Worrying noise, possibly gearbox?

[tonyhawk]

I know there are a few posts on gearbox noise, which I have read, and I have also read the brief description of 'normal' noises on the mkiv NZ site, but I am still a little concerned.

 

When I rev the engine, it sounds gorgeous, but on the over-run there is a rattle, which can be felt as a repeating knock, almost like the flywheel is catching the bell housing (which it isn't, I checked). I have just replaced the flywheel and clutch, so it's not the old dual mass dying, and I'm hoping that it's just the normal noise that everyone has described, but it's the knocking feeling that's worrying me.

 

When you stick your head under the car, the noise is definately coming from the bell housing/gearbox area, and it significantly reduces when you put the clutch to the floor, as does the knocking feeling.

 

The thing is, it's been off the road for 18 months, so I really can't remember if it was there or not before, but I'm fairly sure I would have noticed it? Also as it has no MOT, I'm not able to take it for a spin, and see if warming the gearbox up reduced the noise! Most annoying!!!

 

Please, any ideas?

[bignum]

hi mate,if the noise is coming from the bellhousing area it could be the thrust bearing,mine has a slight rattle when ticking over then dissapears when the clutch is pressed,hope this is any use to you.

[tonyhawk]

Thanks, but I think it's a little worse... I have just been out for a cheeky test drive (no MOT, not tax .. ), and the knocking is awful. Worse yet, it didn't go away (much) when the clutch was depressed.

 

Just to add a nice ? factor into all of this, I am getting two seperate oil pressure readings; I have an oil pressure gauge, being fed from a sandwich plate behind the oil filter, which when at low revs, such as at a junction etc., is reading about 40psi (ish), yet at that point, the oil pressure warning light (which is being fed by the normal switch behind the air con pump) comes on!

 

To makes things seem even worse, the flicker of the warning light corresponds exactly with the noise and knocking/revs, and goes out when the revs climb, and the pressure reads 60+psi on my gauge.

 

I'm really lost at this point, and if I had the cash (which sadly I don't at the moment) I would gladly throw it into a garage and say "fix it"!.

 

Please, if ANYONE has any ideas, about any of this, I could really do with some help...