Prop Cone Locking Bolt

[jeffnick]

My 250 drive is a short hub and the shaft is not threaded for a cone locking bolt. I remember reading that there was a bulletin to drill/tap these shafts - the tab locking cones are not even available anymore. What thread size is the locking bolt? If I did thread the shaft would I be able to fit a long shaft prop?

 

[am_dew]

Re: Prop Cone Locking Bolt

My 250 drive is a short hub and the shaft is not threaded for a cone locking bolt. I remember reading that there was a bulletin to drill/tap these shafts - the tab locking cones are not even available anymore. What thread size is the locking bolt? If I did thread the shaft would I be able to fit a long shaft prop?

True that the tab locking cones are not available (new) any more however you could buy a new replacement cone (sans tab indents) and a spacer (has tab indents)...the two of them together will get you the same result as a tab locking cone.

 

[RogersJetboat454]

Re: Prop Cone Locking Bolt

From the Volvo Penta 280/290 Service manual (may be diffrent for your 250);


NOTE!

Short hub propellers (folding washer and cone)

will be replaced by long hub propellers (plastic washer,
cone, center bolt). When installing long hub propellers
on older sterndrives, the propeller shaft must be drilled
and tapped for use of cone with center bolt.
Use drill jigg ​

​

885149 to drill the propeller shaft eliminating

the need to remove the shaft from the drive unit
as follows:
1. Install drill jigg on propeller shaft.
2. Drill a 6.5 mm (0.255?) hole to a depth of 20 mm
(0.787?). Use cutting oil to cool shaft. Clean thorougly.
3. Usa a 5/16?-18 UNC taps to thread shaft. Clean
thorougly.
4. Install propeller, plastic washer, cone and center
bolt. Torque: cone = ​

​

110 Nm (81 ft.lb.), bolt =

​

​

22 Nm (16 ft.lb.)​

​

.

​

 

[jeffnick]

Re: Prop Cone Locking Bolt

Thanks guys. That clears it up. The short hub, long hub, threaded vs non-threaded shaft can be confusing.