CLcutlass

Getting back at my 455 teardown and there was some water in the 5-7 cylinders.

I am taking to a machine shop for a dip and cleaning, but what do you think of this pic. Will it have to be machined. I was hoping to stay stock pistons.


Shop is also going to give me a price on putting everything back together. I am getting them to redo the heads but I was planning on taking my time and piecing it together myself. What is the opinion of doing it yourself vs a shop. I am not a mechanic but I am a tradesman who can turn a wrench.

Coltonis

A little rusty, but a machine shop treatment should make short work of that. Between hot tanking and machining, it will end up all shiny and new. Be sure to hit that with some WD-40 right away and re-apply every so often to keep any and all moisture away from it so the rust doesn't get worse. I just recently saw some pics of a guy's engine that the pistons got too rusty and the cylinder wall cracked.

The bores will have to be measured before anyone could know for sure if they need to be bored any or just re-honed. Imho they don't look too bad. They have to be measured though since most peoples eyes can't see the difference between .001" and .002" (a dial bore gauge can see the difference).

Also, you may already know this, but the little "V" notches at the edge of the piston face indicate that you have the high compression pistons which yield about 10.1:1 if memory serves. (give or take a few - depending on bore diameter and head volume) Where as, low compression pistons have a circular notch. You probably won't be able to re-use the pistons if it needs to be bored out though.

If you want to know how an engine works, build it your self. If you don't really care, have somebody build it for you. I have a miserable need to know everything - so I'm planning to build my own engine myself.

defiant1

What is the best way to clean the rust scale off the cylinder walls? Wire wheel, scotchbrite pad, etc.?


d1

scubastever

best way is by using a cylinder hone, oil, and a slow speed drill. go up and down to create a 45 degree cross hatch pattern.

507OLDS

That will need bored.You could hone it & do file-fit rings,but now your piston to wall clearance is too great.

CLcutlass

Do you have to bore all eight...I am thinking yes.

507OLDS

Yes.

defiant1

Ok-since this topic is semi-related. I have a couple of other questions:

If the internal parts are being removed to be machined:
1) Does one need to mark the connecting rods & rod caps per cylinder locaton if they will be shot peened, reground, etc?
2) When removing the old pistons from the block, is removing them through the top of the cylinder the only method?

I am at the point now where I want to remove the crankshaft and am not certain on the best way to attack the process.

d1

Oldsmaniac

The notch on the piston tells the installer what way to face the piston and rod assembly. The notches point toward the front of the engine.

507OLDS

The pistons can only come out through the top.A lot of people like to mark the rods for the cylinder/journal they came from,but it is not absolutely neccessary unless you are doing a stock re-ring & bearing job,and no machine work.

CLcutlass

machine shop says it needs to be bored...guess my pistons are for sale