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silverghost
01-07-2010, 12:24 PM
Several years ago I put a new OJ inboard/V-Drive 4 blade cupped Stainless Steel prop on my BB 454 powered inboard ski boat.
Out of the box this prop looked like a polished jewel .
My boat stays in the salt water for 5 months so I also used two camp shaft zinks.
The prop ran much smoother than the typical three blade bronze or NiBrAl props I had been using for many years..
Never had any cracks in these.
Low speed docking was also improved with the 4 blades.
When I pulled the boat at the end of the season i popped-off the prop with a puller and found 8 small cracks on the blade's leading edges.
Most were 1/4"or less; but one was 1/2" long near the center hub.
I called OJ & they told me to return it with my invoice.
Weeks later I received a new prop with no note from OJ.
This year I installed the new prop..
At the end of this season I found the same type of cracks had developed on the second prop.
What would have caused these cracks ?
Has anyone had any crack issues with Stainless Steel props, on I/O or Inboard/V-drives ?

I have one crack on this second prop that is 3/4" long near the center hub.
I am glad I did not throw a blade into the bottom of my hull ! I had a friend that had this happen with a stainless steel CVP prop on his Masercraft and it took a big chunk out of the bottom of his hull
Do you think these cracks are stress or casting related?
Any ideas ?
Thank's

MOP
01-07-2010, 01:37 PM
Two in a row the prop is of poor quality. I would see if you can atleast get a partial refund and go find another prop.

silverghost
01-07-2010, 02:03 PM
I have to agree with you on the OJ props quality~
OJ inboard props usually have a good reputation among Ski-Boat owners !
Mastercraft, Malibu, Tige', and others use OJ as OEM props.
This prop cost $450+
The CVP (Central Valley Propeller) SS Prop I also talked about was made in Mexico & I believe they went out of business because of SS prop failures!

MOP
01-07-2010, 02:43 PM
For way you the boat like you said four blade is the best, you may want to consider bronze. Bronze if damaged is a lot easier to repair and usually slightly cheaper to do.

Phil

silverghost
01-07-2010, 07:36 PM
Here is the second OJ SS inboard performance prop this spring before the season & 5 months in saltwater.

Walt. H.
01-08-2010, 01:04 AM
Three posibilities to cause your problem

1-Flaws in the casting from the same production run
2-Over heat treated making it brittle
3-Grade of stainless composition incorrect for propellers but good for manufacturing knife blades.

BigGrizzly
01-08-2010, 11:22 AM
Actually there are over 400 different SS compositions. Most need to be heat treated to live under boating conditions. One thing that causes this same thing on IO's is ventilation on acceleration and turns. On high elevations props with big power props last about 16 hours.

MOP
01-08-2010, 09:49 PM
Being a full inboard I still vote for Nibral! More forgiving and easier to repair if need!