Detroit 60 series 12.7 big block

When they first made the series 60, after inspecting bearings, Detroit upped the interval to 750, soon there after 1 mil. It’s all documented online, somewhere. They were the first engines to go past 500 k for rods and mains maintenance. I’ve seen them on two different engines I’ve owned, 875k, and 1.2+ mil. They still looked good. Oil pressure will drop if they’re worn. So good pressure usually means good bearings. The problem I’ve had twice, is a dropped liner, at 875k, on 500 hp engines, with upper cooling jackets in liners. Yours probably doesn’t have that. It’s supposed to help cool and avoid upper cylinder scuffing. But It’s debated whether or not it promotes coolant cavitation. Keep coolant additives at proper levels. Cheapest insurance, often neglected. Causing a pin hole in liner sleeves and liner pitting around head gasket fire ring, resulting in blown head gasket, dropped liners. If that don’t get you, antifreeze running down the right rear side of the block, mixed with some oil will. Those things are more likely than a bad rod or main bearing.

 

No, rocker shafts. Not rocker arms. If worn you rotate them, Keep detroit emblem on ends facing out.

 

Pre-egr Series 60 are inexpensive to rebuild. Step 1, basic rebuild is offered at most Detroit shops for around $7,000. That is with a 1 year 100,000 mile warranty.

 

Ain't broke don't fix mains and rods last a while

 

Reman rocker assemblies were $2100, mine still seemed good. So by flipping shafts, The arms need to be flipped on the shafts also. Do you swap arms out to other shafts, or keep them the same? Do they then ride on new metal of shafts? Or same. Seemed to be same, as they looked the same. What about putting new bushings in the arms? They’re cheap, but can they be changed? Pressed in? The remans I’m guessing are just re used if in spec, with new bushings installed I imagine. Mine looked great at 2.2 mil. All the buttons look new still. Same with the nylon rollers.

 

Watch along the head gasket on passenger side rear especially. Right below the exhaust manifold. Also watch for oil leaking around exhaust gasket, and oil going towards the turbo. Mine was blowing oil into exhaust pipe, The valve guides were so bad the valves were slapping 3 of the six pistons.

 

12.7 detroit big block?

 

You will see or feel the wear on the shafts. Its shinny, compared to darker metal of un used side. I'm sorry but I do not have the name for the process of metal finish. More of a gun metal look. But per DDC its acceptable to just flip them. No need to change rocker arm bushing of they measure in spec.

 

These strips are used to test coolant. Very cheap insurance. They have a shelf life. No need to buy a lot at a time. Check as part of normal pm oil change. Add pencil or equivalent to achievie proper color on strip. Ideally test strip matches reading for 2400 too Little or too much additive causes problems. Pre mixed Red Final charge has additives already. Still have to check and add as needed. Sometimes only once a year or longer. Best to test, to make sure.