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So, I recently had a 100,000km service done on my R34 GTT which included installation of a new timing belt. Since this new belt was installed I now have a noise once the engine has warmed to operating temperature. The noise would best be described as an oscillating noise (only present at idle), and the mechanic told me it was due to the type of timing belt that was supplied with the kit.

Apparently the belt supplied with the kit for the 100K service for an R34GTT has changed and is now a "racing" spec belt, blue in color and made from a stronger type of material. The belt has been tightened to the required spec and has subsequently been re-checked by the same mechanic, but the noise remains. I have been advised (by the mechanic) that the same noise exists in a recently serviced R33 which had the same type of belt installed. He said it was nothing to worry about and a common result now that this type of belt comes with the kit.

So I am seeking some advice here on the forum to see if anybody else has had the same issue/result.

Q. Is my mechanic pulling my leg here? I have sought a 2nd opinion from another mechanic who told me that the tension on the belt is too tight if set at the required specification and the noise can only go away by reducing the tension (slightly) on the belt. He advised me that I risk breaking a belt if left like it is, with possible additional damage to the engine.

Q. Is this correct advice?

Any feedback or advice from you guys would be appreciated. The noise wasn't there prior to the 100K service, so I am of the opinion that it shouldn't be there now.

Cheers,

mick :excl:

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Hmmm I had a Gates Racing one put in my R33 (I'm assuming this is what your blue one is) and I don't remember any different noise. But then again my R33 was pretty old and clunky haha

I have done my R34 recently but not with a blue one.

Thanks for the hasty advice and reassurance guys. I did some additional research on the forum and yep it seems to be a common issue with the Gates timing belt. Apparently it may go away after a period of time when the belt settles in. Glad that this is not a big issue anymore.

Woo hoo :thanks::banana:

Just received a PM with some advice regarding my noisy timing belt issue and I thought I should post it here for all to read as I think it warrants consideration. In the end I guess you should make your own decision to look further into this type of noise, but after reading this advice from someone with first hand experience in this I think I will be visiting my mechanic to get the belt retensioned or better still replaced.

Here is the advice:

-----------------------------

And there you go, 2-replies to your post and both wrong.

The noise is not normal, it's simply your choice of belt, If you'd fitted a factory belt there would be no noise.

I explained all this to a guy with a 33 GTR only a few days back, he posted in the Skylines and other vehicles section.

Exactly the same problem and fixed by setting the Gates belt slightly looser than the factory spec.

A Gates belt is quiet on initial start, but as the engine warms up dimensions grow.

A factory belt has slight stretch and will accommodate the change in dimension, not a Gates belt, they're way too strong.

So now you're driving with an overtensioned cambelt, what can go wrong.

The noise is the idler bearings. If they collapse or the same for the tensioner or perhaps snap off the idler centre bolt, you'll have valves hitting pistons.

The other problem is an overtight belt damages the front camshaft bearings.

When something breaks and your engine is ruined, I can guarantee the mechanic will walk away as he's fitted a non standard part yet tensioned it correctly. You can't win in cases like this, especially if you supplied the parts.

Easy fix is to do the job again but this time set the tension slightly less than factory.

BUT remember all this and never use Gates crap again, there's simply no need to use such belts. Even RIPS making 1000hp uses a factory belt.

I went on to explain to the other member how Gates makes it attractive by supplying all the items in a reasonably priced kit. They also do kits for other cars and one I have a lot of trouble with is the RD28 in the Nissan Patrol. It does exactly the same thing but as they're diesel you can't hear the horrible noise and they will snap the camshaft wheel right off the cam, then put the valves through the pistons. You buy a new engine for these things, that's how bad the damage is.

Raved on a bit but I can't believe guys who say such noise is acceptable, they're just wrong.

If you google up cambelt noise you'll find u-tubes of exactly your noise. A recent one is by SargeXR8 from this forum.

He did his tensioning at least 3-times before getting it right. I told him straight up what the problem was and he's happy now.

I've done loads of cambelts in all my Skylines, never had a fail until my GTR which got a Gates belt, so I know the noise.

Never using a Gates belt again.

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