Removing piston from 1940's Atwood GD Glo-Devil

[rglauson]

I recently bought an Atwood GD Glo-Devil engine and am trying to disassemble it. The information I have seen generally says to remove the cylinder liner and then the connecting rod can slip over the crankshaft pin and the piston be removed. However, this particular engine does not seem to have a liner and I am not able to get the piston out? Any suggestions?

 

[Daniel Williams]

I found an old article -

https://sceptreflight.com/Model Engine Tests/Atwood Glo-Devil.html

It shows a cutaway view of the engine. It looks like the cylinder head gets removed, and then the steel finned cylinder, which extends down into the case as a liner below the fins, can come off, allowing piston removal. If it's all gummed up from castor oil, try some heat.
I'm a model airplane guy, but could never deal with control line dizziness. I stuck with RC.
Hope this link helps.
Dan

 

[rglauson]

I found an old article -

https://sceptreflight.com/Model Engine Tests/Atwood Glo-Devil.html

It shows a cutaway view of the engine. It looks like the cylinder head gets removed, and then the steel finned cylinder, which extends down into the case as a liner below the fins, can come off, allowing piston removal. If it's all gummed up from castor oil, try some heat.
I'm a model airplane guy, but could never deal with control line dizziness. I stuck with RC.
Hope this link helps.
Dan

Thanks for that. I didn't realize with the cylinder head had the three longer screws and there was no liner. That helps alot.

 

[rglauson]

Set the engine in the oven at 300 F for 30 minutes and the steel cylinder came right out.

 

[a41capt]

I found an old article -

https://sceptreflight.com/Model Engine Tests/Atwood Glo-Devil.html

It shows a cutaway view of the engine. It looks like the cylinder head gets removed, and then the steel finned cylinder, which extends down into the case as a liner below the fins, can come off, allowing piston removal. If it's all gummed up from castor oil, try some heat.
I'm a model airplane guy, but could never deal with control line dizziness. I stuck with RC.
Hope this link helps.
Dan

That’s a really unique updraft intake system! Twin rotary valves? I’m far from expert in areas of model airplane/boat/tether car engines, but that has to be quite different from the usual system.

Thanks for sharing,
John w