enginehistory.org

[jsteele]

Hi all,
I'm a returning old member, was on for a year or two about 4 years ago. Now joining up again after organizing a bare-bones shop and beginning service on our museums' collection of radials. Currently I am finishing disassembly of an R-2800-77 for cleaning, painting, preserving and then swapping onto our Martin 404. Then I'll do the next engine,and then the third, and then turn to our two -43's, and then perhaps a 4360. It's kind of grandma's attic only with engines. Fun!

This first -77 has been a mind bender and pretty expensive, but we've managed to avoid buying too many "special tools" with one or two exceptions. Now that I'm down to the crankcase and crankshaft disassembly, though, I'm really stuck.

In order to disassemble the split crankshaft the P & W way, I have to have an armature called a PWA 3000, a serious metal-lathe-sized device that can hold the center power section while a rack and pinion assembly powered by a portapower hydralic tool (I kid you not!!!) spins out the connecting screw.

This is a problem as P & W hasn't made one of these tools in, oh, 60 years!

So I'm curious if anyone has a tool they'd like to donate or sell or loan to our museum, and/or if anyone has an alternate way to generate 20,000 psi on the screw joing the front and rear crankshaft. The "screwdriver" that fits the crankshaft connecting screw is called a PWA-3000 Det.25. Looks like an overgrown concrete hand drill or star wrench on steroids.

I'll try to post pics shortly. Anyhow, all advice welcome!




Best, John

Engine and Shop Flunky
Glenn L. Martin Aviation Museum of Maryland

[jsteele]

Still working on our Dash 77, stuck at crankshaft disassembly.

Does anyone have pictures out of a tool catalog of the PWA – 3000 armature?

Reference to a tool catalog I can procure would be great. Any help gratefully appreciated.

Best, John

[akambic]

I may be able to get a photo. I helped preserve two R-2800-43.

I reviewed all pages of our R-2800 documentation; no mention of the PWA - 3000.

I did find two hydraulic pullers listed for taking apart split cranks:

https://www.enginehistory.org/BBimages/PW_Tools001.jpg
https://www.enginehistory.org/BBimages/PW_Tools002.jpg

Tony

[jsteele]

Tony,
Thanks for the pics. I've looked for these and they come as part of a massive chainfall-suspended tool that clamps on the the front of the counterweight and PUSHES the pin out. From one of my commercial sources, the price (even if they had one), which they don't) was CONSIDERABLE. Like multi thousands. He said that he and the other salespeople always salivated when someone came in after those tools.

We'll figure something out.

Best, John

[jriend]

John,

Here are some partial pictures from a manual in my collection that I believe are of the PWA-3000 fixture you’re looking for. Mighty big piece of equipment.

Good luck,

JR

http://www.enginehistory.org/BBimages/R-2800CB_OH207.jpg
http://www.enginehistory.org/BBimages/R-2800CB_OH208.jpg
http://www.enginehistory.org/BBimages/R-2800CB_OH244.jpg
http://www.enginehistory.org/BBimages/R-2800CB_OH261.jpg