This past Monday I went to a local junkyard and picked up a 4.2 out of a '77 Gremlin for $100. It didn't give me any trouble pulling it at the yard, but on the way home a quick changing stop light caught me off guard and the engine rolled forward and slammed into the back of the driver seat. Yes it was still full of some ancient thick black oil in it, and yes it's now all over the carpet and rear seat in the XJ.
I hope this isn't a sign of things to come with this build...
Back on track: I got the block into the barn and tore it down to get at the goodies. The engine looked pretty good inside and all the parts appeared to be original.
The crank is a 12 CW (Casting# 3214723) and the rod and main journals look pretty decent but should still get at least polished, if not turned .010 at most, to clean it up. It passes the ring test so a crack is unlikely, but I will get it magnafluxed when I sent it to the machine shop anyway.
I cut out the center of the harmonic balancer with a thin cutting wheel on my angle grinder to make a spacer out of it. I'll turn the OD down to remove the remainder of the spokes and cut it to length on the lathe later. I'll try to remember to get pics of the process.
The rods are 707's and I'm going to shorten the top pads for piston clearance and polish the beams before I send them off to get reconditioned.
The pistons look like factory originals and don't appear to be oversized. I didn't bother measuring them since they're getting tossed in favor of some Sealed Power 677's. The new pistons will be getting dished to 30cc by Oleshot when I buy them early next month. I've just gotta contact him to let him know when I'll be sending them his way. For the cam I'll be using a stock '96-'99 replacement from Melling. Also on the shopping list are new lifters, double roller timing set and Mopar valve springs among other things. I already did a lot of the basic mods previously ('99 intake, full 2.5" exhaust, 60mm throttle body, slightly bigger injectors, hi-flow water pump and brass radiator) so I'm already that much ahead of the game.
Next order of business will be to pick up a complete '96 4.0 out of an XJ in another yard for $350. I may try to pick that one up on Monday since I don't have classes on that day. I'd rather pull the original 4.0 in the XJ, but I can't have it down that long since it's my DD right now. When the block goes to the machine shop it will be getting zero decked (hence the 30cc dish) and bored .060 over as well as the usual reconditioning machining. The head gasket will be a .043 MLS type to help get the quench down to the bare minimum for a better DCR. I'm not sure yet if I'll try to port the '96 head or not since I'm going for such a relatively mild build.
It's late and I've gotta get some sleep before school tomorrow so I'll post the entire build details this weekend.
