removing wrist pins..?
Trending Topics
09-09-2009, 11:56 PM
#9
Registered User
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.
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.
09-10-2009, 12:01 AM
#10
Registered User
) 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
09-10-2009, 02:27 PM
#13
Contributing Member
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
)
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
)
09-11-2009, 02:24 PM
#15
Contributing Member
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
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
09-14-2009, 12:40 PM
#17
Registered User
Thread Starter
Join Date: Aug 2009
Posts: 120
Likes: 0
Received 0 Likes
on
0 Posts
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?
09-14-2009, 01:31 PM
#18
Contributing Member
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
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
Last edited by iamsuperbleeder; 09-14-2009 at 01:34 PM.
09-14-2009, 05:45 PM
#19
Registered User
Thread Starter
Join Date: Aug 2009
Posts: 120
Likes: 0
Received 0 Likes
on
0 Posts
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?
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?
Last edited by 9o7yota; 09-14-2009 at 05:51 PM.
09-14-2009, 06:20 PM
#20
Registered User
Water expands when you freeze it
Which is why ice floats.
Thread
Thread Starter
Forum
Replies
Last Post
1uzRunner
84-85 Trucks & 4Runners (Build-Up Section)
63
11-10-2018 03:58 PM
LotOMiles
95.5-2004 Tacomas & 96-2002 4Runners
8
09-14-2015 11:45 PM
Rickstwowheels
Newbie Tech Section
6
09-09-2015 06:12 PM
