R53, 2002, 245K, burns oil by the gallon which I know to be rings, and sudden power loss. Barely limped home. Did compression test and got 125ish psi on 2 and 3, but zero on 1 and 4. Cam sprocket jumped the chain? I can't think of any other reason to have two cylinders at zero and two with some compression. Unless valves simultaneously failed, or simultaneous holed pistons! Dang, and I replaced the head 25K ago. (should have done the oil rings then). I'll pull the valve cover. Any leads on R53 short blocks? Rebuilt engines? I'm in the mid Atlantic region.
thanks!

BURNT EXHAUST VALVES ON BOTH CYLINDERS, HAPPENED AT THE SAME TIME!

 

I had no choice but to pull the head. I was pretty surprised to find a burnt valve in both Cyl 1 and 4. I'm thinking a chunk of one valve caused the damage to the other. My oil rings are shot so I have a lot of carbon on the exhaust valves. I suspect that may have helped fail the valves as it would cause uneven heating.

 

What’s the action plan from here?

 

Good question. I know the oil rings are shot, so I'm considering re-ringing the pistons while the block is still in place. Then replace all the exhaust valves as my head only has about 55K on it and the cam lobes look really good. No pitting like my first 220K old head. The car had 245K on it, so the bottom end is probably on it's way out, but then again, 300K and beyond happens all the time. Or I try to find a complete engine on eBay....or maybe locally. I messaged ModMini and he recommends a used engine, so there's that. I love the car. For a 2002, it looks brand new.

 

Solid. I like the idea of finding a low mileage engine

 

Lots of 100K ish engines out there on LKQ in my area. They seem to be everywhere in the US, so a good place to start. At least you know the mileage and there's a guarantee. '02-'06 SC engines are interchangable.