Honda Odyssey Forum banner

1 - 20 of 39 Posts

·
Registered
Joined
·
10,959 Posts
Discussion Starter #1
Hey, thought I'd post a solution I found to something that has been plaguing me for quite some time.

This is on my own 2008 Odyssey Touring, J35A7 VCM engine with hydraulic serpentine belt tensioner. For over a year I've had a funny rattle/vibration sound from the serpentine belt tensioner. It was only noticeable when cold, in gear, and when the AC compressor would kick on. In Park it wasn't as noticeable. I could go under the hood and put a long screwdriver on the tensioner bolt and feel the vibration. I don't recall exactly when it first happened but I remember the first thing I did was replace the tensioner as it had around 180K or something at that time so figured it was worn out and time for a new one. I was shocked when a new genuine Honda tensioner it didn't fix it. Since it only happened with the AC on I then figured it must be some extra vibration caused by an aging AC compressor and I wasn't going to bother with it. However, at around 203K the AC quit working.

I found a leak in the condenser and decided that with such high mileage it was time to rebuild the AC system. I replaced the AC compressor, condenser, and both expansion valves. When that was all done, the AC worked great (and still does) but that same vibration and rattle sound was still there when cold. While a visual inspection of the harnonic balancer showed no issues I decided to replace the harmonic balancer anyway since I was placing an order from Bernardi for some other parts. They are prone to failure on these engines and with the 218K that is currently on it thought maybe it wasn't lined up or somehow was causing the issue. I installed that last week. Nope. Didn't fix it.

After scouring the Internet and finding nothing at all about vibrations/rattles on the belt drive attributed to anything other than a bad tensioner I decided the only thing left was the belt itself. I'd replaced it at timing belt time at around 180K with a Bando belt but it had been making that noise prior. I don't recall what belt was on it before--probably a Dayco from Advance Auto. I've since learned Dayco belts aren't very good so I went with the Bando that time. I've installed many of them over the last couple of years and never had any issues or come backs with them. However, being at my wits end with this I decided to run to the local Honda dealer and buy a genuine Honda belt (supposedly made by Mitsuboshi.) When I brought it home and compared it to my Bando belt that still looked fairly new I was shocked. I've never compared two new (or lightly worn) belts before. I've compared a new Bando with a worn OEM and never noticed too much issue. However, below is what I found.

The Bando belt isn't that old and still has lots of life in it as is apparent by the the labeling still looking fresh. My special tool for measuring the grooves (not shown) showed it to be in great shape with very little wear on the groove side. Using a caliper I measured the thickness of both belts:

Bando: 4.38mm

153589



Honda belt: 5.09mm

153590



As shown above, the Bando belt is nearly 0.7mm thinner than the OEM Honda belt. That's nearly 20% thinner than the OEM belt. When you hold both at the same time there is a huge difference in the feel of the belts. The Honda belt is thick and rigid while the Bando belt felt thin and wimpy.

I installed the Honda belt and started it up. No more vibrations! I thought, well, I need to do a cold start so I waited until this morning and started it up again. Noise is gone.

Lesson learned: I've heard good things about Bando belts and have never had any issue with them. Their <$10 cost on RockAuto and Amazon makes them a good option when compared to the $53 price tag (discounted from the $64 the parts guy wanted at first) that Honda charges. However, the results speak for themselves. I bought the Bando belt on Amazon so maybe there are fake Bando belts too. All I know is a cheap belt fit nicely and never squealed but caused me much headache.

As to why the thinner belt caused the tensioner to vibrate, I'm not sure. All I can think of is it tends to slap around a bit more than the thicker, heavier belt. It does go directly from the AC compressor to the tensioner so maybe there is a weird vibration there that causes the belt to slap a bit and vibrate the tensioner. For now I'm not able to duplicate the vibration and rattle anymore when cold so I'm happy. Just thought I'd share with everyone else since I've found nothing about anything like this anywhere on the Internet.
 

·
Registered
Joined
·
438 Posts
I'll update once I measure and verify, but I believe the Continental belt on Rockauto is a similar thickness to the Honda belt, at least the one I bought for my Accord seemed to be. I haven't noticed any sound on mine in the last 3k miles

Sent from my ONEPLUS A5000 using Tapatalk
 

·
Registered
Joined
·
957 Posts
Amazing John. Just goes to show you if it attaches to the motor, use the OEM part. Nearly every time I’ve veered from this advice it usually ends poorly. I’ll keep my eye on the replacements.


Sent from my iPad using Tapatalk
 

·
Registered
Joined
·
518 Posts
Good info..

I used the OEM when changing the tensioner. It was making noise. Changed tensioner and belt. No more noise.

Did anyone compared the Aisin Timing belt with OEM?

It could be the fact that the belt was fake.
 

·
Registered
Joined
·
288 Posts
Excellent observation and post John. Thank you for the details and sharing!

Just when we're tempted to use other replacement parts options, this is almost a continous reminder of the problem of counterfeit goods on Amazon and inferior sourcing/manufacturing processes used by otherwise reputable brands.

Would you consider adding this post to the Gen II forum?

Sent from my SM-N910V using Tapatalk
 

·
Registered
Joined
·
518 Posts
Thanks for sharing John. Good thing when I did my TB about a year ago and ended up using OEM belt.
 

·
Registered
Joined
·
7,361 Posts
As to why the thinner belt caused the tensioner to vibrate, I'm not sure. All I can think of is it tends to slap around a bit more than the thicker, heavier belt. It does go directly from the AC compressor to the tensioner so maybe there is a weird vibration there that causes the belt to slap a bit and vibrate the tensioner. For now I'm not able to duplicate the vibration and rattle anymore when cold so I'm happy. Just thought I'd share with everyone else since I've found nothing about anything like this anywhere on the Internet.
Sir John, I would tend to agree with your professional assessment that the different belt mass might truly make the difference in terms of harmonics (or damping it).

I've heard of this problem before (new belt, new noises), but never read of a solution until today.

OF
 

·
Registered
Joined
·
438 Posts
Sir John, I would tend to agree with your professional assessment that the different belt mass might truly make the difference in terms of harmonics (or damping it).

I've heard of this problem before (new belt, new noises), but never read of a solution until today.

OF
It's definitely a mass issue, when you look at the vibration of the individual belt drive components, the mass on the belt itself acts as a damper on the system. The tensioner is designed to be used with the mass of the OEM belt. So when a thinner belt is used, it makes sense that when a thinner and lighter belt is used, that it would vibrate a bit more because the belt is no longer as effective in dampening the vibration

Sent from my ONEPLUS A5000 using Tapatalk
 

·
Registered
Joined
·
288 Posts
Sir John, I would tend to agree with your professional assessment that the different belt mass might truly make the difference in terms of harmonics (or damping it).

I've heard of this problem before (new belt, new noises), but never read of a solution until today.

OF
(Hi OF!)

To add to your point of mass impacting harmonics, I was looking at a really durable stainless steel idler wheel to replace the stock aluminum wheel on our '03. I would believe the stainless material wouldn't wear as the aluminum does and have a much more durable bearing (the idler wheel is from a Cummings engine where service life is measured by a lot longer frequency).

The stainless idler wheel is heavier (I haven't weighed it), so I wonder if that would impact the harmonics using the stock tensioner as the thinner/lighter belt affected JC?

Sent from my SM-N910V using Tapatalk
 

·
Registered
Joined
·
7,361 Posts
Man, I have zero idea if it would be helpful or hurtful.

I'm just truly amazed you found that item and it fits! This is especially considering that it is from a vastly different company. I mean, if you'd said, "Hey, I found this part on the Acurazine forums, and it's a drop-in replacement for the one on our Odyssey..." I'd be impressed. You found a part from a Cummins diesel! :geek:

OF
 

·
Registered
Joined
·
438 Posts
(Hi OF!)

To add to your point of mass impacting harmonics, I was looking at a really durable stainless steel idler wheel to replace the stock aluminum wheel on our '03. I would believe the stainless material wouldn't wear as the aluminum does and have a much more durable bearing (the idler wheel is from a Cummings engine where service life is measured by a lot longer frequency).

The stainless idler wheel is heavier (I haven't weighed it), so I wonder if that would impact the harmonics using the stock tensioner as the thinner/lighter belt affected JC?

Sent from my SM-N910V using Tapatalk
While it would be more durable, you have to consider the mass difference as well as the mass distribution, the additional rotational inertia could cause the bolt to shear off because it's designed for an aluminum part which is lighter. Also, you may notice more vibration because the steel part is no longer balanced with other parts of the system. Lastly, steel tends to become brittle at lower temperatures and aluminum does not, so take that into consideration if you're in an area where it gets below 10°F as that is close to the ductile to brittle transition of steel.

That being said, I too am pretty impressed that you found a Cummins part that fits. I never would have even considered that it fits

Sent from my ONEPLUS A5000 using Tapatalk
 

·
Registered
Joined
·
77 Posts
Great info! I’ve used 2 Napa belts now and had no issues. I believe they are made by Gates Rubber. If I have issues I’ll know to go to OEM. Thanks for the info again.
 

·
Registered
Joined
·
254 Posts
FWIW my previous vehicle was a honda passport (isuzu rodeo) whose 3.2 v6 used 3 accy' drive belts. The alternator/fan/crank belt is serpentine with tension adjust via alternator position. After installing a high output alternator I had major headaches with belt slippage, once they slipped at all it got worse quick as the belts glazed.
I tried every belt on the market, cost wasnt much of a factor relating to grip.
The Dayco premium belt with the W profile was the only belt that worked, the first one I put on lasted until I sold the vehicle.
I know this has little relevance to the issue John was experiencing but since he mentioned Dayco I thought I would put a testimonial in for them.
I might add that both serpentine pully bearings are easily serviceable with a grease gun and needle fitting, carefully inserting the needle next to the seal.
When I did my timing belt I noticed one bearing felt dry but otherwise turned smoothly. Greasing it surely saved premature failure.
 

·
Registered
Joined
·
254 Posts
Great info! I’ve used 2 Napa belts now and had no issues. I believe they are made by Gates Rubber. If I have issues I’ll know to go to OEM. Thanks for the info again.
Yeah napa uses gates on both regular and premium lines. They are made in mexico now and didnt last me longer than other brands. The premium uses a higher grade of rubber.
FWIW if I have to buy parts from a local retailer Napa usually has the best quality, Autozone by far the worst, Oreillys a bit better but overpriced.
 

·
Registered
Joined
·
254 Posts
Excellent observation and post John. Thank you for the details and sharing!

Just when we're tempted to use other replacement parts options, this is almost a continous reminder of the problem of counterfeit goods on Amazon and inferior sourcing/manufacturing processes used by otherwise reputable brands.

Would you consider adding this post to the Gen II forum?

Sent from my SM-N910V using Tapatalk
Im not sure counterfeiting is always whats going on. Note that the oft recommended tk002 timing belt kit has a genuine aisin water pump, and OEM is aisin, but I and many others have noticed that the casting isnt as well finished as the one that it replaces. Unknown how that affects durability.
In this case does merely picking a mitsuboshi belt off ebay or amazon, assuming its genuine, mean we get the same belt as purchased at a honda dealer?
Maybe not. Most manufacturers have different quality level lines, and sellers may market it as OEM equivilent when its only the mfr. thats the same.
 

·
Registered
Joined
·
52 Posts
It's been about 100 years since the Tacoma Narrows Bridge Collapse due to harmonic wind loading. It has taken nearly that long to develop the physics of how it happened and develop simplified calculations to model it on a computer. That failure didn't involve multiple rotating elements strung together with a flexible band that changes direction and speed. Rotational harmonic problems are extremely difficult to solve..... by other than experience and brute force methods.

My guess is that vibration showed during the initial shakedown of the engine prototype or during early production. It had enough deleterious effect that somebody stumbled onto (or possibly knew of) a solution to change the belt thickness and therefore change the harmonics of the system. It works and Honda changes the specifications for the belt to reflect. But, doesn't tell the belt manufacturers why the belt needs to be about 1 mm thicker. I am very confidant Honda chose the cheapest and easiest solution to the problem. To confirm one would need to interview the design team, if you can find any without a gag order or contracted silence or alive still.

Thanks for sharing the experience John. Every time my back hurts I forget that experience come in handy occasionally.
 
1 - 20 of 39 Posts
Top