this is a rod/main bearing from a 1987 duke, the motor wasnt knocking but it had a blown headgasket and alot of coolent in the oil, i already have a thread going about that.

the rod bearing has some visible marks but you cant feel anything, however the main bearing is smooth except where the notch is, it has a metal grove on it that you could scratch your finger nail with, its very noticable, there was also some very hard black gunk caught between the two pieces of main bearing.

im not 100% sure at this point if its worth my time to put this motor back together, cause now not only will i need rod/main bearings, but im going to need a headgasket set also, and for that much money i i can buy a whole 1991 caddy with a 4.5L PFI motor in it (pretty sure the 4.5L was swapped in to replace a bad 4.9L)

Oh, figured id mention that the crank surface had discoloration on it, it didnt feel grooved, but it didnt look polished either, just didnt look right.

anyway here's the picture.



in the second picture, the black specs are easy to feel with your finger.

[This message has been edited by m0sh_man (edited 11-23-2007).]

They look normal nothing wrong with that wear

Pics are not to clear, can't tell how deep the scratches are but looks like normal wear from what you can see.

look normal to me. these are bad bearings

so i should be able to put these bearings back in, torque to spec and be fine for a while?

matthew

if you have the engine apart that fat, just get it rebuilt

Doesnt matter how they look. Once coolant is impreganted in the material, they're shot. Clean the block well & install new bearings & plasti-gauge them.

quote Originally posted by PURPLE REIGN: plasti-gauge them.

You can clean them and put them back in the block. But do plasti-gauge them to see where you stand like PURPLE REIGN said. That will take the guess work out of the install. Its cheap and easy. Gauge them dry without oil or lube. If all is within specs, then remove the crank, lube it all up and re install everything.
Joe

[This message has been edited by josef644 (edited 11-23-2007).]

Don't put the old bearings back in!

But you need to what size your rods and mains are on your crankshaft. They might already be undersized because of a previous rebuild. You need to mic the main and rod bearings. If they are standard and the surfaces look good you can put new manis and rod bearings in that match your bearing sizes.

You also need to mic the cylendars. Top, center and bottom to see what size the bore is and buy rings accordingly.

The last engine i rebuilt was a 90 SHO engine with 130K all bearings were in spec as well as cylendars, with NO RING GROOVE, put standard bearings and rings in. Took the head apart and cleaned the valves, (removed carbon), hand lapped them in and it ran like a new engine.

If you havent done this kind of work before you need to do some reading to avoid problems. And wasting money.

Good Luck

A set of main bearings is about $35. Why would you even consider not replacing them after taking the engine far enough apart to get them out?

quote Originally posted by Formula88: A set of main bearings is about $35. Why would you even consider not replacing them after taking the engine far enough apart to get them out?

because im trying to justify fixing the motor.

after long thought of reliabilty and everything im just going to leave the car on my back porch for now and try to find a 4.X series PFI from a caddy, or a 3800 series II even if its n/a it should work out fine.

i figured up the oil pan gasket, headgasket, intake, valve cover, exhaust gasket, push rods (current ones are very bad) getting the head tanked and cleaned, then headbolts and other stuff, it would be $150-200 to fix the motor,and thats without new rings, and polishing the crank or anything, it just isnt worth my time for a motor with less than 100hp, im very capable of a swap and a high mileage motor doesnt scare me at all if its running and cheap enough.

thanks for your time guys, but this 88 coupe is going to be seeing a engine swap in its future, its my first automatic fiero that will be getting a swap so ill see what i can do.

ive got a friend with a stock 2.8L i can have, its possible i may just throw it in, but even the 2.8L's feel weak and poor after driving my other fiero's.

i guess ill see what happens.

matthew