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Discussion Starter #1 (Edited)
I performed this task on my own car, and this is only a reference for those wanting to know how I did it. I assume no responsibility or advocate success if you decide to recreate this process of your own free will. These repairs should be performed by skilled professionals and per their training.

This write-up begins after removal of oil pan, and is based on work performed on a 3800 SII engine in a 99GTP. Although I worked on this by myself, a friend and a 6-pak are always welcome additions to your tools.

Tools
2 jackstands
clear eye protection (while working under car)
Box full of Latex gloves (to handle new bearings)
Lube
3/8 to 1/4 drive adaptor
8mm deep socket (oil pickup bolts)
24mm socket (crank bolt)
6 - 12" extension (reach rod bolts)
Vise grips
Torque wrench
New rod bolts if stock (torque to yeild)


Prep
Hit the parking brake. Jack up the car and use jackstands underneath. Ideally you'd have a jackstand on each side with both front wheels off the ground for better room to work. Shore up the back tires for safety. Then place the car in Neutral. Remove passenger side tire for access to turning the crank bolt. It's been suggested to lightly wipe down the new bearings with a scotchbrite pad to clean them and it slightly creates very small scratches that won't gouge the crank, but will aid in letting oil sneak in for better lubing.

If you have not already done so, you can remove the oil pickup tube for
better access. I removed and reinstalled mine so not sure if you can do it with the pickup installed. Gasket is required for oil pickup reinstallation.

Position the crank
Starting with cylinders 1&2, rods closest to the balancer.
Use a breaker bar, or big ratchet to turn the crank over so that the bolts for the two rods you are working on are at the lowest point, and are accessible for removal with a ratchet and extension, but don't remove yet.

I reached over and turned the crank from below the car, or you can have a friend turn for you, and warn him to slow and stop once you get it where you need it. Turning the crank will be hard since you are fighting and compressing air trapped in the cylinders. You can remove all spark plugs and leave them out to let the air escape it you want it a bit easier. Do one bearing at a time so you do NOT mix-up the rod caps. Also make note of the direction of the caps so they don't get installed backwards. Some rods & their caps have identifying marks so you don't install them backwards, if not, use a piece of tape or something to identify which side of the cap faces towards the front of the car. Improper installation will lead to engine failure!

Now slowly turn the crank bolt counterclockwise (loosening direction). You want to push the rod and piston up and get the cap closer to the block, but stop where there is still enough room to allow your extension and socket to access both bolts without the block's skirt blocking access. This new placement will allow the crank journal to later swing down and away from the rod while leaving the rod in place.
sidenote:
Why counterclockwise? Because if your crank bolt is not tight enough, it may loosen and not spin the crank. If this happens, no problem, your assembly is still intact and you can proceed to tighten down the bolt further to allow the crank to turn slightly in either direction. Put the car back in park, and tighten that bolt with a impact gun or long breaker bar. On the other hand, if you turn counterclockwise when it's time to move the crank back into position to connect the rod, and the bolt loosens, well, :banghead: You're in trouble. time to pull the engine. :icon_frow
 

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Discussion Starter #2 (Edited)
Rod cap removal
Now remove the first pair of rod bolts. Test metric & SAE sockets to make sure you use the right size depending on what rod bolts you're using, stock or ARP, so you don't strip and damage the bolts.
Place a rag over the rod cap and lock the visegrips onto the cap (biting down on the rag to not scratch the caps). Wiggle the cap off. The bottom bearing may fly off when you pull the cap free. Immediately check for matching marks on cap and rod, or mark as needed to allow correct rod cap orientation during re-installation.

Turn the crank bolt clockwise (tightening direction) slowly in the direction that will NOT push the rod and piston up, but instead will make the crank journal move down and away, separating itself from the rod. Turn only until you can clear removing and installing the new rod bearing. Do not lube the backside of the bearing or underside of the rod.
 

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Discussion Starter #3 (Edited)
Upper bearing
When new rod or main bearings are installed, or even when the used ones are reinstalled, make absolutely sure that the back of the bearing and the cap or rod base is perfectly clean and dry, any oil here will cause bearing failure. Change to new pair of clean gloves, and with new dry (un-lubed) rod bearing in hand, place it on the rod. Some bearings have an oiling hole that matches up with other oil feed holes, so watch for this on your application. Be careful not to push too hard and move the piston up in it's cylinder. Now squeeze some lube onto your glove and wipe it on the bearing and on the crank journal. Slowly turn the crank again now in direction to seat the crank journal back with the connecting rod. Using the other hand, guide the rod as needed to make sure the c-journal sits properly, and doesn't get accidentally scratched with the edge of the rod. you can use a pointy phillips screwdriver and stick it into bolt hole on the rod to help guide the rod if your fingers are too fat. Once the journal seats, you may see the rod bearing turn slightly and no longer align with the bottom of the rod, if this happens, carefully use a flathead screwdriver and push on the end that rotated out a bit to push flat and realign again.
 

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Discussion Starter #4 (Edited)
Lower bearing
New pair of clean gloves again. Install the bottom rod bearing into the rod cap. Lube the bearing, and place it back onto the journal with a rod bolt in hand. Thread the rod bolt to hold it in place, but do not tighten. Install the second bolt and alternate back and forth as you tigthten the rod bolts with maybe 4-5 turns of the ratchet before switching sides so the cap goes on fairly even. Is this necessary? I dunno, do you want to risk doing this again?
tighten snugly but don't overtighten, that is what the torque wrench is for. Follow the recommended torque settings and torque down to spec.

Viola, that's it! Now continue doing the rest one at a time. Once you finish the last rod, go back and double check the torque on all the rods since you have spun the crank around completely while getting to the last rod.
 

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Discussion Starter #5 (Edited)
Pics coming soon, I think.:hmmmm:
 

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Discussion Starter #6
.....
 

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yep, pics are coming
 

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Good info. I'll make it a sticky. But...you might want to delete the mention of imperial sockets. Imperial is british, and we don't use them here. You probably meant SAE. Also, when new rod or main bearings are installed, or even when the used ones are reinstalled, make absolutely sure that the back of the bearing and the cap or rod base is perfectly clean and dry, any oil here will cause bearing failure.
 

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Discussion Starter #9
Change made, and added your sentence about clean bearings. Thanks for bringing that up.
I've added this to the list of how to threads we have, and also added your pulley install thread. Great writeup! Looks like our list of writeups is growing. Very nice.
 

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Discussion Starter #11 (Edited)
Great reminder Bill. My bolts are ARP so that also reminds me that the stocker L67 bolts use some kind of compression sleeve in the middle of the bolt that holds it in tighter. Not sure if the stock L32 have the same thing, maybe someone can chime in and confirm? Typically I removed these stock bolts with some visegrips and a bit of pull force to get them out. I'll update the write-up. Thanks for all the suggestions guys!
 

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I started rebuilding my lower last weekend. One question i had and could not find in the book was side to side clearance on the journals or end play for the crank. My book called out a tool you need, it looks just like a feeler guage. Anyone know what amount of clearance and end play is supposed to be?

thanks
Keith
 

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Discussion Starter #13
Sorry Keith, hadn't seen this post til now and hope you got your answers as I'm not sure what these clearances are anymore. Regardless, I believe it's the plasti-guage you're looking for to check side clearances when assembling the bottom end. This however is used when installing the crank and other components as it presses up against the gauge and yields a thickness to be verified. You typically don't want to use the metal feeler gauges because of the risk of scratching any journal surfaces.
 

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The side clearance for a set of rods on any given crank journal is generally around .020-.025". This can be checked with a good old "feeler guage". Some tools never loose their usefulness..........

My question to this rod bearing r&r in chassis is.........

Was the crank miked and closely inspected for wear(gruves, heat discoloration, out of round or any irregular dimensions? And if it wasn't in excelent condition, how did you remachine it? Perhaps the most important question is what caused this need in the first place and what was the "fix" so this doesn't happen again???

Jake L.
 

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i did this trick, and guess what? #6 rod bearing scored the crank bad. so the answer is no, you cant machine the crank while in car. however if you catch the sound of a bearing going early on and replace the bearings with the engine in you can in most cases save the crank. a simple slide caliper will work for checking the crank for wear.
1 other trick for checking as to which bearing is the culprit, tape on the back side of each rod, the worn bearing one will sound almost hollow.
so yes you can change bearings while the engine is in as long as you dont get pissed and rev it to 6k with a rod knock, and kill the crank.
haha live and learn
 

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Did you figure out what caused that #6 bearing failure? Do all the other bearings look good or not? The really hard part of that job is trying to clean all the very tiny metal particles from block and especially the oil supply system. All stock oil systms do not filter 100% of oil flow(maybe at an idle at lowest pressure and volumn) so if these aren't removed the new brgs can be damaged right away! By the way, was the #6 rod and cap damaged or out of round from this failure?

Any way, it sure would be nice to know what caused the failure.

Jake L.
 

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never found out what caused the bearing failure. the rod was in good shape. the "ears" that hold the bearing in place seemed to have broke off allowing the bearing to spin freely, and chew the crank.
it was about 25 miles after i did alot of top end work,(like all the valve train and head work in sig). i wanted to see what kind of power she was know making and twisted it to 6k as soon as i let off a strange noise sounded like a belt squeel at low rpm,but from the back of the engine. i thought maybee i nicked the rear cam bearing. i did notice while i was cleaning up the block for the heads that one of the teeth on the greeny i was using fell into the intake oiling hole right above the cam, didnt think much about it, but with in about 1 hour of iddling in my drive way and trying to figure it out it made the very destinct rod knock noise. the only real pain in the ass part of replacing the bearings in car, is removing the lower engine mount so you can take of the oil pan. the bolts that hold this are in a very tight spot in the rear between the enging and tranny.
but know the car has been undrivable for about 1 year now, and its time to pull the engine. and rebuild anyway, again!!
 

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Great reminder Bill. My bolts are ARP so that also reminds me that the stocker L67 bolts use some kind of compression sleeve in the middle of the bolt that holds it in tighter. Not sure if the stock L32 have the same thing, maybe someone can chime in and confirm? Typically I removed these stock bolts with some visegrips and a bit of pull force to get them out. I'll update the write-up. Thanks for all the suggestions guys!
They are designed to stretch, that is why they are only usable once. Most people complain about TTY bolts, but when dealing with components made from dissimilar metals, they work much better than your standard bolt. TTY and bolt stretch are becoming more common and a much more precise way of measuring if a bolt is properly torqued. Hence why many race engine builders don't torque rod bolts, they measure them for final stretch length.
 

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I've got a piston that chipped twice now, first time about a year and a half ago and again Monday morning. I've got a good stock piston/rod I was thinking about dropping in until I could pick up an L32. I've got a new bearing and rod bolts to go with it. Has everyone's bearings been holding up? The car is an 00 GTP with 150K on the motor and running fine. This last chip must've torn up the valve since it's got tick to it now so I at least need a rebuilt head.
 

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Id like to change THREE things here.

ONE: I would avoid turning counter-clockwise unless you absolutely have too. For one thing, theres no way you should be able loosen the crank bolt thats ~150ft/lbs tight when it should only take ~20ft/lbs to spin a motor over.

Secondly, and most importantly you will back feed the oil out of the pump, and can loose your prime. Not something you want to do.

Last thing, having oil on the back of the bearing isnt goona hurt anything, heck when you pull the bearings out at rebuild time they are always wet anyways. The tabs hold the bearings in place and keep them from spinning. Oiling the whole bearing makes it easier to get in and wont hurt anything. NOW, THAT SAID - when building a new motor or even replacing bearings like this, IF YOU ARE plastigauging the bearings, you dont want to oil the backs as the oil takes up clearance and will give you a false reading. I have been building engines for over 20 years, I have never seen a dry bearing backside from an engine that has been run. So whether you oil it to get it in, or it gets oiled running, its not goona hurt a thing.
 
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