Im guessing these are pressure fit...

heating the pistons up in hot water... will that work? how hot...

wtf mate?

 

22re or 3vze?

 

my 22re's pushed right out

did you remove the retainer clips on each side?

 

X2

 

yeah i did..both sides...and i cant push them out...22re for sure... maybe a socket of its size and tap on it?

 

eh, maybe, IF YOU'RE CARFUL, but before I did that, I'd try boiling them in some water

 

I'd put em in the freezer... Things shrink when they're cold.
Don't believe me, get in a cold shower and look down.

 

boiling water worked...

 

used wrist pins should just slide out.. well .. atleast well used ones..

but since you're this deep into the motor I'm assuming you're replacing the wrist pin bushings and the wrist pins.

so.. to save yourself further questions.. at this step you take the new pistons.. pins, bushings, (used rods with used bushings).. to the machine shop to have them assemble it.

 

True statement. And True for metal to and as far as I know any other material (i dont know, maybe something actually does expand when cooled? ) But interestly enough when you heat something, it seems to come apart a lot easier.

I'm not being sarcastic.. im actually curious why heat which causes expansion actually helps dislodge metal. Only thing i can think of is the metal becomes more maluable... or soft.. there for the same can be said for the metal surrounding the object (in this case..the bushings surrounding the pin) ... in which case... the bushings become larger, the pin as well.. and one or the other with a good smack.. becomes smaller.. ie compresses..

I'm finding this visualization really hard to describe. argh

 

nah. no machine shops. ill do it myself haha.. just replacing the pin bushings.. shouldnt be too difficult.

 

You heat aluminum pistons because they EXPAND at a much greater rate than the STEEL wrist pins.

 

you know you have to have the new bushings honed to fit the pins right?


I pressed my bushings into the rods myself, and then took the rods and wrist pins to the machine shop that did my block to have them machined


pressed in myself:






and had to have the bushings honed to get the pins threw (same rods, just glass-bead'ed clean )

 

not using new pins...still need to get them machined?

 

yep

even with the old pins, the new wrist pin bushings need to be machined to fit the old pins


it's a little easier when you're replacing the pins too, cause you can bring all of the rods and bushings to the machinist, and just one wrist pin, and he can do them all based off of that one pin, since they're all new and will be the same size and specs

but using the old pins, you need to bring EACH pin to the shop with the rods so that the machinist can hone each individual one to fit, and then BE SPECIFICALLY SURE NOT TO MIX AND MATCH THEM UP AFTER THE FACT



I just assumed pay the $50 or whataver it was from engnbldr for a whole new set of OEM style pistons that came with new pins and lock retainers, and all was good

 

so lets say the pins go back into the new bushings... what are the chances of that being bad to just go with it if it fits ?

 

bump... sorry guys i got my pistons cleaned yesterday so the pin bushings and rod bearings are today..possibly stabbing them into the jugs as well.. i really need to know if i HAVE to machine the bushings.. i really dont have the money nor the time to do it.... if the wrist pins fit.. how bad is it if i havnt machined them?

 

well, I HIGHLY doubt the pins are going to fit in the new bushings without honing

POSSIBLY before they're pressed into the rod, you MIGHT be able to squish them on, but once you press them into the rods, they are going to compress inwards a little

I'm not 100% sure about the clearance specs between the pin and bushing, but there is movement between the pin and bushing; the pin can pivot on both the piston AND the rod, thus the reason for the lock/retainer clips on each side of the piston to keep the pin in place

now, let's just say the pin DOES happen to slide in after pressing the bushings in, there's maybe a 1 in a 100000 chance the clearances will be right were they need to be; it might be too tight of a fit, which will cause a lack of oil, which will eventually cause the bushing to wear abnormally and oblong the inner diameter, and cause premature failure of either the bushing and/or pin; on the opposite side, if it's too loose of a fit, then obviously there will be too much movement, and the piston and rod will have that microsecond of "slack" at the end of every stroke, and the pin is basically going to beat the bushing to death eventually, which could in turn cause bushing, pin, and even rod or piston failure

I can't imagine how much just a simple hone on the bushing would be; when I had my rods and pistons at the machine shop, they just checked off "R&R Rod/Piston", and the charge for all 4 was $20, and that was glass beading the rods, re-honing the larger crank ends, AND honing those bushing into spec per the new pins


Basically, you can use your old pins, but everything I've ever heard, read, or seen, states that you HAVE to have those bushings honed to fit, or it's just not going to work

 

okay. thanks dude thats what i needed to know...

just a thought... say i dont machine them, cuz they fit on the pins right now. with lube im sure i could get them in through the piston.. metal wears...so either the pin or the bushing will wear...now... wouldnt that eventually cause there to be enough room for oil clearance?

 

Water expands when you freeze it
Which is why ice floats.