Engine rebuild help

[slinkmerc]

Hello everyone I have a 97 420A and I need to rebuild the engine. It still runs but the piston rings in the #1 cylinder are shot. I was wondering if I bought a rebuild kit from say mizumo auto on flea bay would that be a good idea or no? Also do I need to machine the block and/or the head? Do I need to rebore the cylinders? Get oversized pistons?. I've never rebuilt an engine but I will be taking an engine rebuilding class, so before I take the class I would just like to know before hand from people who have done this what I'll need to what I'll need for the rebuild etc... All help is welcome please help me get this car back to tip top shape.

I was thinking of replacing the rings, main bearings, rod bearings, maybe new valves and lifters. Would I need new cams for the new lifters and valves or could I re use the cams?

 

[BogusSVO]

You have no idea what you need till the engine is apart and inspected.

About the only parts you can buy at this point is gaskets and timing.

Why replace the valves? They bent? no... Then no need to replace them , unless you go oversized.

As far as machining, untill the engine is apart, cleaned, and the bores mic'ed, and the crank spec'ed out. No telling.

 

[WES_393]

Without tearing down the engine and inspecting everything, it's nearly impossible to tell exactly what work needs to be done. For new rings you should at the very least get the cylinders honed. However, if you have a broken ring or damaged piston, it's entirely possible that the cylinders need to be bored. And it's also important to figure out why the engine failed in the first place so you don't cause the same damage to the new engine. Same with the head, you won't know exactly what's good or bad until it's removed and inspected. If the valves are good you could simply have them cleaned up and re-seated.

As for bearings, this is one of those times where you might as well go all out. I wouldn't just slap new bearings on an untouched crank and rods. It would be best to have the crank thoroughly cleaned, inspected, and polished/cut if needed. Same with the rods. Get them cleaned, inspected, and reconditioned if needed.

In a nut shell: Tear it down, figure out the cause of failure, have reusable parts inspected/reconditioned, replace unusable parts with new parts, and reassemble. If your not comfortable assembling the head or block, most knowledgeable machine shops can accurately assemble them for you.

Edit- Bogus beat me too it.

 

[slinkmerc]

Ok thank you, you two, what would cause the piston rings to go bad in only one cylinder? Ok so I'll re use the valves thanks bogus.
The engine still runs if that matters.