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914World.com _ 914World Garage _ How do I remove stubborn pistons / cylinders?
Posted by: rwilner May 18 2012, 05:18 AM
So with some less-than-gentle persuasion with a rubber mallet, I got the heads off my 1.7 core.
This engine didn't turn over and it's obvious why...the cylinders have rust on the inside and the pistons will not budge. I need to get the Ps and Cs off and I don't care if I damage them as they're toast anyway, but I need to keep the case pristine as this is what I'll be using for my rebuild (really it's why I bought the core).
So, any tricks to free up and remove the pistons and cylinders? More persuasion with a rubber mallet? Gallons of PB blaster? Mild explosive?
Posted by: ArtechnikA May 18 2012, 05:59 AM
Penetrants, heat, patience.
If CHT is in the 350º-400º F range, the cylinders are in that ball park too, so they can take a bunch of heat. This will expand the bore and make more room for the penetrants to get where they need to go to do what they do.
KROIL also has an excellent reputation and I use it and PB Blaster (and others...) I don't think I've ever seen KROIL at a FLAPS but any decent gun store will have it. (Although this might be elusive in Boston, as well.) There are always the online sources...
Posted by: hot_shoe914 May 18 2012, 06:32 AM
Rubber mallet. 
Posted by: RobW May 18 2012, 07:46 AM
Wire brush and pick at the base too. Penetrating oil. I didn't have any trouble pulling my stock 2.0 down...
Posted by: Rex-n-effect May 18 2012, 07:56 AM
Mine had the same issue when i got it. They had been soaked in water for about 12 years so you can imagine what kind of bonding had been going on. They were so bad that, well lets just leave it at that. I soaked in rust penetrant for weeks before i tackled this. When this had no effect i ended up using the BFH (metal) to knock them off. I had pieces of cylinder fins all over the shop but i got them off. When i got too close to the case i used wood blocks and brass drifts to wack the crap out of it. Took a long time but they eventually came off. Good luck!!!!
Posted by: RobW May 18 2012, 08:10 AM
Mine had the same issue when i got it. They had been soaked in water for about 12 years so you can imagine what kind of bonding had been going on. They were so bad that, well lets just leave it at that. I soaked in rust penetrant for weeks before i tackled this. When this had no effect i ended up using the BFH (metal) to knock them off. I had pieces of cylinder fins all over the shop but i got them off. When i got too close to the case i used wood blocks and brass drifts to wack the crap out of it. Took a long time but they eventually came off. Good luck!!!!
Yikes!
Posted by: rwilner May 18 2012, 08:37 AM
holy crap.
Looks like I have my work cut out for me.
Posted by: Cupomeat May 18 2012, 08:54 AM
It usually isn't that bad, but be careful with the cyl to case seating.
Once you start to get somethings moving, you'll be pushing some stuck piston/cyl sets off the block as you drive other ones in and apart. Take your time, hit hard but squarely and as you won't be saving the Ps and Cs, use a BFH.
Preserve the case!
Posted by: injunmort May 18 2012, 08:57 AM
turn one side up, fill cylinder with atf and acetone, heat the cylinder with a torch. tap piston with rubber mallet and they should free up. if the piston is down in the bore, use a piece of wood as a drift to get it free. repeat on other side. good luck, with some paitience and heat they should all come free without much drama.
Posted by: rwilner May 18 2012, 10:32 AM
turn one side up, fill cylinder with atf and acetone, heat the cylinder with a torch. tap piston with rubber mallet and they should free up. if the piston is down in the bore, use a piece of wood as a drift to get it free. repeat on other side. good luck, with some paitience and heat they should all come free without much drama.
By doing all the banging with a hammer, is there any risk of transferring the loads to the engine case internals and damaging it...for example, damaging the crank bores?
I am planning an align bore anyway...
Posted by: injunmort May 18 2012, 01:11 PM
i dont think i said bang on it with the hammer, i believe that the term i used was tap on it with a rubber mallet. the heat expands the cylinder, the acetone and atf attack the rust and the tapping frees the rings from walls of the cylinders. so simple a cave man can do it.fwiw.
Posted by: rwilner May 18 2012, 01:21 PM
i dont think i said bang on it with the hammer, i believe that the term i used was tap on it with a rubber mallet. the heat expands the cylinder, the acetone and atf attack the rust and the tapping frees the rings from walls of the cylinders. so simple a cave man can do it.fwiw.
right! I quoted the wrong individual, others were saying to bang hard with BFH's.
I will try this method first.
Posted by: Qarl May 18 2012, 01:25 PM
Great video here...
http://www.ephotomotion.com/914engine/index.htm
Posted by: r_towle May 18 2012, 09:26 PM
Bring it over here on Saturday.
We have the tools and anger...
Or
Go to autozone and get three gallons of pb blaster and a plastic tub.
Soak for a week or two.
Rich
Posted by: rwilner May 19 2012, 07:35 AM
Bring it over here on Saturday.
We have the tools and anger...
Or
Go to autozone and get three gallons of pb blaster and a plastic tub.
Soak for a week or two.
Rich
Rich
You around next weekend? In laws are staying with me this weekend.
Posted by: tomeric914 May 19 2012, 09:51 PM
Sledgehammer and a 2x4. Look at my build thread to see what I was up against.
Posted by: Cupomeat May 19 2012, 10:28 PM
Confucious says, Yes, even the worst looking situation
will yield to a good hammer...
I thought this one would be difficult, but it was pretty easy!
Good luck!
Posted by: euro911 May 20 2012, 01:20 AM
Just be really careful when heating up any chemical compositions ... when the liquids form into vapors, you don't want to inhale them 
Wear a quality mask with chemical-rated filters.
Posted by: rwilner May 20 2012, 07:15 PM
Ok well, I did a lot of beating with a hammer, heating, and soaking with pb. The cyls are all loose from the block but the positions are still bonded to the cylinders. I broke most of the fins off one of the cylinders trying to separate it from the piston using an oak dowel as a drift.
My torch is a standard brazing/plumbing soldering torch, maybe it's not putting out enough heat.
What's the best approach -- try to bear the cyl off the piston or try to beat the piston down into the cyl?
Posted by: moparrob May 21 2012, 09:24 AM
Just curious- would a cutting torch work?
Posted by: ArtechnikA May 21 2012, 09:31 AM
Just curious- would a cutting torch work?
Hmmm - molten aluminum, burning steel, excess of oxygen.
Check out 'Thermite reaction' and then decide if this is a good idea ;-)
I think I'd sooner try to split the cylinders with a rotary cutoff disk...
Posted by: rwilner May 21 2012, 10:03 AM
I think I'd sooner try to split the cylinders with a rotary cutoff disk...
Not sure this would net me a lot because they'd still be rust-bonded to the pistons. Plus, it would be pretty tough to cut through the underside of the cylinder without damaging the case.
I think i'll keep trying to beat the piston into the cylinder after another PB / ATF / acetone soaking.
Good thing I am not in a rush.
Posted by: Rex-n-effect May 21 2012, 10:15 AM
I feel your pain! Cupomeat's picture looks like factory fresh compared to what i was working with. Patience, persistence in the proper position and good arm strength will net you the results you need. Good luck!!!!!
Posted by: ArtechnikA May 21 2012, 10:30 AM
I think I'd sooner try to split the cylinders with a rotary cutoff disk...
Not sure this would net me a lot because they'd still be rust-bonded to the pistons. Plus, it would be pretty tough to cut through the underside of the cylinder without damaging the case.
Yes, but ...
Technically, they're rust-bonded to the piston rings. With a big slot down the side, you will have broken any residual ring tension you might have had. But the big plus is that right now, your penetrants can't get to the #2 or oil ring because they have to get through the top ring first. So you're providing a lovely path to get penetrants directly to all the rings.
And yes, you can only get 'near' the base of the cylinder, but that may be enough. Best-case is all your pistons are at mid-stroke. Worst-case is two are at TDC and two are at BDC - that will really limit your access to those.
Posted by: LotusJoe May 21 2012, 10:54 AM
So with some less-than-gentle persuasion with a rubber mallet, I got the heads off my 1.7 core.
This engine didn't turn over and it's obvious why...the cylinders have rust on the inside and the pistons will not budge. I need to get the Ps and Cs off and I don't care if I damage them as they're toast anyway, but I need to keep the case pristine as this is what I'll be using for my rebuild (really it's why I bought the core).
So, any tricks to free up and remove the pistons and cylinders? More persuasion with a rubber mallet? Gallons of PB blaster? Mild explosive?
A can of Coca Cola poured into each cylinder...let soak over night. Real Coke not Diet or Generic. I've freed up a lot of engines over the years.
Posted by: jcambo7 May 21 2012, 11:18 AM
So with some less-than-gentle persuasion with a rubber mallet, I got the heads off my 1.7 core.
This engine didn't turn over and it's obvious why...the cylinders have rust on the inside and the pistons will not budge. I need to get the Ps and Cs off and I don't care if I damage them as they're toast anyway, but I need to keep the case pristine as this is what I'll be using for my rebuild (really it's why I bought the core).
So, any tricks to free up and remove the pistons and cylinders? More persuasion with a rubber mallet? Gallons of PB blaster? Mild explosive?
A can of Coca Cola poured into each cylinder...let soak over night. Real Coke not Diet or Generic. I've freed up a lot of engines over the years.
It's amazing we even drink that stuff too...
I use it(coca cola) to clean of my uniforms and rags when they get too greasy and oily. It works great.
Posted by: ArtechnikA May 21 2012, 11:26 AM
It's amazing we even drink that stuff too...
I use it(coca cola) to clean of my uniforms and rags when they get too greasy and oily. It works great.The tree-huggers made the detergent manufacturers pull phosphorus out of their products - but it's not the only source. I guess it's OK for the environment if it's been processed by a person first.
Which kinda begs the question - if it's phosphoric and carbonic acid you're after, why not just use Ospho and get it in higher concentration ?
Posted by: r_towle May 21 2012, 08:05 PM
You are already trashing the pistons, get a hole saw and take out the top.....
Or, turn it on its side and fill each cylinder with coke....keep doing that till it will breake free.
Remember.....you really only need one side to come off....then you can unbolt the case and remove the rod bolts for the oTher side
Posted by: rwilner May 23 2012, 06:26 PM
the coke trick worked! 
Well, coke, plus whacking the living s$!t out of it with a piece of 2x4 and oak dowels, then using a big steel drift.
ONWARD!
Posted by: rwilner May 23 2012, 06:26 PM
the coke trick worked!
Well, coke, plus whacking the living s$!t out of it with a piece of 2x4 and oak dowels, then using a big steel drift.
ONWARD!
Posted by: euro911 May 23 2012, 07:08 PM
Congrats.
I guess the old saying, "things go better with coke", is true 
I'll have to try that on a couple of seized-up IDFs 
Posted by: rwilner May 24 2012, 06:05 AM
If this failed, my next step was to ask my phd chemist buddy to mix me up some 2M phosphoric acid, which is the "active ingredient" in coke that makes it do its thing.
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