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Discussion Boards => On30 => Topic started by: old pilot on December 05, 2025, 09:31:39 AM

Title: assembly/dis-assembly instructions for O-4-2 Porter and 2-truck shay
Post by: old pilot on December 05, 2025, 09:31:39 AM
Good morning all,

I've been running these two engines for a while so its time to lube/oil and perhaps weather a little. I have the parts diagrams included with the engines but would like an almost step-by-step instruction sheet so I don't do something wrong and ruin good running engines. Any help/suggestions will be appreciated.

If you haven't guessed from my other posts, I'm not too mechanically inclined. My handle says I busted the aircraft and had a crew chief to fix it.

Happy holidays.

Old pilot
Title: Re: assembly/dis-assembly instructions for O-4-2 Porter and 2-truck shay
Post by: Tom_C on December 26, 2025, 08:24:55 AM
Sorry for the late reply.  The Shay is easier.  From memory, you'll pull the trucks off with one screw on each holding it to the chassis.  Then, the motor is inside that round bit in the center of the chassis and you can access the gears once you open that part up... I think the engine slides out with the gears on top, but don't recall.

The porter, I think, just has a plate on the bottom and the gears are inside that.

Here's a tutorial on the shay.  https://www.youtube.com/watch?v=f8umshcB1Ak&t=276s
Title: Re: assembly/dis-assembly instructions for O-4-2 Porter and 2-truck shay
Post by: old pilot on December 29, 2025, 01:37:49 PM
Hello, Tom_C.,

No problem on the delay. I'm just getting back to you due to a health issue which is wiping out all three holidays' celebrating. I will give your info more time when I am in better shape.

Thanks and Happy New Year.

Old Pilot