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Mounting WW151 Prop - Stud question

edhunter

Well Known Member
Mounting a new WW151H prop on my IO-320 RV9A. It came with new studs and castellated nuts, with roll pins to secure the nuts to the studs. The manual says "installed the studs, torque to 47ft-lbs, then safety wire w/ .036 wire". Or something to that effect.
Problem is installing the studs in the crank, then torquing the nuts to the required 47ft-lbs does not engage enough stud to uncover the holes for the rollpins. See photo. Also the rollpins do not allow for safety wiring the nuts....
So I'd assume you install the nuts to the studs, install the rollpins, then torque the studs into the crank.... But wanted to check first here (since its Sunday) and then call WW tomorrow if necessary....
Help appreciated. ed
 

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Basically yes. It would be a standard male fastener with an integral head if there was enough room to install it. Thus, you “assemble” the fastener in place if that makes any sense.
 
Any torque needs to be added to the running torque, if any. Just a reminder in case that's applicable here.

Dave
 
Basically yes. It would be a standard male fastener with an integral head if there was enough room to install it. Thus, you “assemble” the fastener in place if that makes any sense.

Got it.... so then after assembly and final torque, do you remove the roll pin and secure w/ safety wire?

EDIT: Didn't realize the roll pins were hollow... understand to run the safety wire through the roll pins... Thanks.
 
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Never messed with a WW yet but I assume it’s like all the others, big time NO. Treat the roll pin like the safety wire/drilled hole in the head of a bolt.
 
Likely Similar to Hartzell and MT - but use WW Install Info !

I'm not a WW user or installer - but when dealing with propeller attachment to engines ALWAYS use Manufactures Installation Information.
Appears to be similar to Hartzell compact or MT MTV-12-B where the nut is placed inside a groove in propeller flange & the stud is then threaded into nut such that the hole for roll pin appears in slot at top of nut - be sure to center roll pin so that no pressure or interference is applied by the pin on the closed end of groove (see MT Prop Operation & Installation E-124 Rev-63 Excerpt page 53) which you can Google to find. I'll attempt to attach a cropped image excerpt. The roll pin is what locks nut to threaded stud & transfers torque for tightening to engine prop flange inserts. Always pass safety wire through roll pin after final torque.
 

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Usually the prop is supplied with the studs in the hub, the nuts threaded on and the roll pins installed. The prop is installed by slowly threading in all the studs. This is somewhat tedious as the studs have to be tightened all at the same rate. Once the studs are tight and have been torqued the sport of safety wiring then begins. The lock wire goes through the roll pin, it is always tricky to get the lock wire through one nut, reckon on an hour or so if you haven't done it before. Then mount the spinner back plate - fiddly - and finally the spinner. Stubby wrenches are useful for tightening the nuts.
 
Mounting a new WW151H prop on my IO-320 RV9A. It came with new studs and castellated nuts, with roll pins to secure the nuts to the studs. The manual says "installed the studs, torque to 47ft-lbs, then safety wire w/ .036 wire". Or something to that effect.
Problem is installing the studs in the crank, then torquing the nuts to the required 47ft-lbs does not engage enough stud to uncover the holes for the rollpins. See photo. Also the rollpins do not allow for safety wiring the nuts....
So I'd assume you install the nuts to the studs, install the rollpins, then torque the studs into the crank.... But wanted to check first here (since its Sunday) and then call WW tomorrow if necessary....
Help appreciated. ed

Where are the roll pins in your photo? Something doesn't look right in your photo. The roll pins should have been pre-installed in the bolts, IMHO.
It sounds like you put in studs, then added the nuts. In my experience, that's not how they should work. You're not adding nuts to a stud. You're installing "bolts" that have heads that look like a nut with a roll pin pre-installed.
If you have a different setup, then you can ignore this.:confused:

I went back and re-read your post. Did you remove the roll pins and then insert the studs? If so, you need to start over......

I apologize if I am mis-reading your post.
 
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You appear to have installed the studs into the engine prop flange first, then the prop and nuts.

You need to insert the studs in the prop, screw on the nuts, insert the roll pins to create a "bolt" then install the prop on the engine.
 
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