I have been working on a toyota 20r engine that has been sitting in my backyard for 20 years. The reason why it is in my backyard, is that my dad has fried it and blew the front seal and head gasket from using the wrong type of oil. I have discovered that the only damage done to the engine from it was to the bearings. Since my dad parked it in the backyard, water has flowed into two of the four cylinders, rusting it badly, making it extremely hard to remove the pistons. I managed to remove three of the four, but the fourth one is cemented there with rust.
The technique that I have been using to remove the pistons was I placed a block of wood on top of the piston, hit it hard down into the cylinder with a 20 pound hammer, smooth the rust off the cylinder walls with emery cloth, and then knocking it out thru the top.
Anyway, can anybody think of any better, easier methods for removing pistons from rusty cylinders? How much rust is too much rust, to where I would need to have a machinist bore it out? I dont want to bore it out . . . it would not be worth the value of the engine. I am taking the crankshaft to a machinist to be inspected next week, and the block also, if I can take the piston out.
By the way, be sure and pay attention to the fact that I did NOT say that I remove the pistons thorough the bottom, but through the top. I know, I need to make it clearer. I tap the pistons DOWN, and I remove the rust from the walls, with emery cloth, so that I then can slide it up and out. but who cares.
You can soak the wall with PB Blaster until they free up a bit.
Surely you are not planning on re-using those pistons, so if one wont come out, use a chisel and bust it out.
The block will need machining, you could let the machine shope remove the pistons for you.
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wow, you dont remove pistons through the block they are intalled from the top and if you diconect the rods they will remove from the top so much easier. you may have damaged the block by removing them that way,
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im a tech
you will have to have the block machined.. new rings and seals, or oil will bypass the cylinder walls.. this "technique" of removing the pistons will scar the cylinder walls it will need machined.
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Mechanic 27 years but who’s counting.
You can soak the wall with PB Blaster until they free up a bit.
Surely you are not planning on re-using those pistons, so if one wont come out, use a chisel and bust it out.
The block will need machining, you could let the machine shope remove the pistons for you.
References :