break loose siezed piston

wondering if anyone out there has a way to break loose a piston that is seized. The chainsaw has been sitting for a long time. Looking through the exhaust port it does not look like it is stuck because of overheating or lack of oil. It may have had moisture in it I'm not sure. Any thoughts would be appreciated as I'm trying to restore this say which is a david bradley.

Start with ample penetrating oil down the spark plug hole and let it work for a while. Have had luck with dowel and a hammer

Kroil.

I've seen rings rust and stick a piston. Soak it with penetrant through the exhaust port and the spark plug hole. Kroil is great stuff.

Someone mentioned fitting a grease nipple on a gutted spark plug and giving it a few shots of grease, It should work unless the ports are exposed!

darren_nh said:

Kroil.

Click to expand...

Kroil loosened up the (4) seized pistons on my old 1950 Case Model S that had been sitting in the bush for 5 or more years.

Through the years I've tried every penetrating oil that I could get my hands on and Kroil is by far the best that I've come across.

Recently I've read about another called Free Oil (www.freealloil.com), but have not had occasion to try it. If I ever come across it I will buy a can to try out, but I won't go looking for it since I've had such success with Kroil.

Someone once recommended ATF. Anyone ever try that?

Seems a little too thick IMHO.

Just last week I broke a David Bradley free with a grease gun. I was amazed
at how easy it was, It did not strain the gun at all. It only works until the piston uncovers the transfers, then you have to use elbow grease.
CSW

I have had good luck with PB Blaster.

zr900 said:

I have had good luck with PB Blaster.

Click to expand...

pb blaster?

I use marvel mystery oil (red and black bottle at Wal-Mart.) The grease gun trick works well too.

zr900 said:

I have had good luck with PB Blaster.

Click to expand...

Me too, at least on rusted bolts and such. Never tried it with a stuck piston, but I bet it'd work.

I've heard of using ATF on tractors and such. I think the thought process is the detergents and other additives in it helps break up the rust. I don't know if there's anything really to that or not.

Dad's broken loose a few tractors with just soaking with plain old penetrating oil and a dowel and a hammer.

litefoot said:

Someone once recommended ATF. Anyone ever try that?

Click to expand...

When I was a lad, I spent a few days taking apart a rusty 2 stroke Suzuki T200 with ATF. Pull heads, pour in ATF, next day beat on pistons with wooden stake and sledge hammer, put spacers under cylinders and beat some more... I don't think the ATF did much other than provide some lubrication.

Fill cylinder with Diesel fuel.

kevlar said:

pb blaster?

Click to expand...

PB Blaster is just my favorite penetrating oil. In the states it is found in just about all hardware, and auto parts stores.

here is a link.

http://blasterchemical.com/display.cfm?p=50003&pid=4

zr900 said:

PB Blaster is just my favorite penetrating oil. In the states it is found in just about all hardware, and auto parts stores.

here is a link.

http://blasterchemical.com/display.cfm?p=50003&pid=4

Click to expand...

Cool,thanks.

litefoot said:

Someone once recommended ATF. Anyone ever try that?

Click to expand...

Yeah, but only after making a 50/50 mix of ATF/Kerosene to thin it out a bit and allow it to creep into threads, crevices, etc.

Works well and I still use it for soaking.

Add a little heat along with your penetrating fluids ,no more than a couple hundred degs. ,heat lamp for overnight 6-8 hrs ,you would be surprised. Also good brand of rust inhibiting antifreeze has unstuck many marine engines in my time , I live in the Maritimes and the boat engines around here get stuck when laid up for the winter months if not oiled before storing them .
Pioneerguy600

Pretty much what everybody said already and lots of patients. Dont get in a hurry or youll break something. :biggrinbounce2: