Freezing/heating stuck block

So sitting alone at the old farm on a -15* Christmas morning, got me thinking of the leftover f-1 I need to dismantle, and the flathead in it. I've always wondered about how well it would work to take a block in from sub zero cold, put a nipco heater or propane torch blasting on the block if you could get enough clearance to get it loose and get some oil in there? The theory being if you could warm up the block with the pistons still being frozen.

 

It's going to take awhile. What are you trying to accomplish? Are you trying to start the engine? Why not use a dipstick heater?

 

sounds like its worth a try---ive frozen king pins before- they go together a lot easier-- also on press fit balljoints if you freeze them first it only takes light taps from a small hammer to get them to seat in the control arm

 

Sounds like an idea to free-up a seized engine, where the rings are rusted to the cylinder walls. Never thought of using the temperature difference to help break the rust seal.
What do you think about putting some dry ice in through the spark plug holes, then heating the block? Trying to get the temp difference as extreme as possible, shrinking the pistons/rings while expanding the block. Then when you get things cookin', squirt the lube into the cylinders and start trying to turn the crank.

 

I'll be amazed if it works. I'm thinking you could have it all disassembled by the time you get enough hot/cold differential built up anywhere to make a difference in this case.

 

the heat will transfer thru the rings/ rust into the piston, just the opposite as when the engine is running. Worth a try though. Sounds like you still have the heads on, I've gotten them unstuck by pulling the heads, heating the entire cylinder with a torch and dripping candle wax from burning candle into the ring area, as the metal cools it pulls the wax down into the joint, just like it does with stubborn bolts.

 

I have used hot water to free a stuck motor. Woked at a place that had an oil fired hot water heater and used super hot water. The guys there used the water to free up rusted stuff all the time. Just hooked a hose up to the water neck on the intake, opened the valve, let the water run. Took 2 times. Motor turned aftrewards

 

Let's assume that the real challenge is breaking cast-iron rings from cast-iron cylinders. Since changing the temperature of the block is much harder than changing the temperature of the rings, I'd go with dry ice on the pistons (as recommended by Zerk, above). You'll have to cool the rings about 100 F to create a 1-mil gap between the rings and cylinder. If you're lucky, rust will insulate the rings from the cylinder so that you can develop the temperature differential needed.

Note that the aluminum shrinks at roughly twice the rate of cast iron, so the pistons should be pulling away from the cylinders so penetrating oil will be more effective if it's not too bothered by the cold temperature. A few blows with the sledge might help the rings break free, or help the penetrating oil do its thing.