Originally Posted By: Doug Hillary
Various diesel engines have been and are prone to soot based sludging. Mostly it was/is due to using an incorrect Spec lubricant, lack of an appropriate OCI, breathing issues and etc.
I've never seen a diesel with sludge that doesn't come perfectly clean with a quick srub in the partswasher...that never happens with sludge in a petrol engine. Sometime early this century when small indirect Japanese diesels were very common here, I drained an engine and it slowly poured out like molasses. Who knows what that was or how long it had been in there I thought...but the next one was our oil and within the service period. Then every diesel we drained was like this. I talked to my oil rep about it (starts with P owned by S) but he turned into a politician and I didn't get an answer. Then after a few months things were back to normal. This was before we went low sulphur.
Is this what you are calling soot based sludge ? It was certainly an oil or fuel based issue. It was the sort of sludge a sludge pump would pump, rather than petrol engine sludge, which is stuck to surfaces and hard to get off. I took a rocker cover off one of these engines, it just washed off without any effort.
Various diesel engines have been and are prone to soot based sludging. Mostly it was/is due to using an incorrect Spec lubricant, lack of an appropriate OCI, breathing issues and etc.
I've never seen a diesel with sludge that doesn't come perfectly clean with a quick srub in the partswasher...that never happens with sludge in a petrol engine. Sometime early this century when small indirect Japanese diesels were very common here, I drained an engine and it slowly poured out like molasses. Who knows what that was or how long it had been in there I thought...but the next one was our oil and within the service period. Then every diesel we drained was like this. I talked to my oil rep about it (starts with P owned by S) but he turned into a politician and I didn't get an answer. Then after a few months things were back to normal. This was before we went low sulphur.
Is this what you are calling soot based sludge ? It was certainly an oil or fuel based issue. It was the sort of sludge a sludge pump would pump, rather than petrol engine sludge, which is stuck to surfaces and hard to get off. I took a rocker cover off one of these engines, it just washed off without any effort.