Props

[Compulsion]

Is there any maintenance required for Jab Timber props? I know to back off in the rain if caught out.

 

 

[Guest Andys@coffs]

All your questions answered here, and definitively where as forums arent.... http://www.jabiru.net.au/manuals

 

Andy

 

 

[old man emu]

Keep an eye out for delamination of the fibreglass covering over the surface of the blades. Also look for dings at the hub.

 

Don't forget that the rotation of the engine is transferred to the prop as a result of the friction between the prop hub and the crankshaft flange. (Poor description of the metal bit on the end of the crankshaft, but I forget the name of it). The prop bolts are just there to keep the prop in contact with the flange. So make sure you check the prop bolt torque (24ft-lbs) and look out for elongation of the prop bolt holes through the propeller hub.

 

Always leave the aircraft with the prop horizontal to the ground so that if it rains, water will enter the prop equally on each side of the hub. At the same time, make sure that any openings into the engine bay close to the prop are blocked off to prevent birds entering and making nests in the engine bay.

 

OME

 

 

[brilin_air]

So make sure you check the prop bolt torque (24ft-lbs) and look out for elongation of the prop bolt holes through the propeller hub.OME

24 ft-lbs is a bit tight, according to Jab manual, prop tension is 7 ft.lbs, prop flange is 30 ft.lbs

 

Brian

 

 

[Sapphire]

Prop torque is based on the size of the bolt. I had a Great American prop that just got thinner and thinner with retorquing. You need a special springy washer to keep the torque more constant.

 

 

[Guernsey]

Always keep the prop horizontal to the ground even when in the hangar.

 

If any moisture has managed to get into the wood previously then that moisture will tend to drain down inside the prop if it is left vertical and thereby throw the prop out of balance.

 

Alan.

 

 

[billwoodmason]

Those springy washers are called Bellville washers, the manual says 6ft lbs (72 in lbs) is the recommended torque value similar to that which Brian suggests.

 

 

[Alpi]

Mate here you go, saved the best advice for last !!

 

Use the maintenance maual.

 

You can't sign out in your maintenance log "Prop torqued in accordance with recreational flying forum"

 

 

[facthunter]

You can if you spell it right. Prop talked in accordance with recreational flying forum. Nev

 

 

[old man emu]

24 ft-lbs is a bit tight, according to Jab manual, prop tension is 7 ft.lbs, prop flange is 30 ft.lbs Brian

My apologies. Shot off at the beak! Never rely on your memory. Always check the published data. Alpi is correct..