Snapped flex shaft after 5 runs

[simo71]

Hi all,

Well I have run my UL-1 now for 5 runs, today approx one minute into the 5th run...it stopped, thinking i had lost the prop. The boat got retreived, to find it spat the shaft from the stub shaft back.

I have lubed the shaft twice since it was first run using Quicksilver special lube 101 the stuff with teflton.

The thing is now i have lost a perfectly good Grim prop (40/53) apart from the flex shaft failure.

I would not expect the shafts to last forever, but as early as 5 runs? Anybody else had early failures?

Simon
Australia

[Fluid]

That is very short cable life. A few things to check:

Fresh or salt water running?
Sharp bends in the stuffing tube near the strut?
Remove and dry the cable after each day of running?
Store cable outside of the stuffing tube?
Broken end of cable rusty?


.

[simo71]

That is very short cable life. A few things to check:

Fresh or salt water running?
Sharp bends in the stuffing tube near the strut?
Remove and dry the cable after each day of running?
Store cable outside of the stuffing tube?
Broken end of cable rusty?


.

Fresh water.

No sharp bends anywhere including near the strut.

Have not removed the cable after each day of running (only been 2 days total or 5 runs).

Cable has been removed twice, the first time prior to first running the boat & the second time only yesterday for lube.

No signs of rust at all nor corrosion, very clean brake.

No binding at all, I do check this prior to each run before installing the packs.

It really has me stumped as to why it did snap, the boat has been a dream to run up until now.

[Steven Vaccaro]

Hi all,

The boat got retreived, to find it spat the shaft from the stub shaft back.


Simon
Australia

Just to clarify, it broke right at the shaft? It could have been a poorly aligned flex to prop shaft solder joint.

[egneg]

Did you have adequate clearance between the strut and drive dog? It should be the same as the prop shaft diameter.

[VIKOS]

So it should be the same diameter from the dog. Wow didn't know that. This whole time I've been trying to figure out why there was a Lil gap and not flush. Good to know then in that case.

[forescott]

Absolutely! That is the most common cause of a snapped shaft. That flexshaft needs room to shrink after it spools up.

[simo71]

Just to clarify, it broke right at the shaft? It could have been a poorly aligned flex to prop shaft solder joint.

That's very possible, though from removing the shaft twice I did not notice anything out of place or alignment.

As for the drive dog gap? really hard to say now.

[LarrysDrifter]

Call Hobbico and talk to someone there about it.Could have been a factory defect.Maybe they will send you a new shaft.And buy an upgraded shaft from here either way.That way if Hobbico sends you a new shaft,you ll have a spare while you run the upgraded shaft.

[simo71]

Call Hobbico and talk to someone there about it.Could have been a factory defect.Maybe they will send you a new shaft.And buy an upgraded shaft from here either way.That way if Hobbico sends you a new shaft,you ll have a spare while you run the upgraded shaft.

That's all I can put it down to. Still really *!***!***!***!**y I lost a perfectly good prop though.

[simo71]

I emailed Aquacraft a couple of days ago, still waiting for a reply.

[LarrysDrifter]

Flex shaft

I emailed Aquacraft a couple of days ago, still waiting for a reply.

Call Hobbico.217-398-8970.On the automated menu,press 5.Thats the Aquacraft extention.

[simo71]

I still have had no luck, I would like to think that Aquacraft where a bit more proud than this. I guess i should forget it about it seeing as though I have a "better" shaft on the way.

[longballlumber]

The gap inbetween the strut and the drive dog is very important and is listed in the instructions...

Was your prop sharpen and balanced correctly? An out-of-balance prop will also stress the entire drive line too.

Later,
Mike

[simo71]

Speaking with one of the people I go boating with said that this was first checked prior to launching the boat for the first time....He done this, hence why was unsure of the gap myself.

I purchased the 40/53 with the boat & the main reason why I went for that prop over the 40/57 is due to it being pretty well balanced out of the packet...Well that is the advise i did receive.

I have since purchased a new flex shaft along with another 40/53 prop.