Hey everybody, I've run into something that I've not had to contend with before. I'm working on a '58 348 that I just pulled out of my Belair Sport Coupe. According to the inspection sticker the car has been sitting for about 10 years. After pulling the heads off, I've found that the pistons are seized to the cylinder walls. One of the pistons has almost copmpletely deteriated from something in the cylinder while it sat. For the last week I've been spraying down the cylinders with Liquid Wrench, and yesterday shattered a brand new hickory hammer handle. So, with that said, does anyone have any other ideas, or suggestions on what to use to get the pistons out of the cylinders? I can't get the crank out until I get the crank moved, and I can't move the crank until I get the pistons out. It's a vicious circle. Any help would be appreciated. Thanks
I don't know of anything better to use than Gibbs Brand. You can read about it here: http://www.roadsters.com/gibbs/ If you try it, first wipe away as much of any other liquids or dirt. Then spray the Gibbs where it's needed. Since you're working on something that's badly frozen, it's important that you give it enough time to work. I suggest letting it soak in for a minimum of 48 hours. Dave http://www.roadsters.com/
Bite the bullet and destroy the pistons-hole saw the middles out of them and get rid of the rest with a hammer and chisel. You weren't going to save them anyway plus you'll need to bore the block. quote=Belair348;2972698]Hey everybody, I've run into something that I've not had to contend with before. I'm working on a '58 348 that I just pulled out of my Belair Sport Coupe. According to the inspection sticker the car has been sitting for about 10 years. After pulling the heads off, I've found that the pistons are seized to the cylinder walls. One of the pistons has almost copmpletely deteriated from something in the cylinder while it sat. For the last week I've been spraying down the cylinders with Liquid Wrench, and yesterday shattered a brand new hickory hammer handle. So, with that said, does anyone have any other ideas, or suggestions on what to use to get the pistons out of the cylinders? I can't get the crank out until I get the crank moved, and I can't move the crank until I get the pistons out. It's a vicious circle. Any help would be appreciated. Thanks[/quote]
This guy maimed the piston tops to get them out. not so good if you want to run those pistons, but if they are going to be replaced anyways and you get desperate... http://www.flatheaddrag.com/gpf/gpf7piston.html
I had this happen to one I got as well,I bet the cylinder walls will not look so well after you do get the pistons out,so you can beat on them to get them free. you will need new ones anyway. I used w-d 40,and let it sit for a few days,I just started smaking the top of the piston. good luck
Thanks guys. I think next week I am going to bite the bullet and start with a brill bit and a good cold chisel. My brother dissolved an aluminum piston trying to clean it with ammonia one time, I was hoping someone knew of something that would attack the aluminum without hurting the block. Thanks and I'll try to post some pics if I actually do get them out.
Seriously - Coca Cola works. The phosphoric acid in it will eat the rust. The beauty of it is that although it also LOVES to eat aluminum, there just isn't enough in the stuff to do much to the pistons, and it ends up attacking the rust on the rings instead! Dump it in, wait overnight! ~Jason
combustion chamber cleaner, the kind you spray into the carb when the engine is running, well that stuff is great as a penatrating fluid.
plus and some pb blaster got the pistons out of my caddy engine. took some patience but just work that round bit in a circle around the outside of the piston and it will come out or break into pieces.
Put some Marvel Mystery Oil in bores. Let sit for a couple of days. Stick a BF breaker bar on end of crank shaft. Do not use this as an excuse to prove your manhood by pulling on that bar like a mule. Just put enough pressure to sort of rock it. Reapply MM Oil and repeat. Might take as long as a week, but if it's able to break loose, this will do it. Beating on and cutting shit up shouldn't commence until the good old, worked since Hector was a pup,(and he's an old dog) non destructive methods have been tried.
I don't think pounding on frozen pistons is the best idea,it amazing how easy a rod can get tweaked from the beating on the piston.I rig a tool like a puller across the bore and screw it down onto the piston head.Yeah,the 348 has an odd angle but the piston only needs to move a thousands or two to break free.Use your brand of penatrating oil too.If the pistons are corroded like you mentioned the piston head may giveway. Lye will destroy aluminuim in a day or two and simply clean the rust and grease off steel.Lye is caustic stuff,googles,face shield and rubber gloves.
Brake fluid is the miracle drug for this. Pour on top of pistons and let it soak for a couple of days. I have unstuck old Jeep flatheads that had been sitting out for 25-30 years. Yes, i thought it was crazy too, until I tried it. Thanks, Lyman.
well since common sense doesn't seem to be around today, i'll be more specific...remove the crank before commencing on the piston beating
we always used p.b. blaster and diesel fuel some times we would just add a little every day for a month or so and try to use a breaker bar to rock it back and forth
I know a guy who is into old stationary engines. When he gets a stuck one (most of em) he puts a grease nipple in the plug hole and just pumps the piston out. I know your 348 has to come out the top, but once it starts moving it'll only get easier.
Thanks for all the suggestions guys, that's why I came here when I figured out I had this problem. The block has Pepsi sitting in 4 of the cylinders right now, I put it in last night so I'll check it out later today. Thanks again.
It may vary by engine but in every case I know of, you can't remove the crank if you can't rotate it. The big ends of the rods won't get out of the way.
Both great ideas. Stationary engines are my side hobby and there are engines I have seen in person that were UGLY. I'm talking standing water in the cylinders for 50 years. One that I have seen required 8 tons of force to unstick, even after heating the cylinder to expand it. What I would recommend is drenching the top of the pistons with Kroil or PB Blaster (both excellent penetrants). Let them sit for about a week, gently tapping with a ball-peen hammer. Tapping the piston is a huge help. After a week is up, cut down a 4x4 to the size of your bore. Dish the center so that it only contacts the outer edge of the piston. You can and will punch holes in the piston if you hit the center. Then, pound on it with a good sized sledgehammer and it will come loose. If that fails, make up a plate from 1/2" steel and pack the cylinder with grease. DO NOT let any air pockets remain because they will make a huge mess when the piston does come loose. The nice thing about this method is that the pressure causes the cylinder to expand slightly, loosening its hold on the piston. Go slowly because grease guns can and do make over 5,000 PSI. If that fails, you're really fucked, but not totally down and out. You can also try baking the block to loosen the bond. Bring the whole thing up to about 800-1000 degrees Fahrenheit and let it sit for about 20 minutes. Pack it in lime and let it cool slowly. Cracking the block by cooling it off too fast is bad. After waiting a few days for it to cool off, oil and pound again. If all that fails, destroy the piston.
Enough soaking already!!!! If you don't plan on reusing the pistons just get a BFH and a long peice of 3/4 rod and beat the things out. Start with the ones at the top of there bores. You can usually get the crank out by taking about three pistons, and a few rod bolts out of the way. Just hammer on the pin boss of the piston and be carfull not to let it slip off into the bore. It's the only way to fly. Jeff
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