Do's and Donts of refreshing a used short block.

[Afizzle]

While the new motor is out on a stand, what all should I do to refresh it? It's got 97k original miles on a virgin 97, as in no mods. I'm thinking rings for sure. Bearings? If they're fine, should I leave them alone? What else? Thanks in advance.

 

[1G Eclipse94928]

While the new motor is out on a stand, what all should I do to refresh it? It's got 97k original miles on a virgin 97, as in no mods. I'm thinking rings for sure. Bearings? If they're fine, should I leave them alone? What else? Thanks in advance.

arp hardware?

 

[crimsondragon]

If you're replacing piston rings, you'll need to hone the cylinders. That requires a full teardown. Do a compression check to gauge what needs to be done. If the rings seal fine, I'd leave it alone. I'd replace the bearings and check the clearances. If the valves leak during a compression check, I'd reseat the valves. Any other signs of oil leaks, I'd repair it while it's out.

 

[crash89]

If you're replacing piston rings, you'll need to hone the cylinders. That requires a full teardown. Do a compression check to gauge what needs to be done. If the rings seal fine, I'd leave it alone. I'd replace the bearings and check the clearances. If the valves leak during a compression check, I'd reseat the valves. Any other signs of oil leaks, I'd repair it while it's out.

Be kind of hard now, he said the engines already on a stand.

How many miles were on the engine? Was it smoking bad? Leaking oil bad? I really see no reason to even do any of this if any of those questions werent met. Sure if its smoking, rings would be your best choice. However that does require machining. If you're tearing the engine all the way down then you might as well just get new bearings anyways.

If its just leaking a full gasket fit to freshen everything up will be just fine. Thats what I did to my unknown mile stock 7 bolt. And Im throwing all kinds of abuse at it and its taking it like a champ. If you dont HAVE to tear it all the way down, dont. Theres really no need. My .02

 

[95DsManiac]

What's fine is fine and leave, what's not needs changing and change it. What are you trying to do with your car? Goals, this is a really blan question.

Anthony B.

 

[Afizzle]

It came right out of my buddies runnin and driving car with about 100k miles on it. Never been modded or anything.

How should I go about doing the bearings? What bearings would you guys recommend? If I pull the rod caps is it common practice to go in with new rod bolts or just re tq the old ones to spec?

 

[1G Eclipse94928]

It came right out of my buddies runnin and driving car with about 100k miles on it. Never been modded or anything.

How should I go about doing the bearings? What bearings would you guys recommend? If I pull the rod caps is it common practice to go in with new rod bolts or just re tq the old ones to spec?

ARP HARDWARE!
And if you refresh it now, the engine will last longer, but if machine work will cost you a lot locally then just do what you can.

 

[Insane20]

If you pull the rod caps to replace bearings I would also replace bolts. Why chance it. correct me if im wrong, but I though when you did new bearings you had to get the crank resurfaced. I could be wrong, but that's what I was all ways told.

 

[95DsManiac]

If your trying to save money then I would do:

ACL main and rod bearings, arp rod bolts, arp main bolts, polish the crank, oem piston rings.

Also before buying the rings and bearings, I would check the cylinders and mic the journals on the crank. If it needs to be turned you will need different size bearings. If the pistons are far of from one another you will need new pistons. Take them to a machine shop and they should tell you for free what it needs, or else that's how I did it when I worked at a machine shop. There's a lot you can do to the engine while it's out.

It just all up to you. How long you want it to last. What kind of power is going to be seeing be it now or in the future. Tell us a little more about it. We know it came out your friends car, but what is it going into, what are your plans for the car it's going into??

Anthony B.

 

[crimsondragon]

Be kind of hard now, he said the engines already on a stand.

There are ways to do a compression check on a motor without use of a starter. You pump the cylinder full of air using an adapter at the spark plug, then you physically rotate the crank back and forth to generate a reading. The pressure in the cylinder should closely match what's at the regulator. This is how we do it on piston aircraft because you definitely don't want to crank it over when you're near the propeller. It'll take the top off and then some.
This method also allows you to check where it's leaking from exactly. Think of it as a boost leak test but for the cylinders. You can pinpoint where the air is leaking out of.

 

[Afizzle]

The new motor is going in my car with all mods in my profile except I'm getting rid of the nitrous for Now.

My plans now are to pick up this block and do all of the timing belt components and headgasket along with cam seals and water pump. I dot think I can just do piston rings without having to hone and bore the block which will lead to a complete rebuild. Thin I'm just going to leave it alone and swap it in.. Guy said it didn't smoke and has never seen over 12 psi. He's a fried of mine so it rust him.

I'm getting the block and a new timing belt for 200$. All I need is my timing kit from extremepsi and a HG, either OEM or fel pro. Also need the intake and exhaust mani and I'm pretty much good to go. I'm going to take a day to wire tuck and take the black crap off the firewall. What all can be deleted from the firewall?

A built motor would be a dream but for now I need the car back on the streets.