when doing piston and rings do i.......

[buildit4bill]

i have just inharited a 1993 nissan 240sx from my uncle who has taught me about the value and the improtance of driving and owning a 240sx. i have had one of my own and it got wrecked. my uncle has been building a 240. he has done alot.turbo, lowered,emanage,...... but the rings have gone bad and he has passed away in a motorcycle accident and now i will be taking care of his car for him. i need to know if i have to pull the head to get to the pistions or if i can get to them through the oil pan?

[silkk]

Sorry to hear about your uncle.

You have to unscrew the main bolts on the bottom of the crankshaft to take off the piston. I'm not sure if you can take it out from the bottom or not but others can help.

Welcome to NICO!

[MaineExport]

Sorry to hear about your uncle.

Welcome to NICO.

I haven't got much experience with KA internals, but I am pretty sure the head has to come off.

I rebuild ATV engines regularly (2-strokes blow through piston rings like mad), and the cylinder and head have to come off to remove/replace the piston. Going at it from the oil pan means the crank is in your way.

[Hijacker]

if you're doing rings, you're gonna have to tear the motor down to make it easiest.

it's easiest because you can make sure that the rings are gapped properly and when you reinstall the piston, it needs to go in from the top

[Hobie1113]

I've only worked on my SR in tearing it down but to get the pistons out...Pull the head off of the engine. Flip the engine over. Pull the oil pan off. Pull the windage tray off. Pull the main caps off. Apply light force to the studs on the rods to pop them through the cylinder.

You cannot get the pistons and rods through the bottom of the engine.- There is a crank there.- There are oil squirters there, too.



I'm currently rebuilding my SR that I just picked up Saturday.

[Hobie1113]

BTW, when you do this you're gonna want to go ahead and do as much as you can while the engine is apart.

Don't reuse the gaskets.Don't reuse the head bolts. I wouldn't reuse the main bolts either.You may want to change the timing chain, that's up to you.

[Hijacker]

in a perfect world, you would replace the head bolts every time you yanked the head, but that's not always the case. just make sure that the headbolts have no stretch in them, and you should be golden. when reinstalling them, dunk the threads in some oil so you'll get a more accurate torque reading.

[turtl631]

If you want to put in forged pistons, can you do that yourself or do you need a machine shop to do it?

[dfw240_EE]

Didn't the 91-93's come from factory with forged pistons?