Warner Engine Thrust Nut

[Dave Hadfield]

Hi,

In the "Old Guy" notes I've been able to accumulate regarding the Warner, Jack Polk recommended checking the thrust nut every 100 hours. I don't have any other guide or information about this.

Does anyone have a picture, or a better description of the prop/hub assembly? I have a Sensenich wooden prop on a Warner 185 (R-550) Super Scarab. (Fairchild 24W)

There's a small "click" in the movement of the blade that I don't like the sound of, and Stan the Mechanic has asked me to do a bit of research before he makes the drive to my airstrip.

Thanks,

Dave

[Cvairwerks]

Dave...the thrust nut should be held captive to the hub by a snap ring. To check the torque, remove the locking bolt from the nut to be able to move the nut. If it's got a click, I'd take the time to go on and pull the prop off and check the forcing cone for wear. It would also be prudent to go on and disassemble the hub to check for slipping between the hub assembly and the prop itself. Any "clicking" in a wood prop indicates that something within the assembly is moving. When you tear it down, be sure to keep the orientation of the prop and hub sections the same. There is a specific torque sequence for the thru bolts to keep from crushing the wood. Sensenich is supposed to be very good about providing the the info, as well as quick turnaround if the prop needs work.

[Dave Hadfield]

Thanks, CV. That's what I'm looking for.

If anyone else has anything to add, or any photos, I'd appreciate it.

Dave

[Avro Biplane]

Hi Dave,

PM me direct, I have just gone through a similar excercise with a 20 spline wooden prop and hub on a Jacobs. Some work was required in the centre bore of the wooden prop and I learnt a lot about old fixed pitch prop hubs!

Howard

[Wheels up]

Thanks, CV. That's what I'm looking for.

If anyone else has anything to add......

Dave

Thrust nut holds the thrust bearing in. A propeller nut holds the prop on.

Your Warner is like a Ranger when it comes to the propeller spline. They are short SAE #20. NOT the same as a Jacobs, Continental, or other over 200HP SAE #20's. This means there is about 4 or 6 hubs that fit. It also means there is NO ...repeat NO...front cone. Just a bronze straight bore ring. Much of the procedures for the two types of SAE#20's do not interchange. In fact, there is a Warner hub whose model I don't recall, that has the compression plate on the face (engine side) of the prop.

HUB CHART


Periodic re-torque of wood propeller hubs is mandatory.
SENSENICH CARE

You should dismount prop and hub assembly and verify the rear cone is indeed bearing on the aft face as well as the tapered centering face. This assures the splines of hub are not bottoming in the spline merge area of crank. This puts excess pressure on splines resulting in damage of crank or hub...or worse.

[Dave Hadfield]

Sure glad I asked.

Thanks, Gents. I won't get to this now until the weekend, but I'll take photos and document it.

It's a Warner 185K, with the oil pressure line for a CS prop (unused, of course). #6007A

Sensenich W86CA69

Dave