Timing Belt Noise Issue After 100,000Km Service

[ozcanGTT]

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:

[boostn0199]

Yep perfectly normal for the gates belts to be louder than standard same on everyones.

[Victory]

Gates racing belts are a good quality timing belt. They are blue and are normally noisy when they are fitted - some quieten down after they wear in and others remain noisy depending on your engine.

So if it is a Gates belt then your mechanic is correct in what he has been telling you.

[ozcanGTT]

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

[ozcanGTT]

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.

[Dose Pipe Sutututu]

IMO, stock is best.. I believe for street cars, GATE belts are overkill.

I've always used stock belts during a change and they are fine for bolt on mods, power, etc. Have you ever heard of a stock belt snapping from streetable power?

That's my opinion, others will think differently

[D.I.Y. Mik]

Now im scared to fit my cheap timing gears,

anyone know if they can be dodgy?

[Moodles2]

I don't see any issues with cheap cam gears, I run a pair myself. The problem is the cheap fasteners that come with them that are the problem, if they let go the cam gears will go to one of the extremes (20 degrees advanced or retarded, I can't remember which way) that will 100% guarantee bent valves. Solution is to replace them with hi-tensile bolts which costs virtually nothing.

[D.I.Y. Mik]

awesome thanks

[Carbon 34]

Same boat here , gates timing belt and all new pulleys etc , cold no noises, warm to hot random whime like a supercharger

Mechanic said cam gear profile was slightly diff ?

Called gates tech , he said never issues unless its a dud idler , mine are brand new

The too tight syndrome doesnt seem right too tight would whine cold not hot

Cant be idler it did it right after install

kevlar doesnt contract and expand ( i deal with it often )

asked a skyline spec mech said never gates only factory

Comflict i grew up down the road from gates usa and in 35 years of car and gates never had issues till now

i just don't want a rb melt down till i can afford to drop in a stroker motor ( farking thing just dump a turbo found it wasnt stock from japan ) and nissan wiring sucks balls crusty

might keep digging , the noise isnt such a big deal as long as no damage is done

[Moodles2]

Possibly the CAS wasn't put back on perfectly.

[34GeeTeeTee]

Hmmm mine was just fitted up last week and should start this week, will see if the noise is there... Hope not

[DVS JEZ]

Nearly every gates belt is whiney. Most nissan belts do it if they are a little tight

[34GeeTeeTee]

Nearly every gates belt is whiney. Most nissan belts do it if they are a little tight

The profile of the teeth look right so there is no real reason for them to whine?

Should be sweet

[scotty nm35]

kevlar doesnt contract and expand ( i deal with it often )

Its not the belt shrinking, its the engine expanding as it warms up. The Gates belts must stay the same size with no stretch which makes it tighten as the engine expands. Will leaving it a little loose cause it to skip teeth though? I doubt it.

[rb2534]

I have exactly the same issue on my 34, I got supplied a Greddy belt as they couldn't supply me the belt I ordered. Ive done a few thousand ks since the service and thought it would quieten down but it hasn't. The belt was set up exactly like ones I and my mechanic have done in the past.

[Carbon 34]

Spoke to a few other tuners and gates again

they say nissan factory is best ( i disagree for many reasons ) but hey the problem seems to be a belt tensioned with the motor cold as ice

the belt deflection doesnt exist when hot and it rides tight as fark on pulleys and tensioners

my cas was fine , checked a few times since i changed a mountain of parts in that area lately

the belt issues exist worldwide on all types of cars

The mechanics dont know the fix in most cases but this is my findings

The noise is worse with carbon covers ( more echo)

oh and i found out the GReddy belt is made by gates as well so the above problem would be consistant with both belts, they make a few major jap belts for racing

i would still buy the gates belts but install it myself if i wasnt injured at the time grrrrr

Gates makes street and race belts blue is race , black street in case anyone wonders

ditching my new bosch belts on the external pulleys for blue racing from gates next , they match my underdrive alloy pulleys lol

[Moodles2]

Sounds like your problem is with Nissan, having no confidence in their OEM gear. The whole thing people get suckered into the Gates racing belt is that "300% stronger" spiel... if the factory belt will last 100,000km... are you expecting 300,000km out of the Gates belt? The difference between Gates cam seals and genuine OEM cam seals in the rubber quality is massive, the OEM is a soft rubber that looks like it would seal well while the Gates was hard as rock. Not to mention the Gates RB cam gears are the same flawed design as HKS with the 3 sliders instead of 5 which every other cam gear has. The point I'm making, is everything Gates make great? no.