Serpentine belt confusion YD25DDTi

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Heyman
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Serpentine belt confusion YD25DDTi

Postby Heyman » Mon Mar 27, 2023 3:05 am

Hi was looking to change my serpentine belt

Have 90k on clock it squeaks when damp or cold, looks ok.

But belt on the engine is totally different to the manual

I have an 2006 pathfinder adventura 2.5 diesel YD25DDTi

The manual shows one big belt but I have 2 any guides to how to change them both? As I take it self tensioning?

https://postimg.cc/gallery/2ftjdV5
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VStar650CL
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Re: Serpentine belt confusion YD25DDTi

Postby VStar650CL » Mon Mar 27, 2023 5:16 am

We don't have the diesels here in the 'States, but if the metric PK numbers on the belts are legible, this is how to read them:
https://assets.gates.com/content/dam/ga ... 001-16.pdf

This Dayco reference is also useful, practically everyone in the belt business xrefs to Dayco:
https://www.daycoaftermarket.com/wp-con ... _GUIDE.pdf

Heyman
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Re: Serpentine belt confusion YD25DDTi

Postby Heyman » Mon Mar 27, 2023 5:40 am

Ah cool will double check them

Main guide I was looking for is how to change them…

Thanks

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VStar650CL
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Re: Serpentine belt confusion YD25DDTi

Postby VStar650CL » Mon Mar 27, 2023 5:59 am

Nissan pretty much only uses two types of tensioners, manual with a right-angled tension bolt and locknut, or auto with a spring-loaded tensioner. The auto tensioners are just rotated with a wrench (usually 14mm) to relieve the belt. On most of the 4-cyl's you have to get at the tensioner from the wheel well, they're inaccessible from on top. If the A/C Compressor is located on the big belt, that's usually the place to take loose first and slide back on last. Sliding the belt over the crank pulley won't work on most models. If the routing is complicated and you don't have the proper diagram, sketching one before removal is a good idea.

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VStar650CL
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Re: Serpentine belt confusion YD25DDTi

Postby VStar650CL » Mon Mar 27, 2023 6:03 am

PS - This looks to be the manual tensioner for your small belt:

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Heyman
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Re: Serpentine belt confusion YD25DDTi

Postby Heyman » Mon Mar 27, 2023 6:11 am

Champion! Cool will get on the case and sort it out

Appreciate the help

Thanks once again

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palmerwmd
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Re: Serpentine belt confusion YD25DDTi

Postby palmerwmd » Mon Mar 27, 2023 6:26 am

Heyman wrote:
Mon Mar 27, 2023 6:11 am
Champion! Cool will get on the case and sort it out

Appreciate the help

Thanks once again
Welcome to the NissanPath! :D

Heyman
Posts: 7
Joined: Mon Mar 27, 2023 2:40 am

Re: Serpentine belt confusion YD25DDTi

Postby Heyman » Wed Jun 21, 2023 6:03 am

Ok changed the belts was pretty easy as in loosen the bolt and release tension, changed both belts will upload diagram for this layout

Problem now is belt is squealing now and again when starting any ideas, pulleys all turn by hand (ac alternator)

Squeal lasts until over 3000 revs sometimes get a clicking sound near alternator but can’t be sure

Any ideas? I used a little deelectic grease on the groves

Heyman
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Re: Serpentine belt confusion YD25DDTi

Postby Heyman » Wed Jun 21, 2023 6:14 am

https://ibb.co/hWYRdsk

Image of belts layout

What’s the correct tension on the belts? I have a krikit guage just wanted to clarify

Heyman
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Re: Serpentine belt confusion YD25DDTi

Postby Heyman » Wed Jun 21, 2023 6:15 am

D837D0C4-40AF-4A96-9F3C-A9B2FE03CAE7.png

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AS_The_Crow_Flys
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Re: Serpentine belt confusion YD25DDTi

Postby AS_The_Crow_Flys » Thu Jun 22, 2023 11:20 pm

i would suggest trying to pinpoint the noise. you may have something worn out like a tensioner bearing.

you can use a length of hose as a redneck stethoscope. one end to you ear, the other you point at all the parts on the belt path. listen to pinpoint the squeal.

please be aware that messing around near the belts with a running engine can be dangerous and shoving a hose in the area definitely doesn't make it any safer. so try this at your own risk and be careful.

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VStar650CL
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Re: Serpentine belt confusion YD25DDTi

Postby VStar650CL » Fri Jun 23, 2023 11:43 am

For $7 one of these will serve you much better than a piece of hose, and it has a foot-long snout for sticking into places your ears and nose shouldn't go. I personally wouldn't be without one:
https://www.harborfreight.com/mechanics ... 63691.html

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AS_The_Crow_Flys
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Re: Serpentine belt confusion YD25DDTi

Postby AS_The_Crow_Flys » Fri Jun 23, 2023 12:05 pm

VStar650CL wrote:
Fri Jun 23, 2023 11:43 am
For $7 one of these will serve you much better than a piece of hose, and it has a foot-long snout for sticking into places your ears and nose shouldn't go. I personally wouldn't be without one:
https://www.harborfreight.com/mechanics ... 63691.html
lol - you don't like the hose method. The stethoscope probably works better but you can use any length of hose whereas that stethoscope not very long which requires your face to be kinda close to spinning parts and seeing as its metal could do some real damage. A hose might slap you in the face but it won't stab you.

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VStar650CL
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Re: Serpentine belt confusion YD25DDTi

Postby VStar650CL » Fri Jun 23, 2023 12:34 pm

AS_The_Crow_Flys wrote:
Fri Jun 23, 2023 12:05 pm
A hose might slap you in the face but it won't stab you.
That's if the belt doesn't eat the hand that's holding the hose. No matter what you use, there are only two safe ways to do it, very carefully or not at all.
:wink:

mdmellott
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Re: Serpentine belt confusion YD25DDTi

Postby mdmellott » Fri Jun 23, 2023 11:45 pm

Heyman wrote:
Wed Jun 21, 2023 6:03 am
Ok changed the belts was pretty easy as in loosen the bolt and release tension, changed both belts will upload diagram for this layout

Problem now is belt is squealing now and again when starting any ideas, pulleys all turn by hand (ac alternator)

Squeal lasts until over 3000 revs sometimes get a clicking sound near alternator but can’t be sure

Any ideas? I used a little deelectic grease on the groves
Two problems here. If you can turn those pulleys by hand, the belt tension is too loose and that will make the belt squeal. Grease is good for lots of different mechanical squeaks and creaks but never, ever should it be used on a serpentine belt. That will make it slip, especially if it's already too loose.


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