cylinder removal

NoiseyNorton · Sep 2, 2015

I am in the process of removing my cylinder from my case and it would appear that my pistons are seized to the walls. (motor was sitting outside for some time prior to purchase)
It has been soaking in just about everything i can think of for about a week with no help. What are some ideas on removing this darn thing.
How much heat is too much? I have used a little propane torch long enough to realize its not gonna work (10 minutes)
I have an induction heater that can get my barrel glowing red with pistons only minimal heating but what is too much? i would rather not be calling steve maney for his alum afterwards...

I am not opposed to throwing it off the local bridge to hopefully split them apart, but would like more conventional ideas

Thanks
Nathan

Interbak · Sep 2, 2015

This might be the radical approach, but it worked for me. The engine in one of my P11 projects had been seized solid for a very long time. I soaked in every imaginable rust eater I could think of, tried every home grown remedy and after 6 years, it still would not budge. A guy in the club, local diesel mechanic, said he had good luck with dry ice. I managed to get the jugs up far enough to split the cases and take the bottom end apart so I could send him only the barrels with pistons and rods still attached. He took rubbing alcohol and chilled it down with dry ice to whatever temperature that is, super cold! He poured the alcohol into the cylinder, one at a time, and after it stopped bubbling he dumped the alcohol, and was able to hammer the pistons out with a wooden block and mallet. Obviously you need to use extreme caution and wear proper protective gear when dealing with this stuff, the frost bite could be severe.

It worked, B

Nater_Potater · Sep 2, 2015

NoiseyNorton said:
I am in the process of removing my cylinder from my case and it would appear that my pistons are seized to the walls. (motor was sitting outside for some time prior to purchase). I have an induction heater that can get my barrel glowing red with pistons only minimal heating but what is too much?

You're fighting aluminum pistons in iron sleeves and/or barrels. As I'm sure you know, any heating will only swell the pistons tighter. That being said, there is something in thermal cycling to help break the bonds.

Here's how I would advance on the front:

How about cola? No fooling. R/C is the best, as it has the highest concentration of the magic ingredient (phosphoric acid). Let it sit on the piston crowns for a few days. If no joy:

I have broken pistons loose (in tractors) by pouring about an inch of ATF into the cylinder, heating the whole mess just short of flash point (well, maybe not quite that hot...), then tossing some chunks of dry ice into the ATF pool. This helps to pull the aluminum piston away from the bore, allowing the ATF to shimmy into the gap.

If they still won't come loose, you may have to resort to making a heavy strap that bolts across the bore in place of the head, then thread through the center for a large bolt to drive against the piston crown. Not pretty, but I assume you'll be replacing the pistons anyway.

NoiseyNorton said:
...but would like more conventional ideas
Thanks
Nathan

Maybe not conventional, but has proven to be effecting in the past.

Good Luck,
Nathan

texasSlick · Sep 2, 2015

You would have to put the head back on. Then fashion a dummy spark plug (break off insulator) and drill and tap it for a grease zert. Pump grease into the cylinder(s) with a hand grease gun. You can develop a lot of pressure, 150 psi or so, and when applied over one piston, will develop nearly 1000 lbs force. If you get 100 psi pressure, that will apply nearly 650 lbs force.

Good luck.

Slick

NoiseyNorton · Sep 2, 2015

Thanks for the ideas, not sure exactly sure on your grease thought. are you say pump full of grease and then apply air pressure to the cylinder? or just pumping grease will make that kind of pressure?

I have a company I deal with that has dry ice so i will have to give that a go.

Lets keep hearing some ideas?

Thanks
Nathan

BritTwit · Sep 2, 2015

I like the Cola approach; it has worked for me on corroded parts too.
For really heavy corrosion problems I use Metal Rescue Rust Remover
It chemically dissolves the rust/oxide/patina only. Will not harm other metal parts.
If the slugs are down aways in the bore, just fill the cylinder until piston is below the level of fluid. Let sit for a day or 2.

Then use the block of wood, and rubber mallet tapping.

NoiseyNorton · Sep 2, 2015

BritTwit said:
I like the Cola approach; it has worked for me on corroded parts too.

If the slugs are down aways in the bore, just fill the cylinder until piston is below the level of fluid. Let sit for a day or 2.

Then use the block of wood, and rubber mallet tapping.

I will have to try the cola; currently is it sitting with a mix of ATF, acetone, powerlube, PB blaster, windex (was getting desperate), couple squirts of motor oil and i spit in the one after 20 minutes of beating on the pistons and needing a shower from the oil splashing all over my garage. Its been about a week and then i started adding random stuff. Could blow up from the chemical mixing for all i know. I will clean out the old fluids and try straight cola.

The pistons are down about half way so it was nice being able to have some down stroke if they will move and be able to soak this concoction in.

again

Thanks
Nathan

texasSlick · Sep 2, 2015

+1 on the Metal Rescue. Let it soak for a day or two.

If that fails, try the grease ... yes, you can develop 100 - 150 psi pressure with a hand pump (maybe more). In theory, 100 psi air pressure will develop as much force as 100 psi grease, however, the air is more likely to pass thru ring gaps. Since you report you have liquids standing over the pistons, there may be no gaps, so air is worth a try.

Let us know what happens.

Slick

guest76 · Sep 2, 2015

Do you have a compressor and airline?

Fill the cylinder with engine oil, put the head back on and attach the airline to the spark plug hole.

Leave them pressurised for a couple of days - you're not looking to force the pistons down, just force the oil between the pistons and barrel.

dennisgb · Sep 2, 2015

I've posted this before and it works a trick.

If you have the head off then this will work.

I tried everything I could think of on this frozen Triumph engine then I found this on the web. Angle iron and a carriage bolt. Turned very easy and freed the engine instantly.

BritTwit · Sep 2, 2015

Oh yeah.
The nuclear option! :lol:

That will definitely work.

Nater_Potater · Sep 2, 2015

dennisgb said:

Thanks for the photo, Dennis! That's exactly what I was trying to portray in my #3 option. Nathan, keep in mind that most of these options, including the bolt, take place over time. With a puddle of ATF on top of the piston, crank down the bolt until you're uncomfortable with the force exerted, then come back in the morning and repeat.

NoiseyNorton said:
...windex...

Maybe if you're Greek... :wink:

o0norton0o · Sep 2, 2015

Don't you worry that if both pistons are stuck and you loosen the single piston with the angle iron method, that you are now driving that force onto the connecting rod, across the crankshaft bearings and onto the other connecting rod to pull on the other stuck piston??? I would worry that I would damage the crank..

I would pull the barrels upward enough to clear the bottom end, then split the case and unbolt the connecting rods. Then I would use a hydralic press and penetrating oil to loosen one piston at a time... no windex...

dave M · Sep 2, 2015

I had to resort to drilling holes in the top of one piston in my G15. Ths gave me enough room to fit a hacksaw blade down one side and saw a slot until the piston loosened up. The piston and bore were trash anyway so not much danger of damaging anything. I did split the cases and remove the crank first, also applied lots of heat.

dennisgb · Sep 2, 2015

o0norton0o said:
Don't you worry that if both pistons are stuck and you loosen the single piston with the angle iron method, that you are now driving that force onto the connecting rod, across the crankshaft bearings and onto the other connecting rod to pull on the other stuck piston??? I would worry that I would damage the crank.

On the Triumph it took almost no force at all with this method. I just started turning the nut and it freed up. I had been soaking it for a couple of days. Could not move it with a rubber mallet, piece of wood and a hammer or turning the crankshaft nut (was advised not to do that because you can break it).

If you start turning the nut and it doesn't move, then I would be concerned that you might break something...but then again maybe not. The force is being applied to the crank to rotate...if stuck at the bottom of the stroke it might not work...but anywhere else in the rotation it should work IMO.

Northton · Sep 2, 2015

I was at about the point you are now. Soaking, heating wacking as in the above pic. What finally worked for me was heating the INSIDE of the cylinder walls above the pistons with a torch and then using a cold chisel, tapping down on the edges of the pistons right beside the cyl. wall, alternating back and forth between the L and R and working around in a clockwise direction. Took a while but if it was easy,... this would be called Access Honda....

texasSlick · Sep 2, 2015

gtiller said:
Do you have a compressor and airline?

Fill the cylinder with engine oil, put the head back on and attach the airline to the spark plug hole.

Leave them pressurised for a couple of days - you're not looking to force the pistons down, just force the oil between the pistons and barrel.

I like gtiller's approach, but I would substitute Metal Rescue (phosphoric acid) for oil. The seizure is due to the iron rings rust welded to the iron cyl walls. The phosphoric acid will dissolve that rust.

Then wood blocks with a 12 lb hammer may be all you need.

oOnortonOo has a good concern, but I do not think raps with a hammer are any more stressful on the crank than pre-ignition pings (not desirable, but not immediate destruction). My grease method, or dennisgb's screw method applies a lot of pressure, but this is not a shock and nothing compared to the pressure in the cylinder at WOT.

Finally, Nater-Potater's suggestion to put on the pressure and leave it is good.

Good luck with it.

Slick

NoiseyNorton · Sep 2, 2015

I will try these suggestions and get back. If I end up destroying the crank all the more reason to upgrade. I can justify to the ball and chain that way? But hopefully I don't have to go that route.

Also I would love to be able to spilt the case but as the cylinder hasn't even budged not sure if that route will work. Maybe I'm still able to?

Will attempt the pressure over night and see if that works. I have had great success with ATF soaking. So hopefully a few more days will do the trick. If not I will go more abusive routes.

The Windex was more of a just frustrated so I dumped it in. Knew it wouldn't work.

Thanks
Nathan

worntorn · Sep 2, 2015

Re the grease option mentioned by TexasSlick- this is how a hydraulic track adjuster works on large and small track machines. A regular grease gun easily lifts and moves tons of track to set the correct tension.
I believe the pressure is much higher than 150 PSI at the fitting though. Think of the length of the lever, the pivot position and then the tiny orifice in grease fitting. Then multiply that pressure per sq. Inch by the area of the stuck pistons. It's likely several tons of pressure can be applied in this way.

Glen

moond850 · Sep 2, 2015

I have had this problem several times and it seems a through soaking with WD , then into the vice or suitable motor mount and with a 6'' long piece of a 4x4 wood post. (It's actually 3 1/2 x 3 1/2.) I'll trim it to size across the diagonal and its ready. Insert the post, take a rubber hammer and whack the top of that post until the piston moves. If it doesn't, I go for an old framing hammer. That has usually worked. I tried the slow pressure increase method, but it seemed that initial shock with a hammer breaks the piston rings slightly off the wall, and then a few good smacks with the hammer should release the piston.
Sometimes it doesn't work out that way. : )

cylinder removal

NoiseyNorton

Interbak

Nater_Potater

texasSlick

NoiseyNorton

BritTwit

NoiseyNorton

texasSlick

guest76

Guest

dennisgb

BritTwit

Nater_Potater

o0norton0o

dave M

dennisgb

Northton

texasSlick

NoiseyNorton

worntorn

moond850

Similar threads