DONR

I decided to go ahead and do a little maintenance on my 66.
I have the oil pan off. Not too hard with the tie rod linkage dropped.
The question is should I go ahead and replace my Main bearings and rod bearings while I have the pan off. I did buy the one piece felpro pan gasket to go back with along with the felpro 2 piece main bearing seal.
I do not know a lot of history about the motor, but it now keeps good oil pressure, but the main bearing does have some grooves in it I notice when I took the rear main cap off.
I am going to get the starter rebuilt while it is off.
Thanks for any advice that will make this job go smoother.

Don

cardo0

I have to ask why you even took the oil pan off?? How much extra work do you want to make for yourself? Grooves in the brg usually mean scratches on the crank journal. But if you have good oil pressure and no noise from the bottom end why not just put the cap and brg back on and torque to spec w/good torque wrench? To remove crank scratches requires a polish as a minimum or regrind if bad enough. Do you do a lot of racing? I guess what im saying is if you just do a lot of cruising around and nothing really stressful to the motor you may just be headed to a full overhaul when the motor will live as is for decades.

So have i polished a crank from under the car? Yes but its a lot time on your back. FYI the Chevy Power catalog shows how to hand polish a crank before installation using 400 grit paper and a leather strap. But under the car u have to roll out the brg and thread a strip of 400 grit in and around the journal then you need to rotate the crank every so many strokes to get an even polish. Do you really want to go there. Just to put around in your convertible my advice is dont fix anything that aint broke.

Hope this helps and good luck. Let us know how you proceed - it helps us all.

GTOguy

What cardo0 said. Put the old bearing back in and run it. Installing new bearings without machining or polishing the crank won't accomplish a thing. When it's time for an overhaul many miles and years from now, you can do the whole engine and do it all at once the right way.

DONR

CardoO and GTOguy thanks for the advice. Your plan seems like the right thing to do. Leave the old bearing in and drive it. At a later date I will pull the motor and do a complete rebuild.
Here is my ride.

GUSTO14

Don, if you can before "wrapping" it back up, take a couple of closeup pictures of the main bearing and the crank journal from a couple of different angles and post them. You may get a bit more in depth answer if the folks here can actually see what you are seeing.

Good luck... GUSTO

cardo0

Well thats a great looking corvette Don. I like your decision and hope you can enjoy it for quite a while. "While I'm at it itis" is highly contagious among corvette owners and there are plenty of now garage queens that weren't really necessary.

Drive it and have fun.

DONR

I will take a couple of pictures before closing it up.
I am thinking about taking it down to Gulf Port Miss. for Cruise the Coast event the first week in October.

Don

pop23235

Pictures and experience may help. Back in the day, the 327 HiPo when run hard could need bearing replacement. Grooves are trash, wear is fairly uniform removal of metal. As a queen or seldom driven unit, not so much need.

itsforfun

I would pull several bearing caps (keep them in order) and see if they all look the same. Any good machine shop will take a look and give you a professional opinion. The bearings are date coded- that may help.
Rather now while everything is apart, than have to do this all again later.

R66

if you are concerned about it, plastigage the rod and main bearings to see if they are with in tolerance. Ignore dirt scores. Consult your local GM manual.

It they are within tolerance, put it back together and DRIVE IT!!
Don't replace what ain't broke unless you have more money than you need, in which case, send it my way before your Vette nickels and dimes it away.