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I'm offered a used Chevy small block engine for $500. It runs fine, mechanic checked it out, owner wants a big block and needs to sell the small block.

Good price? Comparison stories welcome
 

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A lot more info is needed about this motor to make any kind of good judgement. Size, year, accessories, modifications, miles??? I personally would normally not pay $500 for a run-of-the-mill running SB Chevy. If you shop around enough you could likely get an entire car for that.
 

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I am glad that you posted this, as I am in the same situation in that I am looking for a SB chevy for my project. I see these all the time on Craigslist for similar prices, so it may be competitive price for a starting point. Then comes the decision to rebuild or not so YOU know if it is good before putting in the car.
 

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My recommendation would be to check everything you can within your abilities. Years ago I bought a supposedly running engine that was pulled and put on a stand. The owner told me it was an original 4 bolt standard bore 350. So I took this at face value and handed over my 180 bucks then took it home and tore it all down. That's when I found out the bad... 2 bolt block junk heads and .040 overbore. I don't believe anything I hear from anybody with out taking a look for myself now... If that engine is in the car running you can always test drive it. But I would also do a compression test and if you find a low cylinder or two possibly a leakdown test as well. It's always buyer beware and I never go on what the seller says.
 

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So I can understand that it is a buyer beware situation and after getting Title to the car sorted out I have thicker skin to the "stories" of just how great any of the used parts are. Can you give some suggetions for what can be checked out on an engine that is out of the car? I have seen a engine code de-coder on a Nova site, and have researched what would have been available for the time period, but I do not think that a seller will let me open the engine before buying? I have heard that if you can manually turn the engine by somehow connecting to the flywheel (?) and if it turns it is a good thing, but I have never done this so I do not know if this is true or how.
 

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If you can easily turn a V8 engine over by hand it is worn out or something else is wrong. There is a theoretical minimum torque value an entire V8 reciprocating assembly should require to turn over assembled, and though I do not remember the value, it is a lot. Now if the plugs are out and the accessories and fan are still attached, you can often cinch the belts and turn the motor over CAREFULLY by the fan. There is also a tool you can buy that is for turning flex plates / fly wheels that could assist here. However if the motor has no oil and has not run in a long time you run the risk of damaging things such as the bearings.

If you cannot hear it run and are not allowed to take off the pan, valve covers or pull spark plugs it is probably not worth dealing with :no: If you are allowed to take some things off it then comes down to what tools and knowledge you have. Are you able to measure bores, the skirts of pistons, piston-to-bore clearance, cam lift and duration, rocker arm ratio, crank end-play, connecting rod end play, etc.? Everything could visually look fine bought the motor have a .060 over bore or tons of crank end-play. My buddy bought a complete, running motor from a "trusted" source and it sucked a valve within a few months of normal driving. Something was wrong in the valve train component match-up that only measuring things out would have found, and maybe not even then.

Used engines are always a risk unless you can run and drive them or they are coming from a very trusted source.
 

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Options then?

Thanks to all for the information. There is a lot of good suggestions here. So are there any just walk away signs that newbie should keep in mind? For example if they do not know how many miles, how long it has sat, nothing to prevent stuff from getting inside, missing parts, etc.

Are there any rules of thumb that something is going to be a lot of work to fix? Like the "if it turns too easy" comment above. Having never taken apart an engine, I kind of expect that I will have to do some inspection / repair / replacement on any engine that I buy, but am nervous to find that I may buy a real heap and not be able to fix.
 

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engines

Best bet is to hear something running at least gives a bit of info on it but to buy one that has sat and not know the person a big chance. Look around for one running first. Any speed parts on it to help value, alum intake/Edel or Holley carb stuff like that.
 

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To be 100% honest it is probably in your best interest not to buy a used engine that you cannot see run since you are lacking experience with motors and their internals. There are simply too many variables that can go wrong with motors, many of which are costly.

If you have the money and the time here is what I would recommend. Go buy a used SB Chevy for as cheap as you can find (like $50). It is fine if the motor is worn out or even damaged. Take the motor home, get a good SB Chevy rebuild book and take the thing apart! Learn by doing. You will need to buy a few special tools but it will be worth it. Back in the day any core motors that would end up in the high school auto shop I would take apart and try to figure out what was wrong with them. I got to take apart small and big blocks from the Big Three and some other random stuff. It was invaluable experience and fun as well. If you do not have the space or money, go to a junkyard that allows you to pull parts and take an engine apart there. Finally if your local junior college has an auto tech program, see if they have engine classes. Mine did and they were awesome. Bored blocks, surfaced heads, valve jobs, all kinds of cool stuff. Worth every penny.
 

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South2bay

That is really good advice, thank you. I will look into this. Winter is coming and I can use the time to learn more about engines.
 
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