Knocking noise

[Callumbh5]

Hey team,

My VN has developed a wobbly knocking noise coming from behind the motor,

Happens on idle and in drive, will sometimes stop while at the lights but then come back again.

Gets faster with slight revs but the noise disappears with more revs or when driving over 10-20km

Done some
Research and seem to think it could be the torque converter or flex plate, any ideas team?

 

[MikeC]

What's the fluid like in your transmission- right level? red colour? no metal particles?

 

[Having A Break]

Loose torque converter bolts.
Can sound exactly like a 'big end' knock.
Pull inspection cover and inspect.

 

[Callumbh5]

What's the fluid like in your transmission- right level? red colour? no metal particles?

Fluid is on the middle of the gauge of the dipstick, the fluid and filter was changed 5000km ago I had cleaned the pan and the magnet before resealing.

 

[Callumbh5]

Loose torque converter bolts.
Can sound exactly like a 'big end' knock.

Might be the case I think, do they come loose? I don’t think it has ever been taken apart.

 

[Having A Break]

....I don’t think it has ever been taken apart...

Unless you've had it since new it's hard to know lol
The bolts have sealer applied from factory, so there is only one way to find out...

 

[Callumbh5]

Unless you've had it since new it's hard to know lol
The bolts have sealer applied from factory, so there is only one way to find out...

I had a quick look today, Couldn't get the inspection plate off without taking off the exhaust so I’ll do that tomorrow.

Managed to see where the torque converter bolts to the flex plate and looked the the bolt was only half way down the hole, are the converter bolts that short? or do you think it’s worked it’s way out based of that observation?

 

[MikeC]

I had a quick look today, Couldn't get the inspection plate off without taking off the exhaust so I’ll do that tomorrow.

Managed to see where the torque converter bolts to the flex plate and looked the the bolt was only half way down the hole, are the converter bolts that short? or do you think it’s worked it’s way out based of that observation?

The torque converter to drive plate bolts are supposed to be torqued up to 40-50 Nm. That looks like your problem- I can't see GMH using short bolts that only go halfway down the hole. If the torque converter is removed from the drive plate new bolts are supposed to be used for reinstallation- the bolts are that important.

Can you rock the drive plate without moving the engine at the ring gear? That would confirm that it's really loose.

 

[hademall]

Engine mounts okay?

 

[Callumbh5]

Hey lads, I checked the torque converter bolts etc and nothing was loose.

After giving the torque converter abit of a hard shake it has the slightest of play back and forth but nothing feels loose.

Couldn’t find any cracks or deformities in the flex plate

If I put a pole up to the bell housing the noise is definitely coming from there. I’m suspecting either the torque converter is busted on the inside or it has something to do with the slightly leaking rear main seal.