2017~2024 Timing cover seal and coolant flange issue

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In service right now. 2nd time the timing cover seal has failed on my 2018. They said it’s because the tech did a poor job and that this time the master mechanic was going to do it. I’m a bit concerned as I was in December of 2019 for the exact same issue and was assured once they fixed it, it should be good to go.

Was also informed that a coolant flange has signs of possible leaking and that they would replace it with an “updated” part. Anyone had this issue?

Im getting a little nervous with some of these issues, especially the timing cover.
 
Its covered under warranty. Dont worry just let them try to fix it. The sealant for the timing chain cover oil leak is known issue unfortunately. Few of us had it as well.
No idea for the flange. its a separate item not related to the timing cover.
 
Its covered under warranty. Dont worry just let them try to fix it. The sealant for the timing chain cover oil leak is known issue unfortunately. Few of us had it as well.
No idea for the flange. its a separate item not related to the timing cover.

yeah it specifically said “water pump inlet”. My service guy said he’s been seeing it more frequently so also seems to be an issue. He made it sound like there is an updated part, so we’ll see. Unfortunately have to go back Monday because mechanic is backed up.
 
In service right now. 2nd time the timing cover seal has failed on my 2018. They said it’s because the tech did a poor job and that this time the master mechanic was going to do it. I’m a bit concerned as I was in December of 2019 for the exact same issue and was assured once they fixed it, it should be good to go.

Was also informed that a coolant flange has signs of possible leaking and that they would replace it with an “updated” part. Anyone had this issue?

Im getting a little nervous with some of these issues, especially the timing cover.
From several members here who have had this oil leak on timing chain cover, the dealer most likely couldn’t fix it even though there’s a TSB for this issue. But the fix procedure is very complicated and dealers seem to have a hard time to follow and fix the problem properly. And I agree with madar that the rare design of 2-piece cylinder block should be the contributor of this timing chain cover leak. Unfortunately the detail of the TSB is gone in that long thread due to our server update.

Do ask your Mazda dealer about the TSBs on 2 problems you have and post them here.

So, the block is actually 3 pieces- head, cylinder block, and lower cylinder block, with the timing chain cover connected to both bottom pieces. Yikes! I'm surprised this thing doesn't have more leak problems.

(rant)

Hard to believe I have been dealing with this leak for 3 years now. I still have the timing chain cover leak as well that was already fixed but opened back up. I did an oil change last night and if I didn't have the plastic splash shield on bottom of car there would be oil droplets in the garage from this "LEAK". Patience gone and done.

My worst tuned two stroke old power sport beater motor is dryer than this thing. I think we are long past any residue leftover from manufacturer as previously suggested by service department. Back to dealer.

My secondary timing chain cover leak shows a lot residue around the upper rear pulley area. IIRC this was where it leaked from before. I've cleaned off several times with brake cleaner too.

just looked without removing the undershields.
Same story...leaking...on a new car..
seems Mazda have not really resolved or I am just unlucky.

Got a new oil pan, but I'm 99.99999% sure that wasn't the problem. I can look down from the top and see a film of oil alongside the timing cover as you can see in the picture I provided, collecting at the oil pan area and then running off onto the plastic undercover. Also pointed this out to the tech.
 
Yikes....yeah clearly bad design. Hopefully the master mechanic can do a better job. supposedly has been there 25 years. From other posts it doesn’t seem detrimental, but is definitely annoying.

supposedly the coolant inlet he said there is no TSB but I’ll ask again, because it sounded like it was becoming an issue
 
yeah worst case it will 'sweat oil' and may be collect small drips over longer time. its not leaking much but its annoying on a new car. Changing the sealant in perfect way is indeed a bit complex with the engine in the car.

Regarding the coolant inlet, there is one major metal inlet at the rear of the engine block. lots of water pipes go into it. Its seems a pain to change judging by the location.
The other inlet that comes to mind is the one in the front near where the thermostat is.

Anyway, go ask them to fix. Plan to leave the car there for a day at least. It takes some time to fix and cure the sealant properly and for the coolant inlet they have to take some coolant out to do the work.
Shame to have to deal with these on a 2018 car. Good luck and dont worry.
 
thanks cz5gt! Yeah they didn’t specify for the inlet so I’ll have to ask. He said you could see some dried up coolant around the connection, but it wasn‘t a major issue from what it sounded, Definitely frustrating since it’s a newer vehicle, but other than that I love it.

I had a loaner last time and plan on it again. Don’t want them rushing on it, so hopefully they can get it figured out this time around.
 
I've been getting a slow oil "seepage" over the last year and a half, some film on mating surfaces, no real drips, so I'm saying I'm good for now.
 
Finally got my car back. After trying to repair timing cover, there was a “bent” o ring and they had to order a new one.

For the timing cover leak, they said supposedly from the first time they tried to repair, there was an issue with an O ring from the cylinder deactivation oil control solenoid. As a result, there was oil leaking and it didn’t allow the RTV Silicone to cure properly, causing it to leak again along with the solenoid,

As for the coolant leak, it was from the water pump inlet. I guess the one positive is that I got some fresh coolant out of it,

Hopefully I’m done with the timing chain leak for a while and no other issues arise.
 
Finally got my car back. After trying to repair timing cover, there was a “bent” o ring and they had to order a new one.

For the timing cover leak, they said supposedly from the first time they tried to repair, there was an issue with an O ring from the cylinder deactivation oil control solenoid. As a result, there was oil leaking and it didn’t allow the RTV Silicone to cure properly, causing it to leak again along with the solenoid,

As for the coolant leak, it was from the water pump inlet. I guess the one positive is that I got some fresh coolant out of it,

Hopefully I’m done with the timing chain leak for a while and no other issues arise.
Thanks for the update! Still I’d keep my eye on the timing chain cover area from time to time if I were you just in case.
 
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I keep a can of brake cleaner to clean things up once and a while on my leak/weep. It sucks being in the area of the belts. Total hack job/bandaid but read enough reports of it working might give it a shot.


"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"

Screen Shot 2020-06-13 at 2.24.37 PM.png
 
In service right now. 2nd time the timing cover seal has failed on my 2018. They said it’s because the tech did a poor job and that this time the master mechanic was going to do it. I’m a bit concerned as I was in December of 2019 for the exact same issue and was assured once they fixed it, it should be good to go.

Was also informed that a coolant flange has signs of possible leaking and that they would replace it with an “updated” part. Anyone had this issue?

Im getting a little nervous with some of these issues, especially the timing cover.
I had to do mine twice as well. After first repair, we smelled burning oil in the hvac all the time. Since Mazda warned us it might still smell from residual oil burning off, we didn't think anything if it at first. A week later, and I saw a decent amount of oil on my garage floor. Lifted hood and oil had sprayed everywhere under the hood! Like it was under pressure. I think it has something to do with the hla's and cylinder deactivation. They replaced my hla's for free shipping with a new gasket. Part number for hla ended in 100A which, according to dealer, means updated design. We'll see what happens. Now I've got this to contend with https://www.mazdas247.com/forum/index.php?threads/transmission-issues-loss-of-power.123875201/
 
⋯ They replaced my hla's for free shipping with a new gasket. Part number for hla ended in 100A which, according to dealer, means updated design.
There’re 2 different hydraulic lash adjusters / valve lifters for cylinder #1、#4 and cylinder #2、#3. Unfortunately there’s very limited info on these parts online. I found valve lifter PYFA-12-100A which should be the one your dealer was referring to, but can’t tell if it’s for which cylinders. Would you mind to post the parts info on your repair invoice?

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There’re 2 different hydraulic lash adjusters / valve lifters for cylinder #1、#4 and cylinder #2、#3. Unfortunately there’s very limited info on these parts online. I found valve lifter PYFA-12-100A which should be the one your dealer was referring to, but can’t tell if it’s for which cylinders. Would you mind to post the parts info on your repair invoice?

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I will as soon as my wife finds and emails me the paperwork.
 
I will as soon as my wife finds and emails me the paperwork.
Just an FYI that it's always much better for any problem discussion to just post on one thread. If there are separate conversations going on in multiple threads, the information is likely to not be shared as well as when it's all in one place. And IMO the thread that you started would be the best place for this discussion to continue.

However, if you eventually have an outcome that applies to discussions in multiple threads, and might benefit other readers, then it's certainly ok to post that information in all of those threads. JMO, based on spending time on many forums over quite a few years.
 
Just an FYI that it's always much better for any problem discussion to just post on one thread. If there are separate conversations going on in multiple threads, the information is likely to not be shared as well as when it's all in one place. And IMO the thread that you started would be the best place for this discussion to continue.

However, if you eventually have an outcome that applies to discussions in multiple threads, and might benefit other readers, then it's certainly ok to post that information in all of those threads. JMO, based on spending time on many forums over quite a few years.
I believe these issues to be related but I see what you're saying.
 
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