Which cam and other questions

[TexasRed]

Actually now I've hit somewhat of a roadblock. When I have both # 7&8 pistons on the crank, it locks up. I have a feeling it's number 7, because if it's on there by itself, I can't get number 8 on there, but if #8's by itself, I can get #7 on there but when I do, it's locked. I thought I had fixed it by cleaning behind the bearing shells and the surface where the bearing goes on the rod and cap. But it seems not to have worked. Any thoughts?

[eventhorizon66]

When you say "locks up" you mean the rods seize the crank when installed?  I won't move at all?

Are the piston-rod assemblies correctly assembled?  First establish that the pistons are being installed in the block correctly (is there an arrow indicating the front of the piston?).  Then hold the rod big ends against each other (with caps removed) as they would be installed on the crank.  The bearing tang grooves in the rod should be at the opposite end and opposite side of the crank journal from each other.

Wasn't this a complete rotating assembly from PAW?  Try contacting them.

[TexasRed]

I've had it all together before and it turned. Yeah, the pistons and rods are right. Yeah locked up like it won't move at all. If I loosen the rod cap, it allows it to turn. I've checked to make sure the piston is put in correctly and the tangs are the right place.

[eventhorizon66]

Well what has changed since the first time you assembled it?  Are you installing the rod caps with the bearing tang grooves on the same side of the split?

[TexasRed]

Well I've narrowed it down to something with that rod/piston combo. I'd tried it on a different odd numbered journal, same story. So I'm going to try O'Reilly's during work and get me a bearing, maybe it's something there? I used some 000 or 0000 steel wool on the edges/sides of the bearings to see if that's it, but I haven't checked it yet. 2 sealed power bearing shells are like $3 so I'll try me that.

[eventhorizon66]

Have you attempted to install #7 rod/piston with the bearings from another rod?  That'll answer whether or not it is a bearing problem.  What is your clearance on that bearing?  If you haven't already, now would be a good time to confirm all the bearing clearances with some plastigauge.  Does the crank journal show any nicks or scoring now that you've installed/removed that rod a few times?  Is the crank standard journal or has it been turned 0.010"?

Maybe the rod is bent ....sorry, that would suck.  Also your rod-cap surfaces may not be square.