Swaping engine internals opinions, and does this look bad to you?

AyWoSch Motors

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So a while back, as some of you know, the 305 in my 86 GMC blew up.
I sorted through a bunch of options, and desided on rebuilding my original 305.
Block is still heatly, but it spun a bearing, and really damaged the crank and connecting rods, so they're junk. So I thought if I bought another 305 that was pretty much dead, but bottom end was good, and swapped the crank and rods, I could rebuild mine.
So the other day, I bought an old tired ugly looking 305 for $50. This thing is horrible. Must have 300k or more, or never had the oil changed, idk, but it looks like a BBQ pit after the 4th of July. Black sludge, carbon, yuck. Also, it was left uncovered, so 3 of the cylinders are rusted, valves are rusted, ect. Anyway, that didnt concern me too much cause I only wanted the crank. Well after flipping it over and taking the rod caps off, it's not beautiful.

My question here is how bad does this crank look to you?
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number 1 and 2 rod cap bearings.
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My first impression was JUNK, but is that normal, and I should'nt care? Tye other 6journals look okayish, but number 1 concerns me. I can grab the grooves with my nail. Should I use it, or should I look around for a better one?

And the second part to my question is, what's your opinions on swapping used engine parts from one engine to another?
Like let's say swaping an old crank and rods from one 305 to another? Is that a terrible thing to do, or perfectly acceptable? Like I know engines get a unique wear pattern, but with new rings and bearings, does it matter?

Opinions....
Thank you.

Pics of the ugly mo-fo, just for kicks.
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Flatwater

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Those crank journals are rough. You might be able to polish it out and Plastigauge it, possibly run oversize bearings. I’d opt for a trip to the mechine shop if, if time and money allows.
 

mtnmankev

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I would NOT run that crank as is.
Have it machined and get the correct undersize bearings and you're good.
 

Midnightmoon

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OK. I'm going to give you some really bad advice here. So, please ignore.

When I was a kid, I watched my father go down to Fat Martins junk yard just down the road from us, pick a used piston out of a pile of junk, check it with a micrometer, bring it home, slap new rings on it, install it in an engine, reassemble and go. You read that correctly, one used piston in an engine and it would start and run. So technically, yes.....swapping parts from one engine to another to make one whole operating piece is nothing new and will work. The bigger question is, for how long and how well? As long as you don't care if it grenades, you really aren't out much money if it fails.
 

Flatwater

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OK. I'm going to give you some really bad advice here. So, please ignore.

When I was a kid, I watched my father go down to Fat Martins junk yard just down the road from us, pick a used piston out of a pile of junk, check it with a micrometer, bring it home, slap new rings on it, install it in an engine, reassemble and go. You read that correctly, one used piston in an engine and it would start and run. So technically, yes.....swapping parts from one engine to another to make one whole operating piece is nothing new and will work. The bigger question is, for how long and how well? As long as you don't care if it grenades, you really aren't out much money if it fails.
Done it, too. Only when it hasta/gotta run and the money just ain’t there. Some of it ran a long time, some of it… not so much… lol! The joys of being broke… lol
 

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For the money that you will spend and the return you will get out of it, I would look for a rebuildable 350.
As long as you don't want over 400 hp, having a four-bolt block and a forged crank are not necessary.
If you have choices, look for some used Vortec heads, as they breathe a little better than plain old-fashioned offerings.
You need to decide if what you want is something to last the year or at least five years and plan your time and money accordingly - you can make junk last the summer no problem for about the price of a gasket set and two cases of beer....... lasting longer takes a bit more.
Personally, I do not believe in SeaFoam. Others seem to swear by it, not me.
Look through the local ads to see if any decent engines peek their noses out. If you have some patience, it may be worth it.
Note: if you do decide or not to spend a little on the engine, decide how long you will retain it AND if you want to sell it later to help finance the build you are planning for.

I can't stress this enough when I say you need TO WRITE EVERYTHING OUT AND REVIEW IT EVERY COUPLE OF DAYS UNTIL YOU ARE CERTAIN. We all know what it is like to lay in bed at night and hear the cries and whimpers of an unattended square - I do love mine, but the little beggar has no shame when it cries.
 

Turbo4whl

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OK. I'm going to give you some really bad advice here. So, please ignore.

When I was a kid, I watched my father go down to Fat Martins junk yard just down the road from us, pick a used piston out of a pile of junk, check it with a micrometer, bring it home, slap new rings on it, install it in an engine, reassemble and go. You read that correctly, one used piston in an engine and it would start and run. So technically, yes.....swapping parts from one engine to another to make one whole operating piece is nothing new and will work. The bigger question is, for how long and how well? As long as you don't care if it grenades, you really aren't out much money if it fails.

Not bad advice, just a life lesson. I did it 50 years ago on an old MGB. Replaced 1 vented piston with a wrecking yard slug. Broke one compression ring swapping from the original, so just two rings and the oil scraper. Ran it a couple years.
 

AyWoSch Motors

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For the money that you will spend and the return you will get out of it, I would look for a rebuildable 350.
As long as you don't want over 400 hp, having a four-bolt block and a forged crank are not necessary.
If you have choices, look for some used Vortec heads, as they breathe a little better than plain old-fashioned offerings.
You need to decide if what you want is something to last the year or at least five years and plan your time and money accordingly - you can make junk last the summer no problem for about the price of a gasket set and two cases of beer....... lasting longer takes a bit more.
Personally, I do not believe in SeaFoam. Others seem to swear by it, not me.
Look through the local ads to see if any decent engines peek their noses out. If you have some patience, it may be worth it.
Note: if you do decide or not to spend a little on the engine, decide how long you will retain it AND if you want to sell it later to help finance the build you are planning for.

I can't stress this enough when I say you need TO WRITE EVERYTHING OUT AND REVIEW IT EVERY COUPLE OF DAYS UNTIL YOU ARE CERTAIN. We all know what it is like to lay in bed at night and hear the cries and whimpers of an unattended square - I do love mine, but the little beggar has no shame when it cries.
I've been weighing out the options for a long while now. It died in October last year, and it's been "whimpering" at me ever since.
I could very well just go get a 350 for it, and I fact, I have 2 350s here that are in trucks I dont use much, and I could swap out easily. I could also just get a running junkyard engine, but I really didnt want to do that.
I want it to last a long while, and do it right. I dont want to just throw any old engine in it, and have it blow up in a month.
The 305 that spun the bearing is the orginal numbers matching block. That's why I sorta wanted to keep the original, and just rebuild it. I love it the way it was, had great power, ran beautifully, and I wouldnt want anything to change.
I will never sell this truck, I love it, and i want to build an engine that'll last for years to come, but i don't have tons of money to be spending on it.

When I first blew up, I originally went to oreillys, and bought a new remanufactured crate 350, i thought thatd be a good option, but that engine was garbage. I was not gonna pay over 2k for that, so I sent it back. They shouldn't even sell garbage like that.
So I thought about buying a junkyard 350, but I wouldn't be happy unless I fully rebuilt it, and thatd be quite a bit, so I thought just rebuild what you have, I'll be the cheapest option..
Machine shop isnt really an option for me. Nearest one to me, thatd maybe do it, is like 150 miles away, and I dont have that sorta money.

I just miss my truck, and really want to get it back on the road this summer.


And I'm not looking for a power monster, just a reliable daily, that I can have a little fun in, and do some work with.
The old 305 had 350 heads, a heavier comp cams cam, an eddy performer intake, and an AVS2 650 on it.
It was a sweet truck. Not a muscle machine, but fun.
 
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AyWoSch Motors

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Im gunna jump up n be the first to say it before all others get here.... BIG BLOCK IT!!!
No, I'm never big block swaping that truck.
I love me a big block, dont get me wrong, have 4 of the things, but that truck is perfect with a small block.


And yeah, boat anchor, no kidding. That's all it good for. That and target practice lol.
 

AyWoSch Motors

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Okay, so my thoughts were this:
If I'm gonna keep the 305, its going be THE 305. Keep the number matching for originality and value standpoint. If I'm going to change the engine, its going to be a small block, no V6, no straight 6, no big block, no LS, no diesel. And if its gonna be a small block, its going to ne a 350. I don't want another 305, I dont want a 400, 327s are impossible, 383 too costly.

I want an easy swap, no modifications or extra things. Its gonna stay simple and carburated, no TBI, no EFI.

Thats my criteria. If you have any suggestions for what I should do from here, help is wanted. Weather that be cheap way to rebuild what I have, or cheap option for a good 350 swap.
 

Flatwater

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My boy might have his old 305 still kicking around. You’re welcome to any usable parts if’n you’re ever in the neighborhood.
 

AyWoSch Motors

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My boy might have his old 305 still kicking around. You’re welcome to any usable parts if’n you’re ever in the neighborhood.
Well thank you sir. Very unlikely, but I'll keep that in mind. Was it running when pulled?
 

Flatwater

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Well thank you sir. Very unlikely, but I'll keep that in mind. Was it running when pulled?
Yes, it ran, but was weak. It was pulled in favor of the 400 he rebuilt. Then he ended up changing directions and not doing anything with that pickup and sold it. Last I knew, the engine is still sitting at the auto shop at the high school.
 

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