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

minnesottaart,
While at your mechanic ask him to look at the crank pulley as well.
May be its normal but it kind of seems to have some cracks in early stages. Primarily the rubber part in between outer and inner of it
 
Might be a dumb question but is anyone planning to wait until they hear a squealing noise before replacing both the tensioner and serpentine belt? I figure if it goes bad then it goes bad but I'll have the new parts ready for it. I would like to maximize the amount of life on the old/new tensioner so I don't need to do it again for maybe the next 75-100k miles. I mean there's a possibility that Mazda could release another revision again as well....
 
OK, I'm a failure! I did NOT replace the belt tensioner or belts today. I got all ready to decided to due the "take-off-the-right-front-tire-and-splash-shield" method. I did that and unfortunately, unlike the Mazda3 in the video, the belt tensioner in the CX-5 is in an almost impossible position. I gave it a shot but I couldn't even release the tension to remove the serpentine belt. So I closed it all up and I'll bring it (and all the parts) to my favorite mechanic and let him have all the fun! To be fair, this is "probably" DIY doable if you have a lift since the working position would be much better, but I don't have a lift.

This is a picture of my dirty tensioner. Leaking? Beats me, but it makes no noise.
View attachment 227551

And after removing the tire and the splash shield, here is the view. Lots of metal in the way of where you need to get too. Tried both from this angle and the top before I gave up. Can't imagine that the standard shop time for the swap is .4 hours of labor!
View attachment 227552

I was wondering if you had a chance to watch Felix Dans video on the removal process? It looks like he was able to access the pulley upon removing the wheel splash shield but he had to use an extension

 
minnesottaart,
While at your mechanic ask him to look at the crank pulley as well.
May be its normal but it kind of seems to have some cracks in early stages. Primarily the rubber part in between outer and inner of it

Would you be able to share some pictures? I just want to get an idea of the cracks that you are referring to see if I would have the same issue upon inspection. Also, the crankshaft pulley seems like an expensive item (roughly $125).

The whole process is going to be about $253 give or take if the crankshaft pulley needs to be replaced as well.

$125 (Crankshaft Pulley) + $100 (Belt Tensioner) + $28 (OEM Serpentine Belt).

Questions:
  1. Would it be advised to replace the water pump belt as well or is that something that can be left alone?
  2. Would it be recommended to replace the mounting hardware as well? (See below in red)
1601946117323.png
 
zoom in on the last picture on page 6 and you could see the micro cracks.
its still early stage from what I could see on the pics.
 
OK, I'm a failure! I did NOT replace the belt tensioner or belts today. I got all ready to decided to due the "take-off-the-right-front-tire-and-splash-shield" method. I did that and unfortunately, unlike the Mazda3 in the video, the belt tensioner in the CX-5 is in an almost impossible position. I gave it a shot but I couldn't even release the tension to remove the serpentine belt. So I closed it all up and I'll bring it (and all the parts) to my favorite mechanic and let him have all the fun! To be fair, this is "probably" DIY doable if you have a lift since the working position would be much better, but I don't have a lift.

This is a picture of my dirty tensioner. Leaking? Beats me, but it makes no noise.
View attachment 227551

And after removing the tire and the splash shield, here is the view. Lots of metal in the way of where you need to get too. Tried both from this angle and the top before I gave up. Can't imagine that the standard shop time for the swap is .4 hours of labor!
View attachment 227552


Not a failure lol. You need the right long reach wrenches for leverage or be pretty strong. I purchased a long reach 17mm wrench as shown a couple posts back. For anyone wanting to remove the tensioner just get a kit that contains both the 17mm and 12mm wrenches. And not just long reach but Extra long reach.

Something like this https://www.amazon.com/dp/ (commissions earned)
 
Interesting. Your package has part number PET2-15-980, but the tensioner itself says the part number is “PE03-15980 K0255” (PE03-15-980) with serial number “F-569897.10” ⋯

View attachment 227536

Clarification:

The actual Piston section and facing engine bay says F-569897.07-0100 with date 12/18/2018 but bottom half with roller and facing engine says F-569897.10 with date 12/20/2018.

Must've been assembled in different areas of the plant an on different days to be bolted together.

Another case of a ULT? :) Unidentified Leaking Tensioner
 
Not a failure lol. You need the right long reach wrenches for leverage or be pretty strong. I purchased a long reach 17mm wrench as shown a couple posts back. For anyone wanting to remove the tensioner just get a kit that contains both the 17mm and 12mm wrenches. And not just long reach but Extra long reach.

Something like this https://www.amazon.com/dp/ (commissions earned)

Any chance we can use a breaker bar/socket in there or is there not enough clearance?

FYI, HF sells the long reach metric wrenches for $24.99 if anyone wants to save money :D

Metric Long Handle Combination Wrench Set, 11 Pc.

Sizes: 10mm, 11mm, 12mm, 14mm, 15mm, 17mm, 19mm, 21mm, 22mm, 24mm, 26mm
 
Any chance we can use a breaker bar/socket in there or is there not enough clearance?

FYI, HF sells the long reach metric wrenches for $24.99 if anyone wants to save money :D

Metric Long Handle Combination Wrench Set, 11 Pc.

Sizes: 10mm, 11mm, 12mm, 14mm, 15mm, 17mm, 19mm, 21mm, 22mm, 24mm, 26mm

The tensioner is right up against the engine bay. Space is really tight. You'll need wrenches with a box end.

The HF long reach metric wrenches............trust me you want to go longer. HF's long reach 17mm wrench is 12 inches whereas my extra long one is 16 inches. You could join two wrenches together but with the tight space I prefer the specialty extra long reach wrenches. That said the HF 12mm long wrench is 9 inches is actually not bad. I don't have the strongest arms therefore I'm looking for a 12mm wench at least 1 foot for more leverage.

Here's the 12mm one I'm thinking of getting: https://www.ebay.com (commissions earned) to remove the bolts.

Here's the 17mm I currently have. Perfect for releasing Tensioner tension: https://www.amazon.com/dp/ (commissions earned)

Edit: the reason why Mazda techs and mechanics can get away with using standard sized wrenches- Its because they have the car lifted up. They merely use their body weight and pull/push from below the car. For us DIY's were crouched down inside a wheel well having to use forearm strength. Not fun :(
 
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The tensioner is right up against the engine bay. Space is really tight. You'll need wrenches with a box end.

The HF long reach metric wrenches............trust me you want to go longer. HF's long reach 17mm wrench is 12 inches whereas my extra long one is 16 inches. You could join two wrenches together but with the tight space I prefer the specialty extra long reach wrenches. That said the HF 12mm long wrench is 9 inches is actually not bad. I don't have the strongest arms therefore I'm looking for a 12mm wench at least 1 foot for more leverage.

Here's the 12mm one I'm thinking of getting: https://www.ebay.com (commissions earned) to remove the bolts.

Here's the 17mm I currently have. Perfect for releasing Tensioner tension: https://www.amazon.com/dp/ (commissions earned)

Edit: the reason why Mazda techs and mechanics can get away with using standard sized wrenches- Its because they have the car lifted up. They merely use their body weight and pull/push from below the car. For us DIY's were crouched down inside a wheel well having to use forearm strength. Not fun :(
By looking at the illustration from FSM, it seems an offset box wrench is needed. How do you use 17mm extra-long wrench without offset to turn the cast hexagon and loose the belt without interfere by the crankshaft pulley from the bottom side? And how do you use no-offset 12mm extra-long wrench to loose the bolts on tensioner which are recessed inside?

Mazda FSM dose say bleeding the air of the belt tensioner is required after the installation. No mention about the torque value of the tensioner bolts, or if new bolts are needed.

Drive Belt Auto Tensioner Installation Note

CAUTION:
To allow the drive belt auto tensioner to function correctly, always bleed the air from the drive belt auto tensioner using the following procedure after assembling the drive belt auto tensioner.

1. Install the drive belt auto tensioner to the engine.

CAUTION:
• To prevent damage to the drive belt auto tensioner, do not apply excessive torque after the tensioner moves full-stroke.

2. Insert the wrench into the cast hexagon on the drive belt auto tensioner, move the drive belt auto tensioner up and down at full-stroke three times to bleed the air.

NOTE:
• By moving the drive belt auto tensioner up and down full-stroke three times, the piston inside the tensioner moves to bleed the air.
 
By looking at the illustration from FSM, it seems an offset box wrench is needed. How do you use 17mm extra-long wrench without offset to turn the cast hexagon and loose the belt without interfere by the crankshaft pulley from the bottom side? And how do you use no-offset 12mm extra-long wrench to loose the bolts on tensioner which are recessed inside?

Mazda FSM dose say bleeding the air of the belt tensioner is required after the installation. No mention about the torque value of the tensioner bolts, or if new bolts are needed.

Looks like the nut/bolts are 17-22 lb ft. To answer my previous question about the bolts, I would maybe assume that the hardware doesn't need to be replaced unless there's rust.

1601987939125.png
 
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For anyone who can answer, I have a few questions about bleeding the air from the belt tensioner:

Move the drive belt auto tensioner up and down at full-stroke three times to bleed the air.


Questions:
  1. Does this mean turn it in a circle or just all the way upward/downwards? I'm confused because it says up and down and then full stroke.
  2. Does it matter which direction I turn the cast-hexagon (counter clockwise/clockwise)?
  3. How do I know if I have completed a "full-stroke"? Will I feel a point where I can't go any further? The manual doesn't really specify aside from "do not apply excessive torque".
  4. Can this be bled off the vehicle?
  5. Does this have to be done with/without the new serpentine belt installed?
  6. What happens if I release the "cast hexagon" mid-way, will the belt tensioner become damaged?
  7. What happens if I don't bleed it correctly or don't bleed it at all?
  8. How do I know if it's bled correctly?
Here's some replies that I've received from another forum. Hopefully it helps anyone trying to perform this procedure:
1601992739574.png


1601992748439.png


1601992837400.png
 
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The wrench I tried to use is 18" long. It has a ratcheting, swivel head with a splined profile insert. The ratchet "catches" after just 4 degrees of movement. https://www.amazon.com/dp/ (commissions earned)

From the top, I managed to engage the 17mm tension relief hex thing from the top, but there wasn't enough freedom of movement to ratchet even once. I couldn't budge the tension relief at all. Hooked it from the side through the wheel well and again couldn't budge it. I must be too weak. I do think it would be easy enough if it was on a lift. I'm retired and I have enough money, so I'm OK hiring a younger guy to do what I can no longer do! :D
 
By looking at the illustration from FSM, it seems an offset box wrench is needed. How do you use 17mm extra-long wrench without offset to turn the cast hexagon and loose the belt without interfere by the crankshaft pulley from the bottom side? And how do you use no-offset 12mm extra-long wrench to loose the bolts on tensioner which are recessed inside?

Mazda FSM dose say bleeding the air of the belt tensioner is required after the installation. No mention about the torque value of the tensioner bolts, or if new bolts are needed.


Pause to 7:00 mark of this video tensioner. Image that but closer to engine bay since vid shows a 2.0 liter engine.

Tensioner bolt: My extra long wrench has a 15 degree offset but what really helps is being boxed in the end. The boxed end helps extend grip sideways (90 degrees) to capture the Tensioner.

On Bolts you can get away with 0 offset:
Bottom Bolt- it sticks out more (whereas the tensioner bolt is more recessed) so even a 0 offset with boxed end can grab it. Again look at 7:00 to compare the 2.

Top Bolt: Good news! There's nothing in your way. Leverage would be nice though. Its the other two that are the issue.

Minnesotaart: You start not with a shove but more of a constant push. Don't worry if it doesn't move at first just apply a constant push for like 5 seconds. It feels like pushing into a brick wall I know!!! Then all of a sudden it starts to give up slowly but surely allowing you to go counterclockwise. I agree a lift is better.....if I had the money.

Edit: Was at Harbor freight today and saw the metric Long wrenches in person finally. They keep selling out.....hey they may actually work.

Edit#2 I just right now successfully removed/replaced the top tensioner bolt from then engine bay using a 12mm ratcheting wrench from this Harbor Freight Kit 12mm ratchet
 
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Pause to 7:00 mark of this video tensioner. Image that but closer to engine bay since vid shows a 2.0 liter engine.

Tensioner bolt: My extra long wrench has a 15 degree offset but what really helps is being boxed in the end. The boxed end helps extend grip sideways (90 degrees) to capture the Tensioner.

On Bolts you can get away with 0 offset:
Bottom Bolt- it sticks out more (whereas the tensioner bolt is more recessed) so even a 0 offset with boxed end can grab it. Again look at 7:00 to compare the 2.

Top Bolt: Good news! There's nothing in your way. Leverage would be nice though. Its the other two that are the issue.

Minnesotaart: You start not with a shove but more of a constant push. Don't worry if it doesn't move at first just apply a constant push for like 5 seconds. It feels like pushing into a brick wall I know!!! Then all of a sudden it starts to give up slowly but surely allowing you to go counterclockwise. I agree a lift is better.....if I had the money.

Edit: Was at Harbor freight today and saw the metric Long wrenches in person finally. They keep selling out.....hey they may actually work.

Thanks for the video. At about 15:20, he has a serpentine belt tool and I found it on Harbor Freight. Looks like there's no need for a offset box wrench if that's the case since the tool is slim enough to fit in the crevices. Maybe the only issue that we'll run into is torqueing it down.

Serpentine Belt Tool Kit

1602013112558.png
 
Thanks for the video. At about 15:20, he has a serpentine belt tool and I found it on Harbor Freight. Looks like there's no need for a offset box wrench if that's the case since the tool is slim enough to fit in the crevices. Maybe the only issue that we'll run into is torqueing it down.

Serpentine Belt Tool Kit

View attachment 227603

See my edit of my previous post.

Tensioner Bolt - Needs a wrench, socket will not fit.
bottom bolt- Needs a wrench, socket will not fit. Recommend a ratchet wrench.
top bolt - Regular sized ratcheting wrench from engine bay access works-confirmed. Socket might work from wheel well access.

New Recommendation: 1 extra long 17mm wrench with 15 degree offset and boxed end. A set of ratcheting wrenches.
 
Thanks for the video. At about 15:20, he has a serpentine belt tool and I found it on Harbor Freight. Looks like there's no need for a offset box wrench if that's the case since the tool is slim enough to fit in the crevices. Maybe the only issue that we'll run into is torqueing it down.

Serpentine Belt Tool Kit

View attachment 227603
Look at a bunch of those online and the common complaint was they broke. Twisted the square socket head right off the body of the tool.
 
Look at a bunch of those online and the common complaint was they broke. Twisted the square socket head right off the body of the tool.

I went through a few of these wrenches on Amazon/Lowes/Home Depot and they had mostly positive reviews, same with HF with the last 1 star review from 2019. I wouldn't read too much into it honestly, there's going to be bad reviews about everything online. Anyways, my plan was to use a flare nut crow foot to see if it'll even fit in the tight space. I'm thinking it will fit so I don't need to buy any more tools but we'll see.

The biggest issue I have with the offset/box wrenches is that it's going to round/strip the bolt head and if that happens, it'll be a huge PITA to remove/extract the bolt and I won't run into that issue with a socket or a flare nut crow foot. Difference is that the box wrenches are 12 point vs a flare nut/6 point wrench having less of a gap

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