Hoping to get some advice on drive shaft breakage. It seems that I don't get a alot of running hours on my 1/4 inch flex drive shaft. My set up is on a CAT hull.
I try and re-lube before each day at the lake using a marine grade grease. The stuffing tube is of the teflon lined type and I think the radius to connect to the strut in minimal.
Any Ideas how I might increase the life of these drive shafts?

do you have a pic of your setup?? that would help in finding the problem ... Later Bill

:dash: Hi,
A pic would be great. You have not told us what quality the cable is and how it is breaking. Then weight have an idea how to help you.
Graeme

I didn't know there was a difference in quality, I just buy them from aeromarine. Breakage usally ocurrs under WOT and is located above the radius for connection to the strut. I will try and get pictures of the boat setup and broken cable.

Just wondering a few things...... and these will shorten the life of the flex cable regardless of the brand.

Are you running a lot of Positive or Negative angle in your strut?

Are your strut bushings worn?

Are you jumping waves or running in rough water were the prop is actually leaving the water and entering back in a speed?

And when launching are you reving the motor up and just setting/dropping the boat in, or giving it a forward toss at launch?

Any of these questions listed will shorten the life of any cable.
And there is plenty of other variables sure, these were just off of the top of my head!!

Rcer.

Thanks for the ideas.
My strut is vertical right now. I do need to check the bushings.
When I launch the boat the motor is at idle and I give it a small amount of forward toss, I then slowly increase motor speed, also I try too never accelerate or decellerate to quickly.
Most of the time the water is calm and I don't try and jump any waves, I figure you don't want to load and unload the prop.

Okay... well it seems to me that you are not inflicting any added stresses to the cable which usually yields in cable failure!! I mean you do have to run the boat and have fun right!! I hate to say this but maybe it was just a bad run of cables?? Are they breaking where they are silver soldered to the prop shaft or just any random place?

And apporx how long are these shafts lasting for you before failure?

Rcer.

The cables tend to last about 4 to 6 running hours, the latest was inspected and grease just prior to running the boat today and breaking.
Cables have never broken at the silver solder connection and appears to be at random places. I should also included that the cable is 15.00 inches in length.
Thx
again

Well I can say this greese is good and prevents rust and friction, so keep on that. But 4 to 6 hours is not much and a 15 inch cable is fine, by no means is that long.

I run a 28 inch cable in my hydro and it lasts well over 4 to 6 hours!

When you are slipping the cable into the stuffing tube is there a point where its not a smooth transition or bind that you can feel?

I am kinda lost on this one..... are you running a promod motor that is making good power/speed?
Your doing everything right!! Maybe you have too much power!!

Rcer

Hi,
I know this is probably a stupid question but is the lay (direction of twist ie. left or right) of the cable correct? (funnier things have happened) Also is the angle of the cable (where it bends coming out of the hull) to the strut excessive?
cya. Graeme