md,400,450 diesel engine query

after removal of the head (400d) couldn't help notice excessive carbon and soot on the cylinder sleeve bores. all four of them. the area from where top piston ring would stop to the top of the sleeve.
i just overhauled a md last year and that didn't have this excessive build up. the md had a lot of hours on it and needed a rebuild.

this 400d (recently purchased) looks like it had a rebuild recently as hardly any lip in the sleeve and the head looks like it was reburnished lately. but it was missing badly in what seemed in 1 cylinder to which is why i took the head off to inspect the valves and i also wanted to inspect the pistons and sleeves.

but back to the original question about the carbon and soot buildup. would this be normal or should i be looking for something?
sincerely,
tim

Interesting,
Most engines, while in operation, do not touch that area of the cylinder at all. Thus there is no reason for deposits to "wear" off. But if all had the Sooty deposits, and very much if, the tractor had been operated under load for at least 4 or 5 hours prior, I would suspect it was using oil pretty heavily. If the tractor was not brought to temp in the last few times it was run, I would say it was very normal.
Personally I think diagnosis by pulling the head may have been (with respect) premature. Diesels (especially the options with the gas start/diesel run engine) can be diagnosed to high reliability fault finding with the head on. Particularly the fuel injection system.
What to do now:
turn the head to a position so that the intake and exhaust runners face up on the bench (with the valves and injectors, and not the spark plugs, are in place). Tap each valve with a plastic hammer to make sure it is seated (crud can get into the face seat during disassembly). Then fill the manifold runner to each valve with diesel fuel. If fuel runs out the valve to head interface, the valve (or seat) is bad. If after an hour some diesel gets through I'd say it is OK. Some will get through the guides, if dramatic, the guide is bad. If it leaves the runner, but ends up in the water jacket, the head is cracked at the runner.
Set the head so the spark pluge are up. Fill the compression relief chambers with diesel. the third valve should also hold the fuel as above.
I would have the injectors tested at a good diesel shop, (if it had been still together, cracking the fittings on one cylinder's injector line at a time to find the miss, followed by compression checks and swaping injectors from cylinder to cylinder would have been my method of testing. Best of luck. JimN