Ouch thats a heavy knock by the sounds of it.....
I wouldn't say that is lifters - too heavy - in my ears anyway....
I am tempted to say big ends, whip the sump off, take the bottom con rod shell off and push the piston up (easier without plugs in) and see what the bearing shells look like.
If they don't look too worn, I'd be even more tempted to pull the heads and check the liners!
Do you have any other symptoms? Over heating, bubbling coolant, losing water, exhaust gasses in the coolant, mayonnaise under the oil cap, lack of power, ???
The fact it happens from cold - could mean it is not a liner (as these tend to move about when the block gets hot), but if it is especially loose they can knock from cold - but lifters and big ends will tick from cold also....yours does sound quite a heavy knocking....
Also, as the knocking dies off when revs are winding down, could also mean big ends - as the piston are not being 'driven' into the crank and are just following it on the wind down - then when you rev up, the pistons are being forced down onto the crank again....
I wouldn't say that is lifters - too heavy - in my ears anyway....
I am tempted to say big ends, whip the sump off, take the bottom con rod shell off and push the piston up (easier without plugs in) and see what the bearing shells look like.
If they don't look too worn, I'd be even more tempted to pull the heads and check the liners!
Do you have any other symptoms? Over heating, bubbling coolant, losing water, exhaust gasses in the coolant, mayonnaise under the oil cap, lack of power, ???
The fact it happens from cold - could mean it is not a liner (as these tend to move about when the block gets hot), but if it is especially loose they can knock from cold - but lifters and big ends will tick from cold also....yours does sound quite a heavy knocking....
Also, as the knocking dies off when revs are winding down, could also mean big ends - as the piston are not being 'driven' into the crank and are just following it on the wind down - then when you rev up, the pistons are being forced down onto the crank again....
