dusted cylinder

[tdburnette]

Can anyone try to explain me what a dusted cylinder looks like? I have a 753 that has less than 70psi on all 4 holes. When torn down the cylinders are rough and dark colored on the upper 3/4 of the cyl. the lower 1/4 looks like it should. Maybe not dusted but what caused this? thank you, Terry

 

[thetool]

It may be normal wear on an engine, especially if you have no vertical scratching or scoring in the cylinders.
An engine that ingests unfiltered air containing fine dust particles will do this also at an accelerated rate. It can look like normal wear-out that occurred in just a few hours, tens or hundreds, depending on how much and how dirty the incoming air was.
So, the cause is either normal wear(a well maintained Kubota can go over 5000 hrs easily) or unfiltered intake air, due to no or plugged air filters, or a rip in an intake hose, or an intake hose that wasn't secured to the air cleaner or intake manifold.

 

[Tazza]

It may be normal wear on an engine, especially if you have no vertical scratching or scoring in the cylinders.
An engine that ingests unfiltered air containing fine dust particles will do this also at an accelerated rate. It can look like normal wear-out that occurred in just a few hours, tens or hundreds, depending on how much and how dirty the incoming air was.
So, the cause is either normal wear(a well maintained Kubota can go over 5000 hrs easily) or unfiltered intake air, due to no or plugged air filters, or a rip in an intake hose, or an intake hose that wasn't secured to the air cleaner or intake manifold.

I too have never seen a dusted cylinder wall, but i agree it depends on what it had enhaled. Fine dust would look like normal wear.
What does the inlet manifld look like? is there any dust in there? or the inlet hose? thats the best way to know if it was dusted.