Noise In Top End

[TezGT-R]

The other day I started up the GT-R and after a minute or two it starts making a noise like a loose belt, like that horrid squealing noise. I open the bonnet to check and belts are all tensioned up fine, and the noise is coming from the top of the engine at the back. Right where the rear of the camshaft is.

After a couple of minutes it goes away, but the engine is now noisier, not the exhaust but the engine itself, though not clunking or squealing. Its hard to explain how it sounds, but it doesnt sound right and its louder. I drove it around the block and it feels like it doesnt want to rev as hard. Once round the block and I parked it.

Do you think I might have a dead bearing on the cam? I've got to take the rocker cover off to change the gasket anyway (slight leak) so I thought while its off I'd check the bearings to see if any are dead. Sorry to be so vague but I wanted a more learned opinion than my own before I shell out cash to fix something I can probably do myself, or destroy my engine.

Thanks guys

[eeiko321]

The other day I started up the GT-R and after a minute or two it starts making a noise like a loose belt, like that horrid squealing noise. I open the bonnet to check and belts are all tensioned up fine, and the noise is coming from the top of the engine at the back. Right where the rear of the camshaft is.

After a couple of minutes it goes away, but the engine is now noisier, not the exhaust but the engine itself, though not clunking or squealing. Its hard to explain how it sounds, but it doesnt sound right and its louder. I drove it around the block and it feels like it doesnt want to rev as hard. Once round the block and I parked it.

Do you think I might have a dead bearing on the cam? I've got to take the rocker cover off to change the gasket anyway (slight leak) so I thought while its off I'd check the bearings to see if any are dead. Sorry to be so vague but I wanted a more learned opinion than my own before I shell out cash to fix something I can probably do myself, or destroy my engine.

Thanks guys

well you'd hope its not a bearing....

im thinking it could be one of the pulleys?

sometimes even when the tension on the belts are correct... the bearing on the pulleys can be worn... especially on an old car like yours.

id inspect all pulleys...waterpump, power steering, Crankshaft Drive pulley & air condition first and go from there

[TezGT-R]

Thanks for the advice man. I've just had the timing belt done and the water pump. I think I'll take it into the workshop next week to let Trent have a look before I start tearing it apart. When I fix something it ends up taking six months, like the pivot bolt. Not much fun taking a GT-R gearbox out with hand tools and jackstands, I gotta say....

[eeiko321]

Thanks for the advice man. I've just had the timing belt done and the water pump. I think I'll take it into the workshop next week to let Trent have a look before I start tearing it apart. When I fix something it ends up taking six months, like the pivot bolt. Not much fun taking a GT-R gearbox out with hand tools and jackstands, I gotta say....

a good way to see if there is excess vibrations in a pulley..... is to get a long rod say 10mm or so in Dia...

rest it on the actual bolt where it pivots... then putting your ear at the end of the rod.

if the bearings are ok, it should be a low ...kind of a mild hissing sound...

then you could even say pull the throttle yourself and listen.

and beleive me, you will notice if its faultly.... whilst comparing it to the other ones.

cheers

[TezGT-R]

Thanks buddy I'll check it out

[GTR-N1]

a good way to see if there is excess vibrations in a pulley..... is to get a long rod say 10mm or so in Dia...

rest it on the actual bolt where it pivots... then putting your ear at the end of the rod.

cheers

^^^ +1 true

And 'wooden' dowelling about 1cm diameter is better than a long screwdriver.