine and transmission leaks, hoses, oil pans, differentials, transmission pans, cooling systems, thermostats, water pumps, valve covers, tubing connections, electrical harness connectors, plastics, and PVC."
 
I've thought about... in fact have a can of this Permatex spray and will attempt at some point. …
I've never used the spray, so I can't offer any first hand experience on it. I will say that this gasket patching wants to be very localized, and the RTV should be pressed into the surfaces, in order for good bonding to take place. And the layer needs to be beefy enough in order to not break down or crack over time.

Again, I can't say how the spray would work, but I have a feeling it would tend to go all over the place (i.e. not where it's needed or wanted), in order to get a good amount where it is needed. But that's just a guess, and I certainly could be wrong about that. OTOH the spray might be able to get into a place where the tube stuff can't be applied, so it could very well be the winner in that case.

If you do try it, I'd be interested how it turns out, so please post back with your results.
 
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