Need help unsticking a siezed / stuck Hornet Engine

nhp1127 wrote:

I'm looking at purchasing a 52 Hornet Coupe with a stuck engine. From what I know, the car has sat indoors for about 9 years and apparently had a blown head gasket when parked. Water went into the cylinders and the piston rings have rusted to the cylinder bore. Don't know if there is more damage to it. Besides tranny fluid or diesel fuel, what products have worked to unsieze an engine?

Assuming you've seen the cylinder bores and know they are rusty, it will require a professional shop to unstick it. My block was stuck and there was no water damage. No matter what I tried I could not release the pistons. You can assume the valves and valve guides are also stuck. I was able to get these out myself but it took weeks of soaking, then heat, then pounding. The valves and guides either came out together or separately, usually broken or shattered however.

my forumula for "jungle juice" is a 50-50 combination of WD40 & Marvel Mystery Oil.

To get the pistons out I'd recommend dropping the pan & dropping the end caps off the pistons so that IF you're able to free up the pistons/rings with "jungle juice", you can pound them out.

Getting the valves out another story, so to speak, but getting the pistons out easily, altho may be time consuming for the "jungle juice" to soak by the rings, may, hopefully, prevent scoring the cylinders.

ROTSA RUCK!

Lots of discussion on this on the tractor board I frequent. Some lab did a test, and best results for penetrating was 50/50 mix of ATF and acetone (Mix it up as needed, because it takes a pretty good container to keep acetone from evaporating). I think Kroil was second, can't remember the rest. Many on that board swear by ATF, mixed with various things.

Pull the head, clean out all the debris from the cylinders. Pull the pan and loosen all the rod caps slightly, just enough to allow a small amout of movement of the piston should you get lucky.



Sand or steel wool all the rust from the cylinder bores that you can reach, clean tops of pistons and use air gun to blow all the crud out you can from around the pistons and bore.



I have had sucess with white vinegar poured into bore and left for a few days to clean out the top layer of rust and oxidation. wash out with water and blow dry with air gun.



Do not leave solution in for an extended period of time as it will eventually eat up piston.



Use your choice of penetrant/lubrication and go on vacation for a few days/weeks.



Obtain a 1/2 in. circular slug of steel approx 1/8 smaller than bore, place on top of piston and use an air hammer or panel cutter with a blunt end to hammer the slug over its entire area, especially around the outside edges.



If the bores are in good shape you can use plastic or leather as a filler between the circular slug and the cylinder bore to prevent any unintended damage to the cylinder wall.



The light/quick impacts from the hammer seem to make the penetrant go in quicker and loosen up the piston and rings. The circular metal slug spreads the impacts over the top of the piston and dosent break the edges of the piston down like other methods I have tried.



Be patient and allow time for the penetrant to seep deeper between the pistons and cyl. walls. Add more penetrant as needed.



Use 3/4 drive ratchet and cheater pipe + large friend on crank bolt to put pressure on pistons to get movement. Turn both clock wise and counter clock wise.



Oil up valve stems and try to turn valves which are off seats, use air hammer directly on center of valve to assist penetrant getting into guide area.



Dont use air hammer at too high settng or too hard on valve which might deform head of valve.



You should see some movement on the parts involved after a few days.



Start with the pistons which are at an angle with the crank throw, not the ones where the piston is at top dead center or at the bottom of the stroke.



Some where in this process a bigger hammer might be appropriate.



If the engine bores are badly pitted or streaked you are looking at new pistons and bore job no matter what you do.



Relieve the fustration by applying air chisel to pistons and cut them into pieces and remove.



WH

FYI

You received some excellent advice on soaking and patience to free up the motor.The last Hornet motor I dissembled few valves were stuck in the guides and no pistons stuck. (The motor before was just the opposite).I sprayed PB Blaster into the guides to soak then after a few days used a pipe wrench on valve to twist free then rotate upward and out. It seems vibration helps free from hammer blow or Impact Wrench