Nibral props

[Kevin]

http://keys.craigslist.org/boa/3679721484.html" onclick="window.open(this.href);return false;

Would these props be a good deal? They are very similar to my bronze props.
I have 1 1/8 shafts but I recall they make inserts so accommodate larger tapered bores.
Is there any negative to doing that such as weakening the shaft?
I have never messed with nibral and wonder if they perform better.

[bob lico]

Kevin I am somewhat acquainted with props so here it is ; Nibral is the best prop. Material due to it's rigidity ,the stiffest by far next is bronze in your boat it matters a little more due to high speed diesels. The bore insert does not weaken or have any effect on the shaft strength .stop listening to the " know it alls" unless the heated a prop or two and peen it out on anvil. This is a decent price for the pair.

[Kevin]

I just called the guy. He is in Cudjoe Key for the week but the props are actually in Michigan. I knew I did not recognize those leaves as being from the keys!

[Carl]

Only downfall to sleeving the props is it is another area you can have an installation problem.

Normally you only have to think about key riding up...now you have a key and a sleeve that can ride or pinch preventing wheel from seating properly. But done carefully, fit without key 1st, marked and then installed with key verifying it went all the way home by reaching mark, your in good shape.
Also a bit more of a pain if swapping props underwater.

Nibral is stronger and can be made thinner, less friction, less deflection, more go!!

[bob lico]

Carl I give advise predicated on the person I am talking to Kevin is a talented guy he pm's me so I know he will do the right thing. Hub of the prop is the exact taper as the bronze sleeve you could hand lap with valve grinding compound first time you fit then there is no problem unless you are a smuck and attemp to put a square peg in a round hole. We are surrounded with these people and the future will be worst!

[Kevin]

Thanks for the advice guys. I could see where the underwater portion would be far more difficult. More parts to drop into the deep unknown.
I wish these nibral props had been where the actual listing was. I like to put my hands on something like that before I commit to buying. I will keep my eyes peeled though. Fortunately my prop guy is reasonably priced for making adjustments and he has always got me dead on with requested RPM's. I will be back to tweaking them again when the bottom is done. I figure if I get another 200 RPM I can have him throw some more cup into the bronze props and see what happens. I will be sure to post up the numbers when I am done.

[bob lico]

You got it more cup . Additional cup is a twofold advantage .for one more cup will " bite " more water taking advantage of the power of diesels while increasing fuel economy secondly you can adjust you best engine rpm keeping the exact peak torque of the engines to coincide with highest cruise speed. You may drop a little wot speed but your fuel economy will go up dramatically. Increase pitch is a no,no for decreasing rpm on a diesel ; a little more wot. Speed at sharp increase in fuel burn. Diesel could go to 5 bucks this year set the boat up for fuel economy.

[Carl]

Bob, I gotcha on knowing everyone on this site is talented...but what can seem obvious after the fact is not always so before.

Prop bushings get a bad rap because they are often installed incorrectly...sometimes done by a lousy yard monkey..other times an owner that just doesn't know or care to take there time to get it right. The blame gets put on the bushings, I hate to even suggest them as they have such a bad rap around here. My thought was not so much to teach...but to calm an unjustified bad rap.

Another thing...bushings require special step keys to make up the gap, not a bad idea to have a spare.




Kevin, I hear your anxiety about purchasing online were you cannot see and feel your purchase. It's alot of coin for a Chinese auction.

...and underwater is not that difficult, just need to be a little more careful and take your time. I have bushings on my boat. I have changed wheels dockside without much difficulty. Biggest downfall by me, I often only have about a foot or so visibility at dock.

[Kevin]

Thanks for the heads up on the keys. I saw some bronze and plastic bushings online and I think they came with keys.
I will have to see what the boat does after bottom mods before I pull the trigger on props.
It seems as though you just can't find nibral in less that 1.25 bore unless you get a ski boat prop with a 13 inch diameter!