Motor ?
Thread Starter
Intermediate
Joined: Jun 2006
Posts: 44
Likes: 0
Motor ?
As previously mentioned, I purchased a 81 with a L48 motor that supposedly has been gone through, PO allegedly installed new cam, crank, intake, timing chain etc. I've had the car for almost 3 years, not running, and no telling how long it has sat with PO. OK, I tried turning the motor by hand a few weeks ago and couldn't get it to budge. I pulled the motor because I wanted to check few things anyway. I got the motor on a stand, pulled the plugs and still not able to turn, I put diesel, then motor oil and then marvel mystery oil in the cylinders and let it set for a week but still no go. I pulled the oil pan and checked from the back side, It appears the cam is new but crank is original, everything looks fine from here. I decided to pull one of the heads today and found water, antifreeze in 2 cylinders. Cylinder walls look good but a little rust built up around the rings which is probably why its not turning. SO, I'm going to take the heads to a shop and have them redone, pull the crank, cam pistons etc from the block and have it cleaned and checked. That will probably run anywhere between 3-400 bux. If pistons, rings etc look good, should I reuse them? I do not have any idea how many miles are on these but they all look good with no scars etc on pistons. What would you guys do?
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,063
From: altered state
St. Jude Donor '05
Hard to say without seeing
Your machinist could probably give you a good recommendation
Is it going to stay fairly stock? Any plans for later meaning you may want more compression, better heads etc or just a budget get it running deal?
Your machinist could probably give you a good recommendation
Is it going to stay fairly stock? Any plans for later meaning you may want more compression, better heads etc or just a budget get it running deal?
Melting Slicks
Joined: Dec 2009
Posts: 3,233
Likes: 657
From: Thunder Bay
I would do a complete rebuild on the motor, but if that's not in the budget, you can get away with a lot less. If the cylinders are straight (no taper) you can hone them to get a decent finish. Pistons can be cleaned up. New rings and bearings. Polish the crank. Its a small block Chevy. They're bulletproof. I've seen them run with a lot worse.
Burning Brakes
Joined: Apr 2008
Posts: 1,222
Likes: 93
From: shelbyville West Michigan
I would not reuse rust used rings. you will need to hone the cylinders at a minimum, so best case is honing, reuse the pistons with new rings. you could get by with the bearings, but they are not expensive, so I would replace them since you've got to take the rods off anyway. best case is they mic out to spec and you can use std. bearing replacements. you'll want to do the front and rear seals while you are there, but you can do that without taking the crank out if you are careful.
worst case is boring, new pistons/rings, turn the crank, new oversized bearings...can all be done one step at a time on a budget in the home garage if you have tools and a good machine shop willing to help.
worst case is boring, new pistons/rings, turn the crank, new oversized bearings...can all be done one step at a time on a budget in the home garage if you have tools and a good machine shop willing to help.
