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JeepSJ
04-29-2016, 09:32
I'm starting this thread to cover the build of a Navistar based engine for my DieselWag. Details on the purchase of the block is here - http://www.thedieselpageforums.com/tdpforum/showthread.php?t=44595&page=2

I have the 2009 block totally stripped and ready for the machine shop. It is getting dropped off tomorrow. While most of the cylinders didn't show any visual wear, one cylinder has some really strange erosion in the top 1/4", so totally above where the rings contact the bore. The rest of the block is spotless though. If it won't clean at .020, then I'll just have that cylinder sleeved. The rest of the cylinders all measured within spec and should be fine with just a fresh hone, so if the bad cylinder needs a sleeve then I'll run the block at a standard bore. Otherwise it will all go 20 over. The crank and bearings in that block looked brand new. The crank spun freely, as did the cam. Since I don't know the actual history, this crank will go up for sale and I'll be using a new Scat crank.

Got the other block stripped down also. Aside from cylinder wear, this block appears to be in great shape as well. Definitely rebuildable. The crank was trash though, thanks to some rough handling (one journal had a nice big gouge). As soon as the machine work is done on block #1 (or as soon as I know that block #1 isn't completely trash), this one will go up for sale.

DmaxMaverick
04-29-2016, 10:13
You may want to have a close look at that crank. It may be forged. Scat 6.5L cranks are not better than a forged GEP crank. Scat cranks, so far, haven't proved to be better than GM originals. They are an alternative, nothing more. While Scat makes some fine high performance forged cranks, the 6.5L crank is not one of them. It is cast.

JeepSJ
04-29-2016, 12:28
Crank in the Navistar block is cast.

I thought the Scat cranks were cast of a better material than the stock cranks?

So basically I should just polish this up and run it?