Nick Graves

That's the old Shell Rotella trick; 50-weight heavy truck oil masks all manner of clearance sins.

sleepysnake

I had read about that trick.

Over my ownership I have put in around 5 litres of 5w 40 oil. I would have thought if the previous owner used a heavy oil to mask the knocking, all of that would have been burnt off and replaced with the conventional oil.

Tom noted that the oil that came out looked very thin and had the consistency of a 0w oil.

The oil change did not do the engine any good though. Perhaps it may have been forcibly trying to replicate the buzzing/knocking symptoms as a demonstration that pushed the poor old bearings over the edge.

JMoura

My car does some noise when warming up too. If I blip the throttle, it seems to go away and I can only hear it from the inside. It sounds a bit like yours on the the first video you posted. The knock is a bit difficult to pin point as the TCT and valves may sound very similar to a bad rod bearing!

sleepysnake

Not sure if this is what you get JMoura, check out the first video.

Here is the video from this morning. Today it sounds significantly worse. It looks like my hopes of dropping the sump and replacing the rod bearings if the crank looks OK are probably now over.

Sitting in the car and displaying the knock (about 5 mins after start): https://youtu.be/33-JHUNGDvo

Fairly long cold start video: https://youtu.be/ROuCwIQdTTQ

westburywheeler

Dosnt sound like big ends, have you had a look at the belt tensioner, take the belt off and check bearings, use a long screw driver as a stethoscope and check around see where the noise is worse, might give some clues, good luck.

JMoura

Just watched the videos.
When the engine is cold, it seems to be healthy. I'd consider the noticeable 'tick'(especially when you're filming under the car) normal, as it seems to be normal engine noise from places where the oil is still trying to reach.
When the engine is warm, the knock is very obvious :/
I hope the damage is not too extensive and you can get around it by selling the current engine and sourcing a healthy one.
Best of luck!

Nick Graves

Does it do it with the clutch pedal depressed?

The revs dip too low when you release the pedal and it sounds more like clutch plate or gear lash.

Maybe even crank walk...

s2k4tony

I thought that.

Perhaps is the timing out / running too lean? I'd be looking at clearances, get them seen to. Give the thing a complete service including new plugs. I know it might make no difference, but try 10w 30 instead. Don't raise the oil debate, but you never know!
More importantly it could well be the tolerances set by engine builder - so after all of the above has been attempted with no change, you could be on end of a slowly failing block. Hopefully not. Drive with care

sleepysnake

I think it may be something to do with the timing. When the engine was opened up previously it had the cam sprockets and all timing associated bits replaced. I understand you need to adjust the valves after that so perhaps it wasn't done properly.

That nasty knock like sound in the video of me revving it in the cabin is only heard when it drops below 500 rpm and is not really heard when warm. Though this only started happening after the oil change which is puzzling.

The engine buzzing, which I don't think sounds like knocking still happens as it always has between 2 and 3k rpm on a light throttle. For now I will put up with it with a view to find someone to adjust the valves properly. I don't know if my local Honda dealer will be able to do that.

sleepysnake

The clattery / buzzing sound at around 2800 rpm seems to be coming from the cylinder head rather than the block, according to my mechanics stethoscope. Sounds like it might be timing chain related.