I took my B16A2 block to get bored and honed, but when I got it back the main cap clearances were too small. If the crank is bolted in and torqued down, then it won't budge. There's only about 10K miles on the crank and bearings, and I got the block bored because I melted the pistons a bit, but the machine shop says they did nothing to the bearing journals.

What would cause the clearance to get smaller?

 

I know its basic but make sure the caps are in the correct positions and facing the correct direction.
Glenn

 

I think we figured it out. I went back to the shop and talked to the owner. Apparently when they bore a block they set it on a round metal bar on the main bearing journals and it will sometimes scuff them a bit, causing the bearings not to seat properly. He said most people don't notice it because they don't measure the clearances down to .0005" like the guy I'm having assemble the bottom end, and that once it gets running it takes down the high spot pretty quickly. He said we could buff it out with a very mild abrasive or a fine circular file.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by rmcdaniels &raquo;</TD></TR><TR><TD CLASS="quote">I think we figured it out. I went back to the shop and talked to the owner. Apparently when they bore a block they set it on a round metal bar on the main bearing journals and it will sometimes scuff them a bit, causing the bearings not to seat properly. He said most people don't notice it because they don't measure the clearances down to .0005" like the guy I'm having assemble the bottom end, and that once it gets running it takes down the high spot pretty quickly. He said we could buff it out with a very mild abrasive or a fine circular file.</TD></TR></TABLE>

Now thats scary..

 

We put it together and fired it up, it ran for about five seconds before it siezed. It's coming out to get line honed.

 

I know this is old, but what the f*ck? The motor seized!? Did that shop offer to fix it?

Was no one else bothered enough by this situation to comment back in April?