Freeing up a frozen block ??

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halfafish

halfafish

Damn those rabbits, and their holes!
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I bought a "parts lot" a bit ago. Included was a frozen 273 block. Partly just to see if I could do it, I decided to see if I could get the block loose. I was able to remove the oil pan and then oil pump, but then my luck ran out. Two of the 16 rod bolts are in a location that I can't get to with a socket, crow's foot, or regular wrench. How does one get the rotating assembly loose to finish taking it apart?
 
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Evaporust...then hit piston tops with heavy rubber hammer while someone else turns crank
 
A third vote here for the Marvel Mystery Oil.
Pull the spark plugs out and load a bunch in the cylinders, put the plugs back in, and wait a few days.
Diesel fuel works pretty good too.
We used to call it giving the engine a diesel fuel enema...lol
It helps if you take the rockers off so that you aren't trying to move the valves too while you are trying to turn the crank because they are probably stuck in the guides.
After you get the engine to turn over, to get the valves to move, sometimes just a firm hit with a dead blow hammer to the top of the retainers will free them up.
If not, then use MMO and or heat will loosen them up.
Patience is a virtue here...
 
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If you do go the marvel mystery oil route and happen to leave the plugs out, beware when you finally get it to rotate. Looks like a crime scene when the fluid comes out the spark plug holes. Lay some cardboard or the like in the vicinity to help alleviate some clean up.
This potential mess applies if the heads are still on of course…
 
i wonder about white vinegar and trans fluid mixed. wv soak tends to remove rust from smaller parts. that has been shown on here. i think RRR posted something on that . i tried just wv and it worked some. i also tried it and left the parts in way too long. not pretty.
 
Love him or hate him, Uncle Tony did a video on breaking an engine loose.
He tried 4 different witches brews and I think Vinegar worked the best.
 
I’ve used trans fluid a couple times works great, a few days maybe a week and pistons slid right out, never tried marvel, but a lot of guys swear by it for a lot of things
 
Your waisting your time... Lord knows you don't need it and who wants it??.,
How much more are you expecting to get for a formerly frozen 273 block??...
You have way to many cars and trucks to be waisting time on garbage...
Your friend Jpar.... :thumbsup:
 
j par said:
Your waisting your time... Lord knows you don't need it and who wants it??.,
How much more are you expecting to get for a formerly frozen 273 block??...
You have way to many cars and trucks to be waisting time on garbage...
Your friend Jpar.... :thumbsup:
Click to expand...
Sometimes it's not the destination but the journey......
 
First, did you go ahead and pull the ones that you can reach?

I'm assuming motor is on a stand?

I've had the best luck with any kind of penetrating oil, and then using a prybar on the counterweights with mar-protection on all contact points. (FYI Excalibur, my preferred prybar, is 48").

Conversely, if it will hold water, you can wash all the oil out with brake cleaner and fill the cylinder with water (unless it's at TDC) and use the electrolysis rust remover trick. It will pull rust out of all sorts of nooks and crannies, which is what you really want because the rust is mechanically locking it in place.

ETA And I would ignore the naysayers. This is exactly the kind of project that you can learn on and if you break something....meh. Then you'll know better when you score that locked up 340 at Pick n' pull and don't want to mess it up.
 
I should have mentioned, this is a short block. I'll rotate it so one bank of pistons is up, and give those a soak before doing the same to the other side. I do have it on a stand. And yes, sir j par, this is an exercise in "how does that work". The engine is going to the scrapper when done.
 
halfafish said:
I should have mentioned, this is a short block. I'll rotate it so one bank of pistons is up, and give those a soak before doing the same to the other side. I do have it on a stand. And yes, sir j par, this is an exercise in "how does that work". The engine is going to the scrapper when done.
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You sure you don't want to wait until you're handed that numbers-matching Hemi Daytona to figure this out?
;-)
 
halfafish said:
I should have mentioned, this is a short block. I'll rotate it so one bank of pistons is up, and give those a soak before doing the same to the other side. I do have it on a stand. And yes, sir j par, this is an exercise in "how does that work". The engine is going to the scrapper when done.
Click to expand...
LOL...
 
I learned a lot as a kid from just taking thing apart. The harder it was the more fun it was. I think it is still fun to take things apart, unfortunately the wife expects me to put them back together again, nuts.

jos51700 is exactly right, this is really good practice for when you might really need it. Almost any kind of penatrating oil or liquid should do the job. It just needs to be low viscosity to actually soak into the rings. Frankly I'd start with either the cheap and easy options of gasoline or diesel fuel. But as a last resort you could always just take a chisel and break up the stuck pistons and remove them in pieces. If you were really going to save this engine, you would have to bore it out oversize so the pistons in a rusted stuck engine are useless anyway.

One other place to go for ideas on this kind of project are the tractor restoration websites. Those guys run accross this all the time, and find amazing ways to unstick the engines, and they have the harder task of saving the pistons since replacements are usually unavailable. They do have the benefit of only needing the antique tractor engine to run up to about 2,500 RPM with a compression ratio in the 5:1-6:1 range so the needed quality of the bore and pistons is much lower than a modern engine. They can sometimes still get them to run after sitting in an open field for decades.
 
Even if (big if) you get the pistons out the rings will never seal again so the engine will need a rebore and new pistons. I had a stuck Porsche engine that I couldn't free up. I ended up splitting all the cylinders with an angle grinder so I could remove the pistons and split the case. The cylinders make good pencil holders.
 
j par said:
Your waisting your time... Lord knows you don't need it and who wants it??.,
How much more are you expecting to get for a formerly frozen 273 block??...
You have way to many cars and trucks to be waisting time on garbage...
Your friend Jpar.... :thumbsup:
Click to expand...
Realist
 
MinnesotaMopar said:
I learned a lot as a kid from just taking thing apart. The harder it was the more fun it was. I think it is still fun to take things apart, unfortunately the wife expects me to put them back together again, nuts.

jos51700 is exactly right, this is really good practice for when you might really need it. Almost any kind of penatrating oil or liquid should do the job. It just needs to be low viscosity to actually soak into the rings. Frankly I'd start with either the cheap and easy options of gasoline or diesel fuel. But as a last resort you could always just take a chisel and break up the stuck pistons and remove them in pieces. If you were really going to save this engine, you would have to bore it out oversize so the pistons in a rusted stuck engine are useless anyway.

One other place to go for ideas on this kind of project are the tractor restoration websites. Those guys run accross this all the time, and find amazing ways to unstick the engines, and they have the harder task of saving the pistons since replacements are usually unavailable. They do have the benefit of only needing the antique tractor engine to run up to about 2,500 RPM with a compression ratio in the 5:1-6:1 range so the needed quality of the bore and pistons is much lower than a modern engine. They can sometimes still get them to run after sitting in an open field for decades.
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I question him "needing" this experience...
Ask him how many Big blocks small blocks and slant sixes he has there in good condition...
How much work does he have to do on the three mopars that he's currently working on? And spending time beating out old Pistons out of a motor nobody's going to use...
This is just useless procrastination of time that should be spent getting that 69 dart on the road... (His dream car....)
Your friend Jpar.... :thumbsup:
 
I’m a big fan of Kroil. It’s pricey but really works on badly rusted fasteners and parts. Apple cider vinegar is also good for removing rust.
 
j par said:
I question him "needing" this experience...
Ask him how many Big blocks small blocks and slant sixes he has there in good condition...
How much work does he have to do on the three mopars that he's currently working on? And spending time beating out old Pistons out of a motor nobody's going to use...
This is just useless procrastination of time that should be spent getting that 69 dart on the road... (His dream car....)
Your friend Jpar.... :thumbsup:
Click to expand...
I could say the same to you AND him for posting on this website.
Jus' sayin'.
 
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