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I am looking into rebuilding my 86 6.9 since it is burning oil. I read that International put soft rings in the engine and that can be corrected when rebuilt. My only concern there is that harder rings will wear the block. Anyway, I am trying to do this on a budget and therefore want to reuse as much as possible and avoid any unnecessary machine work. So what can you tell me about the block and heads per say. If the cylinders walls are clean and are not wore can I reuse the pistons and put new rings in them? I suppose that the cam and crank will need to be machined, they have on any gas engine I rebuilt, or can I just put new bearings in if they spec out ok. Do the heads have replaceable valve guides. I am looking at a rebuild kit that is for a international 6.9 and am told that this is the same kit. anyway what should I be on the lookout for?
What condition is the CDR in?
Has it been serviced recently?
How many miles on the engine?
As far as the rebuild, the best answer there is have the machine shop check everything.
Replace everything that is worn or out of spec.
Check the heads, valve guides, valves and valve springs.
I had everything magnafluxed in mine.
I also did a minimum bore, so I had fresh cylinder walls, new pistons and rings.
All bearings replaced, crank polished.
New cam and lifters.
I also used 7.3 rockers instead of the stock rockers, much stronger.
I have about 2500 in parts and machine work in just the engine, I did all the labor myself.
What condition is the CDR in?
Has it been serviced recently?
How many miles on the engine?
As far as the rebuild, the best answer there is have the machine shop check everything.
Replace everything that is worn or out of spec.
Check the heads, valve guides, valves and valve springs.
I had everything magnafluxed in mine.
I also did a minimum bore, so I had fresh cylinder walls, new pistons and rings.
All bearings replaced, crank polished.
New cam and lifters.
I also used 7.3 rockers instead of the stock rockers, much stronger.
I have about 2500 in parts and machine work in just the engine, I did all the labor myself.
Not really sure how many miles, I bought the truck used from a St. Vincent De Paul. The odometer says 66538 but is is a 86 so there is good chance that it turned over twice. But who knows I have seen farmers here buy a truck and just use it to travel between the feed store and home and he only lived about 5 miles away. Or maybe someone just used it to tow a RV with it does have a heavy hitch on it.
Is it burning oil through the rings, or the CDR valve. When you pull up the air filter, look in the intake and see if it is all wet from oil at the CDR mount. If it is wet, I would service the CDR first. I serviced mine and my oil consumption was stopped.