I have a '76 XJ6C that spun a big end bearing on cylinder #1. I was hoping to just work that but one cylinder bore is out of spec by .0015 so I guess I need to bore the block to .020 over. Question: this has HS-8 carbs. Since I will need new pistons with an oversize bore, should I go to 9:1 compression? I still have a BW-65 automatic so does the extra power even matter? Should that slight out of spec cylinder be ignored to save $800?

thanks

Submitted by coventryclassi… on Thu, 01/30/2014 - 12:27

Richard, you do know the engine is sleeved. You can replace the sleeve & bore to fit. Make sure you remove all the alen plugs from the crank & clean the oil galleys if you have it machined. Check the pressure relief valve in the oil filter housing.
Cheers Tom

Submitted by NE40-44737 on Wed, 01/29/2014 - 08:36

Thank you all for your advice. I too am worried what went wrong. The car had not run for 12+ years, all checked out, several shake down runs, then a hard drive at 90 mph on a hot day. Oil pressure slowly went to zero and then engine gently stalled at speed. Oil pump checked out, sump was clean, brass foil in filter and elsewhere (big end bearing extruded around crank pin sides to create foil). Plan to magna flux and CLEAN all oil ways, check rod for round and fatigue, replace rod bolts, turn crank down 0.020 on rod pins & main bearings, new bearings everywhere, line bore, hone bores and rebalance lower end. Sound right?