Refresh me on techniques to get a stuck piston out of a Cyl.

[Spimothy Leary]

In the past when I had really stubborn rings stuck in a cyl I usually just put the engine back together maybe with a bad head and cored it out to SBT but with recent reductions in core prices it really no longer is a viable option.

I banged apart 2 engines (out of 5 that I had) but 3 of them we're pretty stubborn and I set them aside last month until I got bored... and crap,i'll be dammed, i'm getting bored.

So here I am with 3 engines (seadoo/kawi/yamaha) shoved on the back of the bench, i've already removed the good heads and clean cyl's off and sold them for more than I would have received as cores, and now i'm left with figuring out how to tackle the stuck pistons. Bottom ends are still together at this point. Cyl's won't budge off the cases, pistons frozen solid. Until i'm 100% sure the cranks are toast I'm trying not to damage them.

Its either fight with these engines or paint the house... and I hate painting just slightly more than fighting engines so I want to tackle these over the weekend if I can't find something better to do, like walking barefoot on sharp rocks.

Can anybody share their experience/short cuts ?

What penetrating oil have you had good success with ?

I grabbed a can of Kroil this morning, thought about starting with some of that...which will buy me some time since usually its a set & soak kind of process.

 

[MPower]

My resto 95 800 had been sitting outside for 6 years or so and the pistons were froze solid. Let it soak in WD40 and it popped loose. Then pulled the cylinders and basically pressure washed the crank/case with kerosene.

 

[fitty650sx]

Hammer handle and a dead blow hammer. Never had one that wouldn't give in to a sweet lovemaking.

 

[LouDoo]

You're probably gonna get a bunch of favorite techniques personally I have had good results from Marvel Mystery Oil also ATF, let soak overnight.

Lou

 

[Kwik_uk]

+1 on the Marvel. Unstuck a Merc I6 outboard that had been sitting with it's case open outside (previous owner).
Also a 5.7 penta had the same treatment. In the past I've just poured hot diesel down and it's done the trick.

Best trick there is though...patience. Alas it doesn't come in a bottle.


Sent from my iPhone using Tapatalk

 

[Coastiejoe]

I've used ATF in customers vehicles. Was able to get the piston out and run a hone in the cylinder.. Good to go..

 

[Mickirig1]

What about heating them up with a torch? Heat the outside and lube the inside.

 

[rooster18]

I'll give a +1 on the marvels and ATF.


Sent from my iPad using Tapatalk

 

[Spimothy Leary]

thanks boys, i'll pick up some ATF and I have marvel at home already.

 

[Minnetonka4me]

my favorite tool if theres space...a sawzall...lol

 

[Sportster-2001-951C-Stock]

There should be enough piston clearance for just about any penetrating oil, I'd guess the crank should maybe turn just a hair unless a bearing is seized?

50:50 ATFin acetone is better than the expensive stuff but ATF by itself should be about as good as it gets in this case.

A block of wood as large as possible to spread the force out to the OD and a 2lb mallet can help if you have to beat on it.

 

[Dannyjd]

I use synthetic atf with a modified airline fitting into the spark plug hole. A couple days with 150psi in the cylinder has never failed me with a rust stuck engine.

Sent from my ASPERA_R6 using Tapatalk