2013~2016 Belt Tensioner - Shouldn't this be a warranty item?

yrwei52

2016 Mazda CX-5 GT AWD w/Tech Pkg
Contributor
:
Plano, Texas, USA
the prices here are high total of the part and labor was 350 us$.
Not sure which area is yours, but yep it’s high for a belt tensioner replacement even with OEM part. But as long as he did a good job, that’s all that counts.
 
:
13' CX-5 and 16' Mazda6 both Touring w/Tech/Bose
I had a car with a true hydraulic chain tensioner that could do serious engine damage if it didn't operate properly. It was screwed into the block and fortunately easy to replace.

I don't really understand the function of the oil in the Mazda tensioner but it doesn't appear to be constructed the way a hydraulic part is. There doesn't seem to be a cylinder and piston, just a rubber boot over a spring. This is why I don't see as much concern over replacing the part unless it actually seems to cause a more obvious problem, at which time I would replace the tensioner and belt together.

It would be interesting to see how the aftermarket part from Rock auto works. It looks different than the OE part.

I just hate seeing something leak. Its a mental thing for me. Reading the TSB again, the verbiage really does sound like Mazda had a host of customers concerns/complaints vs actual verified damage. In fact, there's no verbiage like "damage", "urgent", "danger", "immediate", ect.

"To eliminate this concern, the shape of the drive belt auto tensioner damper has been changed."
" Customers having this concern should have their vehicle repaired using the following repair procedure. "
" This warranty information applies only to verified customer complaints on vehicles eligible for warranty repair."


So imho its a short term visual concern on a part that will eventually have to be replaced in the long term (bearings in the pully will rattle over time). I used to stay up thinking about the damn tensioner but not so much these days. My concern level went from 8 to like a 5.
 
i could have waited until it starts to make noise or rattle and thats what my dealership advised me,they said it leaks but never really fail. but i cant drive knowingly there is a malfunction in my car.
with two little kids i need to know the car is safe and relible.
 

yrwei52

2016 Mazda CX-5 GT AWD w/Tech Pkg
Contributor
:
Plano, Texas, USA
I just hate seeing something leak. Its a mental thing for me. Reading the TSB again, the verbiage really does sound like Mazda had a host of customers concerns/complaints vs actual verified damage. In fact, there's no verbiage like "damage", "urgent", "danger", "immediate", ect.

"To eliminate this concern, the shape of the drive belt auto tensioner damper has been changed."
" Customers having this concern should have their vehicle repaired using the following repair procedure. "
" This warranty information applies only to verified customer complaints on vehicles eligible for warranty repair."


So imho its a short term visual concern on a part that will eventually have to be replaced in the long term (bearings in the pully will rattle over time). I used to stay up thinking about the damn tensioner but not so much these days. My concern level went from 8 to like a 5.
I believe the oil leak on belt tensioner is related to some rattling noises as mentioned in the TSB. The noises the TSB referring to should be from the vibration of the tensioner pulley or the damper itself due to the failing damper, not the failed bearing on pulley. But like the oil leak on shock absorber, this problem is not an urgent issue which needs to be resolved immediately.

Technical Service Bulletin
Mazda North American Operations Irvine, CA 92618-2922
Bulletin No.: 01-019/19
Last Issued: 11/26/2019

Subject:
OIL LEAKAGE FROM DRIVE BELT AUTO TENSIONER AND RATTLE NOISE FROM ENGINE COMPARTMENT

DESCRIPTION
Some vehicles may exhibit oil leakage from the drive belt auto tensioner and rattling noises from the engine compartment. This may be caused by insufficient sealing at the drive belt auto tensioner damper when the auto tensioner fully operates under both high ambient temperature and high load conditions. To eliminate this concern, the shape of the drive belt auto tensioner damper has been changed.
 
:
Pueblo county CO
:
CX-5 Sport 16.5 6M
I took a look at mine on the 2.0L. It looks like I could just unbolt it and replace with the only real obstacle being the serpentine belt.
 
:
16.5 CX-5 Tour/AWD
11/20 Update (After driving 1,700 Miles):

Hey guys, I just wanted to follow up on the thread after driving about 1.7k miles. So today I think I finally figured out 50-75% of the problem I'm experiencing with why I felt that after replacing the belt tensioner, my acceleration feels worse. Previously, before replacing the belt tensioner and the water pump/serpentine belt, I had a blast driving the car especially on highways and going from 0 - 60+.

Stomping/mashing on the pedal felt effortless and it didn't really take much for the car to rev up really high and start flying past everything. However, after replacing the belt tensioner all of this fun started to disappear and today I have slightly figured it out. I think most of us are aware of the little activation button on the bottom of the gas pedal (a.k.a Pedal Kickdown Switch) once you press down all the way. I never had to press the pedal all the way down until I heard a click but today after messing around and stomping on the gas pedal repeatedly, the car felt alive again.

The very strange thing is, why did this occur after replacing the belt tensioner/water pump belt and serpentine belt? I still enjoyed the OEM belt tensioner more as I did not have to press down until I hear a click.

Here's some possibilities that I can think of that may have changed the personality of my car:
  1. NON-OEM Belt tensioner: Stiffer design/different lubrication/different wheel bearings/Still not broken in? IDK
  2. Maybe I didn't bleed out the air from the belt tensioner correctly?
  3. Maybe there's some calibration that needs to be done?
  4. Maybe that's how my car was supposed to feel and replacing the OEM belt tensioner brought my car back to the factory shape?
I'm not sure how I feel about this as I was planning to put my OEM one back in because I definitely missed that personality of the car a lot more. Also, I did try Googling around to see if anyone has experienced the same issue as me but I don't think it's very common.

1605899668932.png

1605899679837.png
 

yrwei52

2016 Mazda CX-5 GT AWD w/Tech Pkg
Contributor
:
Plano, Texas, USA
11/20 Update (After driving 1,700 Miles):

Hey guys, I just wanted to follow up on the thread after driving about 1.7k miles. So today I think I finally figured out 50-75% of the problem I'm experiencing with why I felt that after replacing the belt tensioner, my acceleration feels worse. Previously, before replacing the belt tensioner and the water pump/serpentine belt, I had a blast driving the car especially on highways and going from 0 - 60+.

Stomping/mashing on the pedal felt effortless and it didn't really take much for the car to rev up really high and start flying past everything. However, after replacing the belt tensioner all of this fun started to disappear and today I have slightly figured it out. I think most of us are aware of the little activation button on the bottom of the gas pedal (a.k.a Pedal Kickdown Switch) once you press down all the way. I never had to press the pedal all the way down until I heard a click but today after messing around and stomping on the gas pedal repeatedly, the car felt alive again.

The very strange thing is, why did this occur after replacing the belt tensioner/water pump belt and serpentine belt? I still enjoyed the OEM belt tensioner more as I did not have to press down until I hear a click.

Here's some possibilities that I can think of that may have changed the personality of my car:
  1. NON-OEM Belt tensioner: Stiffer design/different lubrication/different wheel bearings/Still not broken in? IDK
  2. Maybe I didn't bleed out the air from the belt tensioner correctly?
  3. Maybe there's some calibration that needs to be done?
  4. Maybe that's how my car was supposed to feel and replacing the OEM belt tensioner brought my car back to the factory shape?
I'm not sure how I feel about this as I was planning to put my OEM one back in because I definitely missed that personality of the car a lot more. Also, I did try Googling around to see if anyone has experienced the same issue as me but I don't think it's very common.

View attachment 229021
View attachment 229022
This’s really odd. Is there any difference on gas mileage before and after? Did you disconnect the battery while replacing the tensioner and belts? I believe you use OEM belts so you won’t have problem like minnesotaart who used shorter Dayco stretch water pump belt. IMO your Gate tensioner should not give you the problem you described. Something else happened during your belt and tensioner change.
 
:
Pueblo county CO
:
CX-5 Sport 16.5 6M
I wonder what causes some tensioners to leak? Lot's of higher RPM operation?

I guess when revving high the belt is flailing back and forth causing excessive motion in the tensioner?

It would be hard to imagine how that could affect power output from the engine.
 

yrwei52

2016 Mazda CX-5 GT AWD w/Tech Pkg
Contributor
:
Plano, Texas, USA
I wonder what causes some tensioners to leak? Lot's of higher RPM operation?

I guess when revving high the belt is flailing back and forth causing excessive motion in the tensioner?

It would be hard to imagine how that could affect power output from the engine.
In my case it’s definitely not from a lot of higher RPM operation. My 2016 CX-5 at 41K miles with leaky belt tensioner rarely sees engine revolution higher than 3,000 rpm or any heavy load. Based on the TSB, it’s simply caused by poor design and quality (insufficient sealing on damper), hence the tensioner damper needs to be modified.

TSB 01-019/19
OIL LEAKAGE FROM DRIVE BELT AUTO TENSIONER AND RATTLE NOISE FROM ENGINE COMPARTMENT

Description:
Some vehicles may exhibit oil leakage from the drive belt auto tensioner and rattling noises from the engine compartment. This may be caused by insufficient sealing at the drive belt auto tensioner damper when the auto tensioner fully operates under both high ambient temperature and high load conditions. To eliminate this concern, the shape of the drive belt auto tensioner damper has been changed.”
 
:
16.5 CX-5 Tour/AWD
This’s really odd. Is there any difference on gas mileage before and after? Did you disconnect the battery while replacing the tensioner and belts? I believe you use OEM belts so you won’t have problem like minnesotaart who used shorter Dayco stretch water pump belt. IMO your Gate tensioner should not give you the problem you described. Something else happened during your belt and tensioner change.

Gas mileage seems about the same. I think I disconnected the battery but I don't recall anymore as it was a while ago. Would disconnecting the battery make a difference? Here's what I've done:

Replace/Perform:
  1. Belt Tensioner: The only non-OEM item; may affect the pedal kickdown.
  2. Water Pump Belt: Shouldn't affect the pedal kickdown
  3. Serpentine Belt: It's OEM, so it shouldn't affect the pedal kickdown and after driving 1.7k miles, it should've worn in already no matter if it's stiff or not.
  4. Belt Tensioner Nut: Shouldn't affect the pedal kickdown
  5. Belt Tensioner Bolt: Shouldn't affect the pedal kickdown
  6. Bleed air from belt tensioner: I slowly rotated the the belt tensioner and took longer than the recommended 5 seconds and performed this procedure about (3) times.
I mean I can't think of anything else aside from these variables that I touched.
 
:
16.5 CX-5 Tour/AWD
i second that, I doubt the aux belt and tensiomer change can produce this effect.
Did you disconnect the battery?

I think I did. I know that I'm careless sometimes and may accidentally activate the remote turn on switch so I'm pretty sure I did at least. What difference would disconnecting the battery make?
 

yrwei52

2016 Mazda CX-5 GT AWD w/Tech Pkg
Contributor
:
Plano, Texas, USA
Gas mileage seems about the same. I think I disconnected the battery but I don't recall anymore as it was a while ago. Would disconnecting the battery make a difference? Here's what I've done:

Replace/Perform:
  1. Belt Tensioner: The only non-OEM item; may affect the pedal kickdown.
  2. Water Pump Belt: Shouldn't affect the pedal kickdown
  3. Serpentine Belt: It's OEM, so it shouldn't affect the pedal kickdown and after driving 1.7k miles, it should've worn in already no matter if it's stiff or not.
  4. Belt Tensioner Nut: Shouldn't affect the pedal kickdown
  5. Belt Tensioner Bolt: Shouldn't affect the pedal kickdown
  6. Bleed air from belt tensioner: I slowly rotated the the belt tensioner and took longer than the recommended 5 seconds and performed this procedure about (3) times.
I mean I can't think of anything else aside from these variables that I touched.
When you disconnect the battery long enough, the ECU gets reset and the timing and other parameters get changed which could make your car feels differently from your driving habit. But you’ve driven your CX-5 for 1.7K miles, the learning should be done and the performance should have changed back to it used to be, based on your driving habit.

May be you can start using some good fuel detergent, replacing spark plugs, even cleaning up the intake manifold and valves, one step at time. In other words, belt tensioner should not be the culprit of your current “problem” and you should spend time on other items if you really want to tackle the issue.

Oh, check tire pressure too.
 
:
16.5 CX-5 Tour/AWD
When you disconnect the battery long enough, the ECU gets reset and the timing and other parameters get changed which could make your car feels differently from your driving habit. But you’ve driven your CX-5 for 1.7K miles, the learning should be done and the performance should have changed back to it used to be, based on your driving habit.

May be you can start using some good fuel detergent, replacing spark plugs, even cleaning up the intake manifold and valves, one step at time. In other words, belt tensioner should not be the culprit of your current “problem” and you should spend time on other items if you really want to tackle the issue.

Oh, check tire pressure too.
That makes sense. I'm close to the spark plug change interval, currently at 67.7k right now so around 70-75k is where I'm planning to do a swap with ruthenium spark plugs. I just think it's a little weird that after replacing it, it feels different so seeing you list out all of those different items is strange. Tire pressure is normal as I put it 4-5 PSI below maximum on a weekly/bi-weekly basis.

The only other thing that I could think of is to put the old tensioner back and see if it's any better and if not, then it may be other issues that you listed. Feeling a little lazy these days so maybe I might wait till next year lol
 

yrwei52

2016 Mazda CX-5 GT AWD w/Tech Pkg
Contributor
:
Plano, Texas, USA
Tire pressure is normal as I put it 4-5 PSI below maximum on a weekly/bi-weekly basis.
What do you mean by that? Your Touring 225/55R17 tires have 34 psi recommended although I usually put 3~4 psi higher than recommended psi.

The only other thing that I could think of is to put the old tensioner back and see if it's any better and if not, then it may be other issues that you listed. Feeling a little lazy these days so maybe I might wait till next year lol
You’d done at least 2 big items for maintenance recently and gave us so many valuable information. I’m too lazy to replace my leaky tensioner which I‘m supposed to at this time. But I do need to change the oil when I see the wrench indicator and “Oil change due” message within a month.

Honestly, get a set of NGK compatible plugs and change them. This’s worth than putting back your old tensioner back to verify time wise. Of course it’d be interesting to see the result of you putting back the old tensioner if you have the urge to do it.
 
:
16.5 CX-5 Tour/AWD
What do you mean by that? Your Touring 225/55R17 tires have 34 psi recommended although I usually put 3~4 psi higher than recommended psi.


You’d done at least 2 big items for maintenance recently and gave us so many valuable information. I’m too lazy to replace my leaky tensioner which I‘m supposed to at this time. But I do need to change the oil when I see the wrench indicator and “Oil change due” message within a month.

Honestly, get a set of NGK compatible plugs and change them. This’s worth than putting back your old tensioner back to verify time wise. Of course it’d be interesting to see the result of you putting back the old tensioner if you have the urge to do it.
I don't follow the recommended tire PSI on the driver side door. The number is typically for the factory OEM tires that came with the vehicle to maintain the best balance between fuel economy and comfort. I typically check what the maximum PSI the tire is rated for on the sidewall.

OEM Tires: GEOLANDAR G91A - SIZE: P225/65R17
These are rated for 44 PSI maximum.

Current Tires: GOODYEAR ASSURANCE WEATHERREADY - SIZE: 225/65R17
These are rated for a 51 PSI maximum.

Next set of Tires (next week): MICHELIN CROSSCLIMATE SUV - SIZE: 225/65R17
These are rated for a 50 PSI maximum.

What I mean is that, I inflate my tires to about 47 PSI typically. I did a dozen tests after driving the car at highway speeds for 2-3 hours and then used the tire gauge to see how much PSI the tires would increase up to and it's usually <3 PSI which is under the maximum PSI listed on the tire sidewall. I know that this is a heavily debated topic and if you Google around, most people follow what's listed on the driver side door but I don't because I rather have better handling and less rolling resistance which the higher PSI allows.

I've been going by this rule for the past 2 sets of tires (67.7k miles) and I've ran into no issues so far so I am sticking with what works for me but the ride is definitely stiffer for sure.

You’d done at least 2 big items for maintenance recently and gave us so many valuable information. I’m too lazy to replace my leaky tensioner which I‘m supposed to at this time. But I do need to change the oil when I see the wrench indicator and “Oil change due” message within a month.

Honestly, get a set of NGK compatible plugs and change them. This’s worth than putting back your old tensioner back to verify time wise. Of course it’d be interesting to see the result of you putting back the old tensioner if you have the urge to do it.

Yeah, I try my best to give as much information as possible so you guys can see the entire process instead of just the finished product :D. Replace it whenever you feel comfortable, there's honestly no rush. I think if you aren't experiencing any issues (e.g. noise, squealing etc.) you should be fine. Not sure if you're interested but maybe you can try an extended OCI like me and use filters/oils that can be rated up to 20k for fun hehe.

I don't know why but I just have the urge to try out out those new ruthenium plugs. They seem extremely promising. Also, I just found something very interesting as I'm sure it'll apply for most of us who use the NGK plugs. There are some people on YouTube that swear by using anti-seize and on the official NGK website, they state that there's no need for anti-seize.

5 THINGS YOU SHOULD KNOW ABOUT SPARK PLUGS

5 THINGS YOU SHOULD KNOW ABOUT SPARK PLUGS​

1. Anti-seize

NGK spark plugs feature trivalent plating. This silver or chrome-colored finish on the threads is designed to provide corrosion resistance against moisture and chemicals. The coating also acts as a release agent during spark plug removal. NGK spark plugs are installed at the factory dry, without lubrication or anti-seize.

Anti-seize can act as a lubricant, altering torque values up to 20 percent, increasing the risk of spark plug thread breakage and/or metal shell stretch. Thread breakage can sometimes involve removing the cylinder head for repair. Metal shell stretch changes the heat rating of the spark plug and can result in serious engine damage caused by pre-ignition. Do not use anti-seize or lubricant on NGK spark plugs. It is completely unnecessary and can be detrimental.

2. Corona stain

Corona stain is a light brown or tan discoloration on the outside of the ceramic insulator above the metal shell/hex. Corona stain is created by the high voltage traveling thru the plug that attracts the dirt or oil particles surrounding the exposed ceramic insulator between the wire/coil boot and spark plug metal shell. Corona stain is completely normal and should not be mistaken for exhaust gas blow-by or a broken seal inside the spark plug.

3. Gapping fine-wire spark plugs

While most NGK spark plugs are pre-gapped, there are occasions when the gap requires adjustment. Care must be taken to avoid bending or breaking off the fine-wire electrodes. NGK recommends a round wire-style or pin gauge gap tool to measure the gap. If the gap must be adjusted, use a tool that only moves the ground electrode and does not pry between or against the electrodes. NGK also recommends adjusting the gap no more than +/- 0.008” from the factory preset gap.

4. Torque

Torque is crucial in the ability of the plug to dissipate heat and perform properly. Always follow the manufacturer recommended torque specification. An under-torqued spark plug can lead to excessive vibration and improper heat dissipation, causing spark plug and/or engine damage. Over torquing may cause any of the following: thread damage/breakage, compromised internal seals leading to gas leakage, metal shell stretch leading to poor heat dissipation and pre-ignition.

5.“Copper spark plugs”

“Copper spark plugs” is a term often used to describe a standard material spark plug. However, this terminology is incorrect, as standard material plugs do not have electrodes made from copper. Copper is soft with a low melting point and cannot be used for electrodes, as they would wear very quickly. A standard material spark plug uses a nickel-alloy that may include a small copper core. The copper core has nothing to do with the electrical performance of the spark plug. A copper core is used to increase heat dissipation and durability by lowering the electrode temperatures. Nearly all NGK spark plugs, including precious metal iridium and platinum plugs, have a copper core to increase the electrode durability. Special nickel alloys, platinum, and iridium electrodes, along with copper cores are all used to enhance durability – durability meaning how long a spark plug will last before it needs to be replaced.

NGK Ruthenium HX Spark Plug Part # 92274
Product Features:

  • NGK RUTHENIUM HX spark plugs provide unparalleled durability and a more complete fuel burn resulting in a quicker throttle response, smoother idle and better cold starts. Trivalent metal plating eliminates need for anti-seize.
I'm honestly a little fed up with the new belt tensioner and I'm willing to swap it back but easier said than done since I'll need to jack up the car again and I'm not going to do that until maybe next week when I lubricate the brakes after getting the new set of Michelin tires mounted hehe
 
Last edited:
Top