Curtiss Wright R-1820 prop nut size?

[wreck chaser]

I'm looking for the prop nut size for an R-1820 and the best method for removing it. I have heard about the "swench" that was used. I'm also looking at torque multipliers as I've heard this nut is torqued to 1500 ft/lbs.
I was told that the nut size measures 3.83" diameter on the flats so a 3 7/8" socket should be good. I want to make sure that this is correct before I buy the socket.

Anyone know of a surplus parts place to buy a socket from?

[AG pilot]

The "swench " you refer to, may be the part of the system that actually fits the prop nut, in a Sweeney torque ampifier.

The nut does not have flats on it, it is splined on the inside, or at least it is on the 43D50 prop used on a T-28.

The prop shaft extension is splined on the outside, in the same installation.

[robkamm]

are you doing this underwater? or did you pull it out? pictures please. there must be a ton of rust on it.

[51fixer]

Some variables here-
T-28s have a different variant of hub and the prop nut is different than the typical Ham Std 23D-50 that are much more numerous. Prop shaft size for the 1830 is 50 spline.
I install the props with a Ham Std Socket with a long 1" dia steel bar.
Book procedure is 180 lbs 5' out on the bar. Tap bar with a hammer to get a set of small holes to align for a pin that safeties the nut and stops it from backing off.
Nut on this type has 8 flats on it IIRC.
You have to remove the dome with its special tool, remove the safety lock pin device, remove the distributor which is a long alum chunk which carries oil to the dome and then you can access the nut.
Being more than 6 flats and the depth and location it has to be a special socket to engage the nut.
After breaking the nut loose the prop typically is stuck on the shaft on a modern install, it'll really take some force to remove it it is rusted or environmentally challenged.
The Sweeny device is quite expensive.
Somewhere in the Bald Eagle Thread is the prop install/removal. Probably several times over.

[wreck chaser]

Yes, motor is in a lake so it will be underwater with very low visibility.
Thanks for the information. I was about to order an expensive socket that wouldn't have fit.

So the tools that I will need is:

Special tool to remove dome.
A Ham Std 23D-50 prop nut socket.


Does the safety lock pin device remove without tools?
Does the distributor just pulls straight out?

I was looking at a torque multiplier for turning the socket but the Ham socket doesn't have a square socket hole does it?

[Rod Schneider]

On an intact prop, the dome has a small screw that is safety wired in place, acting as a safety for the dome ring. Once the dome is off, there is a wire clip down on the nut that has one end bent 90 degrees, which safeties the nut and the distributor valve. It can be removed with a common screw driver. The distributor valve unscrews--it has a hex section, but I don't recall the size. Then the nut unscrews, which will pull the prop off of the rear cone. In our case, we use a long bar inserted through holes in the nut socket along with some hits with a heavy hammer to break the nut loose. Under water may be a bit more "fun".......

[wreck chaser]

I appreciate the information.
My best bet is to find a prop nut and weld a square socket adapter on the rear so that I can use a torque multiplier which should easily break the prop nut loose.

I can also float the engine and prop into shallower water and try taking it off there but I'm trying to keep a low profile.

I need a large pontoon boat or barge type boat with a winch so I could get the entire assembly on deck and trailer the whole thing out.

[robkamm]

"I can also float the engine and prop into shallower water and try taking it off there but I'm trying to keep a low profile." interesting comment.

[Jay]

I have the prop nut socket as well as the prop shaft nut available. The price is 155.00 for the socket and 175.00 for the nut, both items "brand new". If you don't have a dome wrench, you can always use a drift punch to break the nut loose, then remove it by hand.

[Chuck Giese]

Sure, I'll hijack this thread, but it is related. I've got the Sweeney torque multiplier, I'm now looking for the correct socket and adapter plates for Ham-Std 23E50. Part numbers available if that helps.....

Last edited by Chuck Giese on Sat Jan 11, 2014 7:20 pm, edited 1 time in total.

[Chuck Giese]

On an intact prop, the dome has a small screw that is safety wired in place, acting as a safety for the dome ring. Once the dome is off, there is a wire clip down on the nut that has one end bent 90 degrees, which safeties the nut and the distributor valve. It can be removed with a common screw driver. The distributor valve unscrews--it has a hex section, but I don't recall the size. Then the nut unscrews, which will pull the prop off of the rear cone. In our case, we use a long bar inserted through holes in the nut socket along with some hits with a heavy hammer to break the nut loose. Under water may be a bit more "fun".......

Rod, as the prop nut unscrews, it will only back the prop off the rear cone IFF the hub snap ring is installed. I've come across hubs without them installed. This is for the 23E50 hub.

[wreck chaser]

"I can also float the engine and prop into shallower water and try taking it off there but I'm trying to keep a low profile." interesting comment.

There is a retirement community that lives by the lake. You can imagine if they see me trying to get the prop off.... there would be a golf cart traffic jam and 20 poodles humping my leg.

[Cherrybomber13]

Or the US Navy or Air Force