How do you know when it's time for an inframe?

Have you ever done a small block chevy? A big diesel is a hundred times simpler. An inframe on a 12.7 is 25 book hours. Taking my time and not hustling hard, i can get it done start to finisish over a 3 day holiday weekend, assuming i got all the parts and don't gotta wait on them.

Drain the coolant. Drain the oil and drop the pan, remove the oil pump. Pull the valve cover, 12 bolts gets the rockers (note the position of the rocker assemblies they are not marked like they should be and if not installed back in the same position you block the oil holes) and jakes off. Remove the cam gear access plate and remove and lock the gear with that weird triangle shape tool(do not ship this strep unless you enjoy spending an entire day timing an engine). Remove the cam bearing caps and lift it out. Remove the 38 head bolts and the head is ready to come off once you loosen intake pipe and exhaust pipe. No need to pull the manifolds if they aren't leaking. But I would pull the injectors to see how the cups look.

If there is any question to the condition of the injector cups or valves, just buy a new head. It's under two grand for a complete remanned head and most machine shops want over 1500 to do a head. Be sure to take the cam bearing caps with your head or they won't give you core credit.

Go back under and pull the rod bearing caps and push the rod and piston up. Big time saver if you got someone on top to lift them out once you get them pushed up so you aren't climbing out from under the truck so much. Pull the piston oilers while under there. After all the pistons and rods are out get up to and pull the liners if you got a liner tool. Or get under and use a jack and flat piece of steel you've cut to fit. Once they are out check the condition of the counter bores.

Detroit used to say that less than ten percent of the ddec3 and 4s would need the counter bores cut and shimmed, so chances are you won't need that. If you do your only options are to pay an engine builder to come out and cut them, or buy the tool. For what its worth i have rebuilt over a dozen 12.7s and none of them were in bad enough shape i couldn't clean them up with a bit of emory cloth and elbow grease. I also like to spend an hour with some emory cloth on the top of the block to get it perfectly clean, at this point my elbow and shoulder hurts enough that i call it for the day. Put it all back together the next day. Use a block of 4x4 and 3 lb sledge to set the liners. Check them with a sled gauge. Do the pistons one at a time, don't forget to lube the bearings and pistons. I use Lucas oil stabilizer for this. (Side note, this is the only time Lucas ever enters one of my engines.) Put in the new oilers. Now do the main bearings. Only loosen them one at a time or the crank can flex out of position and if that hapoens you are screwed, you will have to pull the block to set the crank right. Use a big cotter pin in the crank oil holes to roll in the top bearings, much easier to have someone to turn the engine over as you do this, but you can do it by yourself from underneath with a pry bar on the oil pump gear. Put the oil pump back on and the bottom half is done. Up top you put on the new head gasket and very carefully lower the head back in place. Download and print out the proper bolt sequence and follow it. Doubtful you have the new style head bolts so don't reuse them, they have stretched. The inframe kit will have new bolts. Install the cam and can bearings, lube them. Put the jakes and rockers back on, adjust the valves. Put the valve cover and pan back on. Prime the fuel system. Cross your fingers and crank her up.

I'm sure i forgot a step or two but my main point was is a real simple job. If worried about it, order an engine manual. Might be a good idea to have that on hand anyway.

Edit to add: Google detroit service manual and you will find lots of places that carry them. Mine was 180 bucks. As for tools, you need the injector height tool, the cam gear lock tool. And a big 3/4 inch torque wrench for the main bearings. A liner removal tool is nice, but not necessary and you can easily make it with some stock steel and a piece of all thread. Everything else is standard sockets and wrenches. A very deep socket for the rear rocker assembly nut can be made by welding 2 normal deepwells together. Apex tool company stocks almost everything if you want to buy them instead of make them.

 

http://www.blackstone-labs.com/ this is the co I use for my oil test.

 

If it doesn't use oil, runs great and still gets great fuel mileage, don't worry about an in frame, change the fluids, get valves and injectors adjusted and run it, sounds like it still has tons of life left in it, don't fix something that isn't worn or broken.

 

Reading that last sentence... I know you talking bout me!

 

I just get them from my local freightliner dealer. But I've got 20 years history with them so i get a fairly decent discount off list price.

Some after market suppliers are good quality. After all, it's not like detroit owns a steel plant to make the pistons and liners. Just do your research on whomever the supplier is of the parts you get. You might find out that truck pro or fleetpride gets their heads from the same company that supplies detroit, just won't have detroits stamp on the card board box.

 

Curiosity here. Why do you suspect it is time to tear it down? If it's not burning oil then the pistons are still tight. If it's high on mileage it would be smart to slap some bearings in it just in case. They are cheap and easy. I wanna say a bearing kit is something like 350 bucks and easily done over the weekend even by someone who has never done it before.

 

I've never dug into a Series 60, but I've torn a Series 50 down and put it back together. (from what I've been told, its simply a Series 60 with 2 less cylinders and balance shafts in the bottom end). I was a 2nd year apprentice mechanic at the time and it was honestly pretty simple.

 

I have used many many

I have used many many Clevite kits with good results. Started using them because I saw many Clevite bearings in engines that had them from the OEM.
Many if not all engine companies contract much of that out to companies like Clevite, TRW, Badger,etc.
I used to do some mail order engine kits. Then I had one with damaged area on top of a liner, surely concrete floor test. The company made it good but I had to pay for the replacement parts and freight to ship the old one's back. Then get a credit later less freight. Now I get parts through a local company, pay a little more but get better service or direct from one supplier.
Heads is the wild card. If you are doing your own or someone else's what is the warranty? Has a bad valve guide or seat. Fixed it and here is a head gasket set! See ya next time. Oh you are not a certified mechanic blow smoke and it is your fault. I normally use factory remans on the big boys.
Cummings a few years ago would cover parts and labor if you bought everything from them and had a warrantible failure. Take it to them and they fixed it.
Just sharing and it is only my opinion. Plan your maintenance and save up for the unexpected because it will show up.