H6 Subaru current model six cylinder engines.
A new short is being supplied under warranty for oil consumption engines. We have only just received the first one of these as it has been an in-house engine build and didn’t give us access until now.
The new short comes fully assembled with rods, crank and pistons in. But they also send a full set of new pistons and rings with instructions to replace the original pistons and discard them. Their story is that the ring grooves are machined out of square on the pistons in the new short and will give oil consumption.
However, we observe vertical honing chatter in the oil-burner engine and wonder. We have both the old and the new engines in the shop.
From what we have seen of the EJ25 engines, they also have this vertical hone chatter associated with oil consumption. Only visible after the engine has tried to run in. It would have no hope with the light weight oil control ring of today.These rings will just skid along the ridges of the chatter and the oil runs up the centre into combustion.
Watch for the same pattern in Gen 111 engines.
