3.5 Prop Shaft Assembly Choices?

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jaxracer

Well-Known Member
Joined
Jan 17, 2005
Messages
767
As the title states, what 3.5 prop shaft assembly choices are out there now? Before you guys get started, I know the OS is the best prop shaft assembly period, BUT I have an older Lawless that still uses the old style K&B threaded assemblies.

I currently have a K&B prop shaft that I'm using, but the stub shaft that the prop slides onto is a little short for some of the props I'd like to try so it prevents me from being able to tighten the prop nut beyond just a couple threads.

So what's out there and do any of you know if any have a longer stub shaft than the K&B uses?

Thanks,

-Mitch
 
That works, or get with Otto for the Nitro Water Sports ones that I used to sell. He sells them now, and they work pretty darn well.
 
As the title states, what 3.5 prop shaft assembly choices are out there now? Before you guys get started, I know the OS is the best prop shaft assembly period, BUT I have an older Lawless that still uses the old style K&B threaded assemblies.

I currently have a K&B prop shaft that I'm using, but the stub shaft that the prop slides onto is a little short for some of the props I'd like to try so it prevents me from being able to tighten the prop nut beyond just a couple threads.

So what's out there and do any of you know if any have a longer stub shaft than the K&B uses?

Thanks,

-Mitch
Mitch,

As long as the old threads are still in good shape Fred can usually re-tap for the correct reverse metric threads to accept the OS 3.5 prop shaft assembly. He converted two of mine a few years ago and they still fit tight to this day. That would be my choice, as the OS run trouble free for years.

Wallster
 
As the title states, what 3.5 prop shaft assembly choices are out there now? Before you guys get started, I know the OS is the best prop shaft assembly period, BUT I have an older Lawless that still uses the old style K&B threaded assemblies.

I currently have a K&B prop shaft that I'm using, but the stub shaft that the prop slides onto is a little short for some of the props I'd like to try so it prevents me from being able to tighten the prop nut beyond just a couple threads.

So what's out there and do any of you know if any have a longer stub shaft than the K&B uses?

Thanks,

-Mitch
Mitch,

As long as the old threads are still in good shape Fred can usually re-tap for the correct reverse metric threads to accept the OS 3.5 prop shaft assembly. He converted two of mine a few years ago and they still fit tight to this day. That would be my choice, as the OS run trouble free for years.

Wallster
Really? I had no idea that you could re-tap the lower unit to accept the OS drive. That's great info to hear. Guess I'll probably go that route. Much appreciated guys.

-Mitch
 
I've had both Lawless drives, and Fred can do the OS conversion. The OS stub is MUCH larger in diameter, and requires the use of an adapter ring, since it doesn't have the reverse-taper to hold the two halves together when torqued down, but it seems to work OK.

Since I've discovered the Hyperformance part, however, I haven't seen the need to pay the extra $$$ for the OS, or have to deal with the metric sizing... Haven't had to replace a Hyperformance stub yet... The 7.5 sized ones have bearings in them, to boot... and the prop shaft length on the 3.5 units is longer than the equivalent K&B parts, so you have a little more room for larger props...
 
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i prefer the ones otto sells. the hyperformance & the nitro watersports shafts both have extra length prop shafts. they both also have different depth square drive holes, so flex cable length may need to be adjusted. the hyperformance unit's reverse taper is very shallow & not exactly the right angle to match the lower. it may not stay tight, due to the reduced clamping force, & will need checked every run. the one from otto does not have this issue.
 
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