i ask because im looking around and i found a 350 long block with about 50,000 miles on it.

i was wondering when you would rebuild an engine.

and would you rebuild one that you buy used regardless?

 

Well thats an interesting question. Under normal circumstances 50K its just just a baby and i wouldnt even concider rebuilding it unless it was knocking or burned alot of oil. Howere you wernt the owner for the last 50k miles so you really dont know whay kinda shape its in. Now the simple answer is just rebuild it. I mean for starters when buying something like that how will you ever really know it actually has 50k on it? Even if it does have 50k miles on it though you dont know if thoes were 50 k well maintained miles or 50 k since its last oil change. You dont know the condition of the internals in terms of there could be corrotion from sitting if it was stored in an unfriendly envirnment. Again from sitting you could have dry rotted gaskets. Right now its out of the car its thie ideal time to get it back to 100% and even though more than likely it dosnt "need" a rebuild thats a bit of an assumtion to make without really knowing anything about the motor. Plus a rebuild cost is dependent on the amount of work actually needed and if its really that good it wont be too expencive. I suppose you could get by with tearing it down and checking it out but at that rate youde be basically doing a rebuild.

 

i guess what im aiming at is would it need machine work. but again i guess it would make the difference of how it was driven/stored, correct?
they said it was running find when it came out of the truck.

 

Well like i always say trust but verify. They could be telling the truth and it may have ran great but then again they may have just dumped a hunk of junk on you. Futher more lets say it had low oil pressure it may have ran fine as far as they knew but clearly it still needs attention. Now will it need machine work theres alot of things that will determin that like as you said maintenece and conditions it was stored in ect so i couldnt possably make a guess what it will actually need as far as machine work if any. The only way youll really know is to tear it down and check the clearances. Under normal circumstances a well maintained SBC at 50k should not need anything in the line of actual machineing but again you cant assume that in this case.

 

bleh, so i basically wont find out until i buy it

 

Well yes and no. Athough youll never really know for sure untill you buy it and tear it down there are things you can look for. For example ask if you can run a compression check befor hand. Check the oil (or for the absence of) see how it looks. Pull the plugs check them out and maby see if you cant get a glance at the cylinder walls. Try to get a smell of the dip stick or since its a long block im assumeing no intake manifold just get a whiff of the lifter valley chances are if it smells heavy with gas or anything funny for that matter thats genrally not a good sign. Look at the motor itself is it covered in oil indicating a possable leak or worse yet if its been cleaned up who knows if there trying to hide something. Look for sludge build up. If the oil pans off look at the bottom of the connecting rods for stamped numbers or something indicating that its had some work done at a machin shop already. And best of all just turn the motor over by hand see how freely it moves. Theres alot of little detail things you can look for that can give you an idea but again at the end of the day its a gamble unless thell offer some kind of guarenty which i kinda doubt they will.

 

oh i see. well i actually have a 350 block, fully machined.
im just looking for a long block to throw in the car so i can drive it as i build the other engine.

 

Well again it may run great and run far longer than its needed but then again it could have spun bearing meaning it wont work at all without machine work. Personally ide say if you intend to finish the motor in relitivly short order just wait and save your money because its a fair risk with little to gain. If this motor is something crazy that you dont expect to have done for a few years then it might be worth while to buy it and go through it. Nothing bad about having a spare SBC around anyways. To sum it up the only thing i would not do is just buy it and try and run it as is with the idea its only got to last 6 months because if the other motors that close to completion its not worth the time, money, and the effort and if you do expect to run it for a while, while the other motors being assembled, then the only way you can enshure that it will with any kind of confidence is to go through it.

 

yeahh i was thinking of having the car sit s i build it. i should have it done by the end of the summer. im pretty much waiting for more money to roll in.

i just wanted to drive my car again. if i drive the lumina around for too long i'll go crazy. especially during summer =(

 

Yea i hear ya on that but all the more insentive to get working on getting her back together the way its ment to be rather than a bandaid to tide you over.

 

yeahh i know, i decided to just wait and build it.
what should i do first. get the SFCs and stuff and put them in? or just save up? either way im getting the same amount of money from working.

i guess though if i save every penny the engine could go in possibly a month earlier

 

What ide do is first get the car moveing under its own power. Sub frame connectors are always a good idea on these cars but in alot of cases arnt truely "neccessary" and you can always be driveing the car while your saveing up for subframes.

 

well in that case then what about the shift kit? new radiator?

 

Well again ide do the minimum amount of work to get the car moveing under its own power. I mean it would suck to thow 2 grand into suspention stuff and audio equipment to find out you need to rebuild to trans. Now the shift kit ide say its easyest to do while the trans is out so if the trans is out of the car do it if not it wont make a difference when you go it really. The radiator if you dont have even a stock one just has to be done. If you have the stock one i would say hold off untill the cars running and moveing under its own power because that can be done at any time as theres no real advantage of doing it now or later. You may not want to really drive it if its real crazy as you dont want to overheat it but make sure the car runs and drives befor you invest in other aspects of the car. Its just one of thoes things if the car runs and drives great you can throw tons of money at it but its one of thoes things make sure you have a running and driveing car first as you never know what tomorrow will bring. It would suck to have a great chassy but due to unforseen circumstances not have the funds to get it running.

 

Have a compression tester? Do a compression test and see how all of the cylinders come out. If all are good buy it, run it, sell it...