I'm looking on Amayama for a gasket kit and the overhaul vs grind kit is less expensive. Doesn't make sense - apparently they're both Toyota. From what I know Amayama is all genuine parts, right? Based on other parts, they might be Daihatsu parts (still Toyota, but "cheaper") - but it's not stated there. Rebuild videos often have Felt Pro - are those better than OEM? What is the "SUBS" package supposed to offer? It looks the same as the first one. I read that some take the head to a machine shop for a valve job and to get the head's mating surface checked. Is this really necessary? In other videos, I saw the mechanic scrape the old gasket sealer with an olfa blade, sand with a very high grit to make sure the surface is clean and that's it. I'm at 237k km (147k mi). I want to do a proactive overhaul/cleaning just to make sure everything is in good shape; 2012 3rd gen. Trying to extend this car's life a few more years. So, water a pump change, spark plugs, egr cleaning etc going down Nuts N Bolt's list all is in order. I suppose that should take care of it, right?
It's best to go with Toyota, with your vin, you know you'll get the correct parts. Just get the FULL head gasket kit. I scrap off the head, and block, with a razor blade. I just don't gouge it. Using super fine sand paper without pressure too hard would be okay. They you need a metal straight edge, one you KNOW is perfectly straight, lay it across the head from end to end and shine a flashlight on one side and look on the other side. You shouldn't see light except where the valve are in the head, obviously. But between you should NOT see light. You also want to place it around the head to make sure it's flat. If you see light, the head is likely warped. Machine shop time. If not, it's not warped. You can place the head, matting surface down, on a flat table. Then spray WD40 into each intake and exhaust port. Spray enough to cover each valve. Let it sit for 15-20 minutes. Then carefully lift the head. You could put rags in the port, then you can flip it over and check the valves carefully to see if any are leaking. If you see don't see any WD40 leaking through, the valve/seats are sealing correctly. If you see ANY fluid, then you can use valve grinding compound to seat them in. It's what I did with mine as I had just a little seepage on one valve. I wasn't really sure if it was leaking. 84,700 + miles and no issues with mine. Or you could just take it to the machine shop and let them check everything.
