Hello all,
I have an owned since new 2006 Honda Accord 2.4L (K24A8) sedan 180,000 highway mi., always Mobil 1 synthetic oil every 5-7K. Started excessive oil use around 70K, now using 2+ Qt every 500 mi. The cam chain jumped several teeth at 160k and bent 4 intake valves. Had head professional rebuilt, new seals, bent valves replaced, all valves and seats reground, head checked and machined, valve clearances set to spec. After reassembly, oil use continued, thus planned to replace piston rings (assumed stuck or poor sealing oil control rings) in the Spring. Recently while traveling on the interstate the engine lost compression on #3. Pulled head and found 1 burnt exhaust valve, not sure why (approx. 20K on head rebuild). Recently pulled pistons (removed oil pan while still in vehicle), all rings appear to be free in their grooves, oil rings are expanded slightly beyond piston surface and can see light thru drain holes in oil grooves. Cylinder walls look fine and all bore gauge dimensions are well within service limits per Honda service manual. Pistons measure within service limits as well, though one is at the lower end. Black wear area on piston skirts have mid and lower areas worn thru but some of the black remains. (see image)

I'm hoping to get another 50-100K out of the car which will be used by my 15 year old daughter. To keep the budget down, I was thinking i'll thoroughly clean the pistons and re-ring with new NPR brand rings (Honda motors can go many hundreds of thousands without rebuild). I considered replacing the pistons with reasonably priced Evergreen brand made in Taiwan. However, thought I'd stay with my orig. Honda, new Honda too pricey. I'll leave the block as-is, Honda service manual states not to hone cylinder walls unless scratched. As for the head, I'll have the engine shop replace the burnt valve. The rod bearing seem to be in good shape, I'm considering re-using these.

Does anyone have any comments or insight on my plan of action or why the motor uses so much oil? Burnt valve? Re-use rod bearings?

Any sound advice for this shade-tree mechanic would be greatly appreciated.