Yamada water pumps
- Thread starter rcs
- Start date
Yes that is why I am going to the dealership this week.
I am not looking for anyone here to resolve a dispute. My original question is regarding the Yamada water pumps and if anyone has ever had any issues with them As compared to the Aisin ones.
MolaKule
Staff member
Let us know what the dealership has to say of this noise.
Yes I will. Thank you for your time.
There are zero issues with using the OEM Yamada water pump along with the Gates Unitta timing belt. The Unitta belt is made in Japan by Gates to a higher standard than the U.S. made Gates timing belts. These are the Honda OEM factory parts used by Honda dealerships with 100% success. AISIN made water pumps for Honda vehicles in the 80's and 90's and most Toyotas, but Yamada is the OEM supplier for the Honda V-6 engines. Mitsuboshi belts are OEM for many japanese vehicles, including many older Hondas. The problem with the AISIN water pump is that the casting is slightly off by a few degrees on the mounting boss for the idler pulley, causing the belt to ride at a slight angle which can cause the warbling noise due to the timing belt occasionally rubbing on the pulser flange. There is a shim that Honda makes for ~$25 to correct the angle of the idler pulley when using AISIN pumps on the J35 V-6 engines. The official technical service bulletin describes the resolution procedure here:
HONDA TSB #08-045
HONDA TSB #08-045
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Thanks so much Nukeman! So I guess I have to either put in an OEM Yamada pump and bet or have them do the shim? How much work is it to put in the shim? I assume they have to tear everything apart to do it?
I did read the bulletin,...and mine is not a chirp noise it is rubbing rhythmic noise. My Honda is Pilot 2015,...does this still apply?
Also with all of the above being said, folks with more knowledge than myself say the pump still works it is just the noise that is the nuisance. But when I think about this, if the belt is rubbing on the pulser flange wouldn't the belt eventually become harmed by this causing engine failure?
This issue is tied to the AISIN water pump, so it does apply for your 2015 Pilot since that is what your mechanic installed. While the timing belt does slightly rub the flange, most reports appear to indicate that the contact is minor and the belt does not seem to be compromised. However, I would not be tolerant of the annoying chirping sound. In addition, the J35 engine is an interference engine so a broken timing belt could cause severe engine damage. I suggest you take the TSB to your mechanic and to a Honda dealership to see what they are willing to do and what the cost would be. Installing the shim and grinding the flange is probably 75% of the labor of replacing the water pump with a Yamada, but would save you the cost of the new pump and Unitta timing belt.
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Thanks so much Nukeman7 for that great explanation. Is it possible just to put in a new water pump and keep the same Mitsuboshi timing belt, tensioner and pulleys? Or do they have to go in as a set? Who or where are the OEM tensioners made, I have read where they have failed?
My only concern with them grinding the flange is if they don't do it right, and I have a worse problem.
I appreciate your time in helping me with this.
I would not install the Yamada pump without also installing the Unitta belt since the part is only ~$100 retail. No additional labor charges required since the belt must be removed to access the water pump. Reusing the tensioner assembly and idler pulley would be fine if they are Koyo units. The AISIN kits normally come with Koyo pulleys which are Honda OEM. As your original post indicated, the AISIN kit is excellent except for the issue with the water pump mounting flange being off-angle. If you are going to have the same mechanic do the work, see if you can purchase the Yamada & Unitta parts from an online Honda Dealership parts source which offer substantial discounts. Don't buy them from a non-Honda dealership due to the potential for counterfeits. I order online from Checkered Flag Honda to get the discounted price and drive 20 minutes away to pick it up the same day to save on shipping. Your local Honda dealer might have an online sales website or price match other sites w/shipping added.
Checkered Flag Honda Yamada Water Pump
Checkered Flag Honda Unitta Timing Belt
Also, in my opinion, it is too early to do the TB service at 49,000 miles even if it is 7 years old. I have replaced 12 year old Unitta belts with 125,000 miles that looked to be in acceptable condition. However, caveat emptor since YMMV.
Checkered Flag Honda Yamada Water Pump
Checkered Flag Honda Unitta Timing Belt
Also, in my opinion, it is too early to do the TB service at 49,000 miles even if it is 7 years old. I have replaced 12 year old Unitta belts with 125,000 miles that looked to be in acceptable condition. However, caveat emptor since YMMV.
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Thank you, How is it better? Opinion or fact? Like to know. Took TB off my Accord, and I think it was mitsuboshi from factory. The tensioner is the weak link.The water pump is driven by the timing belt, so you have to remove the TB
The OEM Unitta belt is better, but there is nothing wrong with the Mitsuboshi belt you have in the Aisin kit
I think OP is worried about nothing. Aisin makes very good parts and that noise means nothing functionally, IMO. Regarding replacing at 49K even if its 7 yo, two local honda dealers told me they just look at miles, not time for TB service
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Oh yes, it is loud enough to record, and I have recorded it. But I don't know how to upload that to the website, but I could try later on.
That TSB applies to V-6 up to 2010. Hers is a 2015. Applicable?
Yes, the AISIN TKH-002 Timing Belt kit is applicable for nearly all J35 motors, including those used in all 2015 Pilots and Odysseys.
Thanks again Nukeman7. Can you tell me why the UNitta belt has to be installed also with the Yamada water pump?
I am not questioning your expertise this is for my education. I am not concerned about the $100. I was told by another member the Mitsuboshi belt was thicker and thus better. Yes all of the pulleys were Koyo The tensioner was Aisin. I would only purchase these from my dealership IF I am going to have my independent mechanic do this work. I am not sure I am going to do that. I may just have the dealership do it because of their warranty policy being better, despite the fact that they are farther away from me. My mechainc does do an excellent job at the timing belt though.
The reason why I did it so early, was because of the Honda recommendation of the 7 years. That really scared me as I have read this on the forums, better to be safe than sorry and ruin my engine. I agree in hindsight I should just left it alone. Thanks for the links.
Thanks Wilbur. I have been told to just live with the noise, but it is truly annoying. It sounds like my engine is sucking air, to me as a women it is scary not just annoying. Which is why I just don't want to let it go and do nothing, it can't be a good thing.
I wish I would have had someone tell me that it is the miles that count and not the years. I drive this car only short distances, work, grocery store and to church.
This has been a nightmare to say the least!
I have been told the Mitsuboshi belt is thicker and that is a good thing,...but have also been told that it could be the cause for the noise?
As you guys can see I am being told many things and pulled from all sides. I don't have anyone to give me any guidance. Thank you all who have responded and are helping me with this issue.
Correct. The warbling sound is common on the aftermarket Aisin pumps. It has to do with how the tensioner pulley mounts. The noise is generally harmless.
If the noise bothers you, then you will need to replace with a Genuine Honda pump. The Mitsuboshi belts included in the kits are also not as "robust" than the Genuine belt, so it is also possible for there to be a slight difference in belt tensioner that could cause noise.
In summary, don't worry about it.
I have read at least one entry in the Odyssey forum where the individual had a bit of slack in the tensioner using the Mitsuboshi belt with the Yamada pump. He resolved it by installing the Unitta belt and suggested the Mitsuboshi was ever so slightly longer. I have used Mitsuboshi timing belts on 4 cylinder Hondas with perfect results, but the Honda V-6's seem to be more particular. In my opinion, the Japanese made Unitta timing belt is higher quality than the Thailand made Mitsuboshi belt for the J35 motor, regardless of actual or perceived thickness. I have NEVER heard of a Yamada / Unitta combo installation that has caused any noise, unlike the AISIN / Mitsuboshi combo. There is too much labor involved to potentially save ~$100 by reusing the Mitsuboshi belt.
