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Discussion Starter · #1 ·
Got the engine pulled on my 66 and it's a mess, lots of rust. I put tranny fluid on top of the pistons to help unfreeze them.


 

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Look like it may be a good thing the winters are long up there!

I'll be interested to see how that comes out.
 

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Discussion Starter · #3 ·
J-T said:
Look like it may be a good thing the winters are long up there!

I'll be interested to see how that comes out.

So will I ! I've got a least 4 months to work on it.
 

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WOW. thats pretty stuck! My buddy Jordan once tried to PRESS some corroded pistons out of the bores with a 2-ton(i think) press. He succeed in blowing out the cylinder walls. I have had luck freeing rusted pistons with a de-ruster product... name escapes me but I think I have some in the shop... that ATE away all the corrosion leaving pitted but clean metal behind. It was like 4-5 days of applications. Will check and get back to you, danWI
 

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Discussion Starter · #5 ·
I'm going to try and lift the cylinder block off today-wish me luck ! I'm keen to see the condition of the cylinder bore and pistons.
 

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I have seen worse. I have also screwed up ones in better condition than yours by getting in a hurry. Be patient. That is REALLY easy for me to say but not to do.
Don
 

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Sensei
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Patience IS the key...You may not be able to remove the cyls for a couple weeks.... Soak and try, but don't force...soak again..... I've also seen and restored worse.......
 

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Kroil seems to work pretty well, sells a little like snake oil, and smells like a mix of diesel and something? but i've had pretty good luck with it. busted loose a 250 elsinore, not quite as crusty, but I was able to run it, freed up the rings as well, even ran pretty well. Once the oil has had plenty of time to work a few taps on the pistons with a plastic deadblow tends to help with the stiction with out causing undue trauma.
whatever you do, Steve is correct, patience is key!
 

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I'll say it again. PB Blaster is the only thing I'll use in situations like this. It unlocked a Yamaha CT3 for me that looked worse than that. It'd been sitting outside full of water for probably 15 years, with NO HEAD ON IT. Squirted the jug full and smacked with a 2x4 and the jug came off. Then I squirted a liberal amount in the crankcase, and the crank was free within a day if I remember correctly..


GB :mrgreen:
 

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Bird76Mojo said:
I'll say it again. PB Blaster is the only thing I'll use in situations like this. It unlocked a Yamaha CT3 for me that looked worse than that. It'd been sitting outside full of water for probably 15 years, with NO HEAD ON IT. Squirted the jug full and smacked with a 2x4 and the jug came off. Then I squirted a liberal amount in the crankcase, and the crank was free within a day if I remember correctly..


GB :mrgreen:
I'll second PB Blaster, really good stuff. I've never freed an engine with it, but I've used it on rusted bolts and stuff on my car (Newfoundland is the world capital for rust :x ). Sprayed it on and left it a day or two and it worked great. Anytime I know I'm going to work on a part of the car, I'll spray it a day or two in advance, saves a bit of swearing :D

I've also used Rust Check as well with good success.
 

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Discussion Starter · #11 ·
I attempted to get it off today but no luck. I used a soft piece of wood and a hammer to tap around the block. Also used another smaller piece of wood to gently tap each piston ( I tapped the side of the piston above the wrist pin) Nothing moved so I sprayed PB Blaster again and I'll let it sit for a day or two and try again!
 

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rubber hammer.....better use one.... :!:
 

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The next time you go to tap on the pistons you might try to apply some heat as well.. A heat gun and/or an air hammer could end up being your friends if used cautiously...


GB :mrgreen:
 

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I don't know if it would help in this situation but I freed up some stuck bolts and misc items as well as knocked off rust with the old tub of water, steel rod, baking soda and battery charger trick. It pulls off all rust and looks pretty coold also.
 

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Discussion Starter · #15 ·
I've tried the heat gun along the fins to warm up the block and also used a can of computer air on the pistons but no luck yet. I was hoping the can of compressed air (very cold) on the piston would shrink it and the heat on the block would free things up.

I'm thinking of lifting the engine off the floor about a 1/2" , with a strap down the cyl block let the weight of the bottom end separate the two pieces???
 

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REMEMBER, one piston RISES as the other falls.............Keep soaking...
 

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Acid will dissolve the rust. Phosphoric acid is commonly used - glacial acetic will work, probably as well. They may not do the aluminum pistons much good, but I'm guessing they're already not in prime shape. I think I've heard that acid will make a brownish stain on the side covers, but they're probably off, anyway. One of the most effective penetrating solutions is a mix of half ATF and half acetone. In lab tests, it outperformed the commercial products. Of those, KROIL tested as best. I worked at a Benz dealership ages ago - we used an ærosol product that actually got hot when it was sprayed on a rusted part. I wish I could remember what that was - it was quite effective.
 

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Discussion Starter · #19 ·
KERRY said:
Acid will dissolve the rust. Phosphoric acid is commonly used - glacial acetic will work, probably as well. They may not do the aluminum pistons much good, but I'm guessing they're already not in prime shape. I think I've heard that acid will make a brownish stain on the side covers, but they're probably off, anyway. One of the most effective penetrating solutions is a mix of half ATF and half acetone. In lab tests, it outperformed the commercial products. Of those, KROIL tested as best. I worked at a Benz dealership ages ago - we used an ærosol product that actually got hot when it was sprayed on a rusted part. I wish I could remember what that was - it was quite effective.

I like the idea of half ATF and half acetone, it's readily available compared to Phosphoric acid. I might try that mix tomorrow.
 

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gaillarry said:
I like the idea of half ATF and half acetone, it's readily available compared to Phosphoric acid. I might try that mix tomorrow.

Phosphoric acid is common, cheap, and readily available at Farm & Fleet, Tractor Supply Store, places like that - it's marketed as "Milk Stone Remover".
It's my personal rust-buster of choice, I keep a big cooler of it around the shop, and process nearly everything through it.
Mix it down by half with water - it will work for sure.
 
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