If you have ever installed a constant-speed prop, you have probably encountered the captured bolts that have to be turned one twist at a time before going to the next one, and the next one, and the next one—all while holding the weight of the prop and making sure that nothing gets cocked. If the bolts (or nuts in the prop flange) are even slightly used, you might find a spot where you cannot turn them with your fingers—then you scramble for your short wrench to turn the bolt one flat—and endlessly repeat. Once all the bolts are snug (and the prop flange tight against the starter ring gear face), you pull out your torque wrench and crowfoot, all the time knowing that it really is not going to fit. Numerous homemade “long crowfoot” wrenches have been made, and if you do not have a way to weld one up, you have had to jury-rig something with a stubby combo wrench, nuts, bolts, and washers.
What the world needs is a good, comfortable 3/4-inch crowfoot with extended reach and the ability to “ratchet.” And Ace Aviation Supply has taken on the challenge!
There are others on the market, but nothing with an end that is shaped so that you can manually ratchet your way across the bolt. The open end is cut so that you can turn the bolt head, then slide it several flats to take another bite—it is quick and easy to use. The other end is a standard slotted 3/4-inch wrench to torque down the bolts once they are snug. The wrench has a 1/2-inch drive hole—if you have a 1/2-inch drive torque wrench, you are ready to go. If your wrench is a 3/8-inch, you will need an adapter—but they are cheap.
For torquing, the standard method is to put the wrench at 90° to the torque wrench—you can then use the proper torque value without alteration. If you have to use a different angle to make it work in a confined space, Ace has you covered—there is a scan code laser-printed on the wrench—just pull out your phone and the code will take you to a torque calculator—no fancy math required.
The rounded-off edges on the Ace wrench fit comfortably in the hand and were clearly well thought out with the mechanic in mind. For those who have to install and remove props more than once in the life of the airplane, this is a great addition to the toolbox!
Allen at Anti-splat aero makes a nice one as well and has for a few years! He is an RV guy as well. His are only 85.00 and have both 3/8″ and 1/2″ drives made in.
I disagree about the “nice one” part. That anti-splat wrench has sharp edges that cut into prop hubs. It’s an expensive repair (I believe mine was $2k). This one Paul wrote about is beautiful.
+1 for the Anti-Splat prop wrench.
Regarding a torque wrench for these props.
I have a SnapOn torque wrench which has a 3/4 crowfoot end; no need for an adaptor.
Got it from the SnapOn display at Oshkosh.
Much simpler than using an adaptor and calculations!
I agree, we bought the Anti-Splat prop wrench years ago. Works great. Why is the Ace wrench better, Paul?
For starters I would say the ratcheting action is a real plus.
FYI, the Anti-Splat has the ratcheting feature as well. Allen’s video about the tool explains it very well.
I agree the ACE tool is pretty and smooth. Not knocking the ACE tool at all, just trying to add to Paul’s article that there was already a similar tool on the market.
Thanks for pointing that out. I have a new Hartzell going on a new engine and as the costs mount up I have been looking for an alternative to the tool Hartzell lists in their install literature. Google came up with a price tag of $1,500 from Air Power for the TE150. Crazy!
I’ll have a look at anti-splat.
Hartzell’s part number for TE150 is BST-2860, 2026 list is $1,370. So, that Air Power price isn’t fully out to lunch; an RSF could get you one for less but that’s still pretty silly looking.