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Blue timing belt noise..

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I recall reading somewhere about people experiencing  a whistle noise emulating from

the new blue timing belt, something to do with its construction and needing a different

tension..I  had a search but can not find the thread. Was it on the forum or did i read it 

somewhere else..?

 

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Found it, thanks...

It does seen that when the same tension as the std. is applied to these blue belts, after a short time

they generate a high pitched whistle.

At first it is very difficult to identify the origin, it sounds like it comes from the tension bearing. If you

study the whistle it does change pitch occasionally when the rev's are constant which would seem to

rule out the Brg.  Also it does not have that duff Brg, sound.. 

I would be interested in anyone else who has experienced this, with possible solutions.. 

 

Dave

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Dave

some new bearings supplied in the USA squealed after a very short time, someone opened one and found no lubricant.

I reduced the tension on my blue belt to rid the whine.  the two sounds are not the same however. the belt zings and whirs, the bearing has more of a squeal.  certainly easier to distinguish between the two when one has had the privilege that I had to hear them both :(

the common belief and mine too is that it does not stretch as much as stock belt, so if tension is set cold to stock spec, there is too much tension at engine operating temperature.  after a short use (4k miles),

I disassembled engine to find that the 1st main bearing had serious wear only in the direction of the head.

perhaps a more scientific method would be to measure the tension of the stock belt with engine hot, install and tension the blue belt to same measurement also with engine hot.  then measure blue belt tension with engine cold for future reference.

not a perfect method, but a rational start

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Dave,

 

Have installed several blue belts and personally, I prefer the stock belts due to the tensioning issues and I'm going to change mine every couple of years anyway.

 

As Chris said, belt whine is common but I wouldn't describe it as a whistle at all so I'm thinking your noise is something else like the tensioner bearing. The blue ones I've done all sound like a typical timing belt that is too tight like the clip below. This one was actually set a little below the tension spec for the black belt.

 

Let us know what you find...

 

Jim

blue belt whine.wmv

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Dave,

 

I haven't used the blue belt, same reasons Jim mentioned, and I change mine often.

 

I had a weird noise after the head was machined, and it was the belt rubbing on the pulley, since it was running towards the front of the engine... Machinist had tapered the head.

 

Later I got a really strange noise after replacing a check valve between the intake manifold and the crank case breather!  It was the new check valve was trumpeting intake noise through the air filter box.

Sounded like this (cell phone format)

https://drive.google.com/file/d/0B2nifoCpaFSfMjY3MzZmNmEtNjVhMi00OTdmLWE4NTYtYjkzOTgzZDFmNWU3/view?usp=sharing

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