71 340 short block sat outside for last 15 years. still any good?

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340plot

340plot

the bushy bush
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i just landed a shizz load of mopar goodies, and was also invited to grab a 6/12/70 340 engine with. it is just the shortblock. it has pistons, rods, and crank. it had a oil pan, but no intake. it has sat outside for over 15 years.

i pulled a rod cap, and there is still oil on the bearings. i did not pull the mains yet, but think they still have oil on them too.

is anything able to be done to block to get rid of all the rust? how do i get the pistons out? are the rods still usable


help me out with some opinions guys/gals
 
the pic of the rod cap, that is oil on it, not rust
 

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Hey read an article on soaking a block in molasses grounds mixed with water let it soak for a couple of weeks cover in a large tub,cleaned up real well.
 
Thats a steal, picture it like this, if its in a car that is outside for 15 years. its still outside. Right? no difference here, just take it to a shop like Mop7172 said and have it rebiult, you could build a nice motor with that.
 
Hot tanking it will most likely do nothing to remove that amount of rust. A wheel-a-brater (sp?) will do a lot though. Hopefully it didn't get water in somewhere and freeze up and bust. The rods would need blasted too and re-sized with new bolts and pins and that would most likely cost quite a bit more than a new set of aftermarket rods. Pistons, beat them out with a 2-3 lb. sledge hammer and punch. Even if it had the small amount of oil on the rod bearings you see the crank will most likely be junk. My guess is you might get lucky and have a usable block once wheel-a-brated and hot tanked, if it's not cracked. Since it's a 340 it's worth a shot taking it to a machine shop and have them look it over.
 
J4R3D said:
Thats a steal, picture it like this, if its in a car that is outside for 15 years. its still outside. Right? no difference here, just take it to a shop like Mop7172 said and have it rebiult, you could build a nice motor with that.
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actually quite a difference there. If the car sat outside with the hood closed the engine would not have been exposed to the elements so it would have been in much better shape than this one.
 
fill the bores with atf and let it set for a while they will come out or if you can get hold of some KROIL penetrating oil they will come out quicker
 
Yikes!!!

That's pretty ugly. Not sure if you can still tell from the pistons, but is it a standard bore block? If it is, then you should be ok if you can get it apart. If it's already .030" over, it might be done. The cylinder walls look pretty rough.

I'd disassemble as much of the bottom end as you can, sometimes, depending on the position of all the pistons/rods, you can actually drop the crank without needing to turn it over.

Then soak all the bores in ATF, or Marvel Mystery oil, or similar. It'll take awhile, but if you can get the crank out then you should be able to drive the pistons out with a 2x4.

A machine shop might be able to get some of that cleaned up with a hot tanking, but my guess is that it'll take more work than that, so if you just drop it off it might get expensive. On the other hand, you could just have them hot tank it and then pick it back up and see if you can get it apart.

I don't think I'd even bother with trying to save the rods either, especially now that aftermarket rods aren't a whole lot more than having the stock rod redone. If all the bearings look as good as the one in the picture, the crankshaft might be salvageable.
 
it looks a little rough.....but probably salvageable.

I would just assume the rotating assembly is junk.

even if you could clean the rods up, who knows how much of that rust has adjusted the integrity as to how much strength they can handle.

I wouldnt want to rebuild the engine and find out the hard way that the rods lost there strength lol.

the crank looks like it would need a serious cleaning and probably turned.

if the cylinders have not yet been bored out than you will probably be fine with a new bore out.

as for the rust everywhere.....I have soaked rusty blocks in oil,penatrating lube and things like that and spent alot of time wire brushing and rinsing.

but you could probably pick some rust removing chemical and brush it on and then wirebrush and would make for quicker results.

I would say you have nice 340 block to start off with.

bore it and get yourself a new rotating assembly and put some goodies into it and paint it all up nice and pretty and the value of what it will be worth should easily out weigh the value of what you have invested.
 
Just put it in and run it, It looks fine to me!!!:-D The pistons look great also... LoL.... That is a lot of build up rust! I do not know if a hot tank alone can do it! Needs a definite shot blast though! NICE SCORE! I have a similar type of storage in my side yard... 3 440's 2 360's and a 318+ Hmmmmmmmmm I should hve a garage sale at the FLING!!
 
If it was outside in winter up where things freeze then take it apart (no need to be gentle) and first, you need id airless shot blasted. Then you need it magged carefully. It "should" be fine, but freeze/thaw and water in crevices can lead to cracks where you'd never see them. I've seen 427 side oiler blocks that needed cracks pinned and 8 sleeves be saved. So it's more a case of spending to make sure it's not fatally cracked before you use it. I would have grabbed it too...lol
 
You might find that every machined surface would need re machined.
Ionic ( spelt ) or some sort of rust removal is the first step for sure.
 
Hey Plot. Take it apart as far as you can yourself. Soak the cylinders as mentioned above. Dont get in any big hurry. Give it some time. Dont worry about trying to save the pistons, just try and not do any more major damage to the cylinders than is already done. Get it tore down and take it to have it cleaned and magnafluxed and check for cracks first. If that part is good then take a look at the bores. It may be worth sleeving all cylinders depending on the need and use. May not have to. Ya wont know until ya get her broke down. I use Orilleys for my investigations at their machine shop.
Small Block
 
air hammer/chisel the pistons out after pullin the crank.

you need someone to help with getting the crank out without heavily nicking the journals.

they have shot blast machines that hold the core between locking rods and then rotates it while blasting it.

the other would be to cook the block and get all the crap loose.
 
I would agree with taking it slow.... I would also buy new crank, rods, pistons as was said, the cost to refurbish the crank and rods would not save you alot if any $$$ and you would have new parts, not 40 year old parts.. Get part numbers and search the net for the best price. I know summit will price match any advertised price that is not an auction or second party. Off to the Fall Fling I go!!

Good Luck,

Brian
 
well, i have 3 340's in my cars, so i really do not need it, but maybe post it on here for 150-200 bucks.......? maybe worth it, maybe not. i just dont have a use for it, and let it go to someone that can save it.

thanks to all
 
IMO, not worth more than scrap unless it's guaranteed crack free.
 
no, the date is 6/26/70 on the block. it has trw .030 pistons in it. the crank and pistons came out within 15 minutes of playing with it. the crank is good with a polish

in virginia
 
340plot said:
no, the date is 6/26/70 on the block. it has trw .030 pistons in it. the crank and pistons came out within 15 minutes of playing with it. the crank is good with a polish

in virginia
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All this is making me feel a little better about a complete 340 I bought that sit in a car with the hood closed for 15 years!
 
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