Stuck pistons/Crank, any ideas?

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Inspector71

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I procured a 383 engine (sans head/intake) from a friend. I got the oil pan off, timing chain and all that. I removed the 5 main caps and bearings as well as the main seal bridge with no trouble. I am trying to unbolt the pistons from the bottom but cannot reach all the nuts unless I can turn the crank but it won't turn. The block is on my garage floor. I have no way to get it up to the engine stand or transport it anywhere at this time. There is some rust and the motor sat a while but the crank looks great. Any idea how to move the crank and or bust loose the pistons? I am going to look for an angled half inch wrench that might fit in the tight spaces. Any ideas will be appreciated.
 
Sounds like the rings are rusted to the cylinder walls. There's a product called PBlaster at most any auto parts store. Get several cans and soak the cylinders. Get a block of wood and a hammer and smack the piston tops. This will help get the PBlaster into the ring area. Let it sit for several days repeating the process everyday. It will come loose. You need to bolt a couple main caps back on so you can try to rock the crank back and forth after it's sat a while. It's gonna take some time.
 
Is it standing up or laying on it's side ?
I am sure you have shot the pistons down with liquid wrench or somthing like Blaster.
Do this top and bottom, Do you have a rubber hammer ? look at the stroke and find a piston half way down and put the handle of the rubber hammer on top of the piston and hit the rubber hammer on the head and it will try and drive the piston down, you may want to put three of the main caps back on to do this, I have herd that brake fluid does a good job also,.
 
StrokerScamp said:
Sounds like the rings are rusted to the cylinder walls. There's a product called PBlaster at most any auto parts store. Get several cans and soak the cylinders. Get a block of wood and a hammer and smack the piston tops. This will help get the PBlaster into the ring area. Let it sit for several days repeating the process everyday. It will come loose. You need to bolt a couple main caps back on so you can try to rock the crank back and forth after it's sat a while. It's gonna take some time.
Click to expand...

Well written and said StrokerScamp :glasses7:
 
I was holding my breath waiting for an answer. I thought I was going to hear I am screwed because the block is toast. This motor is slated for a stroke job and I was looking forward to it. The motor is sitting on its end but I have had it on its sides, upside down, you name it. How do I lift it? Grunt and groan. This PB Blaster sounds like the trick. It will be no problem to put the main caps back in. It'll be a week but I'll let you know how it goes. A million thanks guys
 
The way I unseize motors is a bit different than ss method. Leaving the motor intact,I remove the plugs and fill every cylinder with diesel via a turkey baster. Then I fill the intake as well,and the crank case. Then I remove the dist and valve covers and using my priming tool I prime the system,and then try to turn it over by hand. Gently now as using force could break rings. Once I have things moving I turn it over until the cam holes line up with the head lube holes and make sure both heads get plenty of lube.

You can let the diesel sit for a while if it's really stuck.
 
First, I unbolt the rod caps and take the caps off. Then, I beat the snot out of them from the bottom using a peice of steel tubing on the pin bosses. They will break lose and you are not using the pistons again. The problem you may have is the rust pits it will inevitably have made in the bores where the rings were stuck. Remove the ones you can reach first, then one by one the oter ones. Also, never beat DOWN on the pistons... It's a good way to possibly mess up the crank, rod, or cylinder wall. Always hit them UP the bore.
 
try magic marvel mystery oil.that will get the engine to turn over. wait like a day or so after u do it. it should turn.u can get at any autopart stores&walmart.
 
If you aint already, you might want to get a piece of plywood pretty large, to roll the engine onto so you have a nice place to work on the engine while you are beating on it :). My friends used to use used oil, used tranny fluid and desil mixed together in thirds, to unsitck motors, since you could make up a gallon or more of it for practically free. Then put that in an old dish-washing liquid bottle to squirt all down the cylinders and all over the place. That is called "hill-billy mystery automatic engine de-stuckifyer oil". It is patend pending.

.
 
If you do not have an engine hoist, put some mechanical advantage to work for you. If you want to get the block up on a work bench and have no friends handy, you could rig up a hoist by using some chain, a long 4x4, and something sturdy to use as a fulcrum. I had to do this once. Because the work bench height was high, I did it in stages using milk crates as the fulcrum. Lift the block onto a crate, then add another crate to the fulcrum and then another to the one under the block. Once the block is high enough, you could roll it onto the bench from there. Just be careful to keep the crates stable when jacking.

I have since then purchased an engine hoist on sale from Harbor Freight.
 
This may sound crazy,but I broke one loose using iodine. Learned that trick from an old mechanic. Squirted it around the pistons,let it soak a few days,and wala.
 
I had the same problem with a 383 also,but all the piston rings weren`t froze, just the cylinders with intake valves opened. 1st don`t get in a hurry. I rolled it on a piece of plywood to protec the floor.Rolled the block so the cylinders were straight up.Soaked the cylinders w/ brake fluid for a couple days then kerosyne for awhile then w-4o. Kept flipping the block from one side to the other chock it so it stays straight up..Cut a piece of 3/8th plate steel same diameter crank flange,drilled holes to match the flange,welded a 1-3/4 nut to it,( don`t use hamonic balencer bolt to turn the crank) used 3/4 in. breaker bar and 1-3/4 socket w/ a 4ft. cheeter pipe.Just keep working it..Once it starts to move just a little,you got it made! Depending on how bad it is you may want to soak it some more...Don`t use a-lot of force,,you may bend some rods... Use someone to help keep the block from flipping over..
 
I'm not sure what your budget is or what you plan on doing with the engine, but if it was sitting outside and exposed you may want to consider finding a better core to start with. I've gotten involved with rusted motors twice and both times was a disaster. Cast iron loves to rot when exposed and the cylinder walls may be pitted badly enough to not be able to be cleaned up by boring the block. I'll never waste my time and money on a rusted/seized motor again. Its cheaper, better and easyer to start with a core that was under a closed hood with the air cleaner on it.
 
I managed to get the cam out and now two pistons. The cylinders look fine so far. I can move the crank easily but rotating it has been a problem. If I could reach the last 4 nuts on the end of the rods, I could take the crank out and pop the pistons out.

I have a different wrench that might allow me to reach the last four nuts on the rods. Once done, the crank should lift right out and I can knock the remaining pistons out. So far the cylinders look good except for the ding.

On more question. I noticed that there is "ding" at the top, the ridge of a cylinder as if hit with a hammer. It is only the rim and has left a rounded mark where there was a ridge. Is this a fatal flaw for this motor? The rest looks good, not as much rust as I thought.
 
It took some mental engineering but I finally got it done with the motor sitting on the garage floor. I used a bench box wrench to get to two of the four rebellious rod nuts. Although I could reach the last two with that wrench, the space between the crank lobes would not allow me to turn the wrench. I could get a socket on them but could not generate enough torque to turn them and an extension wouldn't fit. What I tried next was a deep socket and used it as both the socket and an extension for the wrench. It worked like a charm. The crank came right out. Six pistons popped right out but the last two put up a fight. The driver's side rear piston was caked in dried sludge but finally surrendered but not the passenger side piston. It was a bear. It was the only one that was dried and had some rust. Here it is what I figure. It was stored in a dirt floored barn, (this guy had about 30 383s and 10 or more 440s), on its face. I figured that by the amount of dirt in the crank pulley. The oil eventually drained out of the cylinders into the pan. But the pan had a hole and the oil drained out of that. Nevertheless, enough oil remained in all but one cylinder and the crank to keep things lubed and from rusting. I don't know if it was cracked or not, but the last piston broke as I punched it out. Most of the top broke off. The block and cylinders all look good. Also, the date on the side is 2/26/68. Does the February 68 date make it a 68 motor?

The reason I posted all of this was in case someone else goes through this with no help. Several of my neighbors suggested I put the motor on an engine stand. I just shook my head. Of course I have an engine stand. But what was I supposed to do, tuck the engine under my arm and bolt it to the stand? I had no help at all and the motor was deilvered on a pallet on my driveway. I had to figure out how to tear it down, plus dealing with all that went wrong, knowing I would have no help. Maybe someone else will be in the same situation.
 
Ever tried turning a engine stand on its side, bolting to an engine then stand it up without a cherry picker ? My son and I did it but it was a 1.9 ltr 4 banger from a Escort.
We turned the rebuilt engine over into a wheel barrel and rolled it outdoors so a wrecker boom could put it into the car.
 
kleen flow diesel fuel conditioner is awsome for stuck engines and anything else stuck just pour it in and wait a day or two and it will free up promise
 
Good idea. I didn't pu it on a stand due to space considerations. But eventually I'll have to put it on something to take it to a shop and to store it when I get it back. Everything is engineering a solution and your's is one of the best I've ever heard. I typically have no help but I think your idea will work. Thanks for the reply.
 
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