I lost my propeller after installing a ropecutter !

[JPS31]

Hi everyone,

Intending to sail to Indonesia, I bought ropecutters to fit my SD60 saildrives of my Yanmar engine 4JH80 (catamaran Lagoon 52). The propellers are Brunton Varifold with 3 blades.

So I bought a Darglow HYDROAXE from Brunton. After 2 days of sailing, I entered a pass quite tricky and had to use full power on my engine.. While anchoring, I noticed a problem on my starboard engine which power looked like very weak...
In fact I lost the propeller and the ropecutter which is quite strange..
Does anybody had such a problem ?


Thanks to share !


Jean-Pierre


www.sailingcatleya.blue

[tkeithlu]

One way or another that prop was not tight, or was not pinned after tightening. That could have originated in debris between the prop and the shaft, one or the other not being quite round, the nut having similar problems, the not not being torqued quite right, or the cotter pin being left off. It could even be that the rope cutter added enough length to the assembly that the prop didn't tighten on the taper. When you applied full power, you spun that sucker right off the shaft. I'm sorry that it happened.

So, start with a new assembly. Clean the shaft and get rid of any burrs. Be sure that each part snugs up with no rocking allowed. Get the proper torque figure for your shaft and use a torque wrench. Use a new pin the right size. In all, be sure that it's an assembly you can be proud of - no corners cut.

As an aside: When you torque a nut on a bolt you are using the bolt as a spring, and stretching it slightly, within its elastic range, so that it squeezes the items being bolted together. The correct torque for that is a characteristic of the bolt, not the items being squeezed. You don't torque more because you are squeezing something heavy.

Aside on the aside: A previous owner used 250 ft pounds when he tightened the lug nuts on my Jeep. He was adding oversized tires, so....NO. Lug nuts need about 100 ft pounds, completely independent of the weight of the tires. He risked having a wheel break off the axle by taking those bolts toward their plastic (stretched) range.

[fstbttms]

Originally Posted by tkeithlu

It could even be that the rope cutter added enough length to the assembly that the prop didn't tighten on the taper.

Umm... no. The OP's boat has saildrives.

[SailingHarmonie]

If the prop was taken off to mount the cutter (and I believe with this model it has to be) the answer should be obvious: It was not put back on correctly.

Now, to be fair to whomever did that work, saildrives have a anecdotal history of losing props, even those props mounted carefully by people who know what they are doing. So it MIGHT be a coincidence. But I don't believe in coincidences.

[JPS31]

Thanks to all of you for giving time to answer my post.


Unfortunately, I just got an email from the company which delivered the rop cutter confirming that they DELIVERED A WRONG PART. THE NUT WHICH SHOULD FIX THE PROPELLER ON THE SAILDRIVE SHAFT WAS DESIGNED FOR AN OTHER PROPELLER.

[BlueH2Obound]

So, they are are going to make it all good, correct? Pay for new prop, and cutter?

[boatman61]

Looks like they owe you a new prop and cutter..

[JPS31]

I am now beaching the boat for removing the rope cutter on the other saildrive to cruise safely...
I ordered and PAID for a new prop and the new nuts....
The story is not finished, I must be refunded for this order of course... Let us see if these companies , BRUNTON and DARGLOW are fair !