Seized Piston

[delmarrey]

Originally Posted by marc2012

Since it is flammable I would caution re heating.marc

I've use it after heating up rusted valve flange bolts. It'll flare up for a moment but doesn't continue to burn. It's the vapors you have to be aware of. When I ran the repair shop I would buy it in the 5 gl can.

Kroil is not that hard to find. Most industrial hardware store carry it.

http://www.schmeling.com/msds/kroil_..._kano_labs.pdf

[cat man do]

Originally Posted by delmarrey

Kroil is not that hard to find. Most industrial hardware store carry it.

Interesting stuff
While trying to see if it was available in Australia I stumbled across this.

Machinist's Workshop magazine tested penetrants for break out torque on rusted nuts.

They arranged a subjective test of all the popular penetrants with the control being the torque required to remove the nut from a "scientifically rusted" environment.

*Penetrating oil ..... Average load*
None ...................... 516 pounds
WD-40 ................... 238 pounds
PB Blaster ............... 214 pounds
Liquid Wrench ......... 127 pounds
Kano Kroil .............. 106 pounds
ATF-Acetone mix.......53 pounds

The ATF-Acetone mix was a "home brew" mix of 50 - 50 automatic transmission fluid and acetone. Note the "home brew" was better than any commercial product in this one particular test. Our local machinist group mixed up a batch and we all now use it with equally good results. Note also that "Liquid Wrench" is about as good as "Kroil" for about 20% of the price.
Kroil - Super Penetrant - OZBMX

[delmarrey]

The ATF-Acetone mix was a "home brew" mix of 50 - 50 automatic transmission fluid and acetone. Note the "home brew" was better than any commercial product in this one particular test. Our local machinist group mixed up a batch and we all now use it with equally good results.

I'll have to mix up a batch and take it down to the guys for a demo. It makes since though. Kroil looks a lot like ATF and a solvent. It sure would save a lot of $$$. They change out the air compressor every 3 months with 5 gal. of ATF.

[TassieBloke]

Hi Mark,

Looks like you getting lots of suggestions to get the piston free. What I have not read yet is what you intend to do once the piston is free...

It will be interesting to see what the extent of the corrosion is to the cylinder wall after these months. I personally would be grateful for a pic or 2.

Thanks.

[Ironhorse74]

Remember the piston pin runs in like with the crank. The strongest place to tap the piston is going to be above the piston pin bosses. Hate to see you knock a hole in the top of the piston.

Brad

[Ironhorse74]

Originally Posted by cat man do

Interesting stuff
While trying to see if it was available in Australia I stumbled across this.

Very interesting. I need to soak my stuffing box nuts. I think I will mix up a batch. Thanks

Brad

[Svsilvergirl]

Yup , what tassie said. The cylinder wall and Piston rings are probably damaged beyond use if the piston is seized. If its stuck down at the bottom of the stroke , this could be hard to see without dis assembling the motor.

[minaret]

Originally Posted by delmarrey

I'll have to mix up a batch and take it down to the guys for a demo. It makes since though. Kroil looks a lot like ATF and a solvent. It sure would save a lot of $$$. They change out the air compressor every 3 months with 5 gal. of ATF.

I'd try mixing it with something other than acetone. Acetone flashes off too fast, the whole point of kroil is to stay wet and "creep" into the fastener over time. I'd think the acetone mix would dry too fast. And acetone will also damage any seals or paint it comes in contact with. I'm sure anything else would too, but perhaps not as aggressively. Maybe MEK? I'm sure kroil's "recipe" has been carefully formulated to provide maximum penetration while not flashing too quickly. But I bet if you played around you could replicate it...

[Mark1977]

Well I was out yesterday and took the head off the other cylinder as well. The cylinder walls don't look too bad. I will take some pics when I go back out to her. We are getting 15 to 20 Cm's of snow today. That will give the PB-laster a few days to work. If the walls and rings look bad once I get it unstuck i will hone them out and replace the rings. (no big deal). I have learned another lesson about taking care of things before they get to this point. I now have to deal with this before I can get to projects I had planned to do. I will update with pics on Friday.