Best Way to Change Crank and Rod Bearings

[Blown&Injected]

BACKGROUND:
Ready to change the bearings. I need to clean up some of the journals that appear to be a bit dirty. Some of the old bearings show lots of copper and some junk seems to have stuck to the journals - nothing dug into the journals/no scoring but some polishing seems to be in order.

?
Is it advisable to unbolt the torque converter and pull the crank out with the flex plate? - engine is in the car.

It seems like it could be damn tough to get the crank back in but it also seems like it will be hard to keep everything clean after fishing some 600 grit wet sand paper over the top of the journals.

Maybe I should just un bolt all the rods and one main. Then way loosen up the the other mains to let the crank drop about a 1/2"???

Thanks for your ideas.

 

[Red Regal T]

Forget pulling the crank. I'd do the mains first. Just loosen them all. You must remove the serpentine accessory belt also. When you polish the mains, first do one side, then turn the crank 180* to do the other. Then just wipe off the journal. No problem to keep it clean unless you throw dirt at it. Then go on to the rod bearings. Just do one at a time. Pull crank throw to the lowest point as you do each rod. Remove the cap and push the piston up in the cylinder enough to remove the upper shell. Lube the bearings, install on the rod, and torque it up.

 

[Chuck Leeper]

Pull it!

A crank polish and a brg replacement in the car is a no win deal.
1. The polishing grit WILL get into the crank oil holes.
2. The rods must be supported w/ shim stock to prevent the caps from twisting when the bolts are torqued.
3. The only CORRECT way to check clearance is to use a dial bore gauge.. NOT plastigage. You can't use Plastigage cause the crank is laying down in the brg bores.
4. The work space above the ft frame crossmember is restricted, and not a good place to work on something as complex as brgs.

Pull the damn thing out, and do it the right way.. You'll be glad you did!

 

[Quick6'n'-K.C.]

i agree-

its much faster for me to pull the motor out and do everything on the stand- that way if something else is wrong, you dont have 10 hours of work started and the motor is still in the car!

just pull it and make it a weekend deal, make sure you have all the parts in your hands before you tear it apart so your not waiting on parts to be shipped in


you can put the entire motor back together on the stand and then drop it in, heads, intake,headers,starter,balancer,timing cover,oil pan ect-

BW

 

[Red Regal T]

Look, anybody can understand it's better to rebuild an entire engine with the motor out. Hell, why not give it to some major engine builder and give him a blank check. That would be better yet. This motor obvously needs to be redone at some point in time. If he replaces the bearings in the car, and checks nothing, what's the difference. He may have the use of the car for another 10,000 miles. If not, what's the big deal? What's he out, $50 and a few hours work? I'd opt for the gamble. Nothing to lose.

 

[V6 Beast]

Listen to Chuck..... It takes less than two hours to pull the motor and you will save that much time doing things correctly on a stand compared to doing things with the motor in the car.


Sully

 

[Blown&Injected]

High guys.

Yeah, I would like to put it on the stand - hell, I even built my own stand that one could park a house on. It would be great to do the things that were written about in the oil/rebuild tricks in High Tech Performance like drilling out the oil passage from the cam to the main journals etc, but as I mentioned on "the other" site:

the car is in my friends garage, if he sees me pulling the engine, he will have THE BIG ONE.[/Fred G. Sanford.]

Still, thanks for all the thoughts on my situation. I'll report back on WTH happens to my engine.

 

[Red Regal T]

Make sure you drill out the front three main bearing holes to at least 1/4". I drilled mine to 9/32". I'm also using a hi-volume oil pump and have great oil pressure. Take it from someone who actually drives his car.

 

[ITSAV6]

update?

Did it live after the bearing swap?

 

[Blown&Injected]

Engine ran fine, well, just a few pounds better on the oil pressure
So it looks like it is now cam bearing time.

The job was quick and easy - just did not fix the problem. The bearings had worn into the copper so it was not wasted, unless the probable oil loss at the cam bearings starved the new crank bearings causing damage again. We'll see.