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reforming nimbral prop

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ran up on a sandbar hump at slow speeds in the middle of the lake last week and disformed 2 cups on my acme nimbral prop, real slightly. There is no major noticeable unusuall vibration under load and the damage is minor but noticeable when you run your finger along the contour of the cup. Has anyone used a deadblow and a formed piece of wood or a sandbag to form metal to straighten out a prop. thanks

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Your best bet is to take it to a prop repair shop. There is more to just pounding out a small dent. A prop shop will repair and balance it for you. If your prop is out of balance it prematurely wears strut bearings and could lead to further damage. Also, you should inspect your drive shaft strut to make sure that is straight. Probably ok, if you hit the sand bar a a realy slow speed.

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I've tapped out a few dings in nibral & stainless props over the years. And I also used a file to remove very small burrs off the edges. It worked out pretty well. But the problems were never very big. Just remember that any significant change will put the prop out of balance.

A buddy of mine just bought an 08 Vride. He ran dozens of things by me before he made the purchase. Questions about a cover, stereo, tower, etc. He brought it home last night. It had a couple of issues. The heater has popped, probably over the winter. One hose on the water pump was still loose so it leaked. And the air hose on the blower was torn up. All pretty easy to fix.

So we take it out on the lake & as soon as he puts it in gear & throttles up to speed I notice a vibration. I ask him about the prop. He says it's brand new. I asked why there was a new prop on an 08 boat. He said the old one was mangled so the dealer swapped it out. Hmmmm...... I'm thinkin there is more damage up the line.... possibly a prop shaft?

I think for the tool steel prop shaft to be damaged, your Nibral prop would have to be wasted.

Edited by Bill_AirJunky
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I think for the tool steel prop shaft to be damaged, your Nibral prop would have to be wasted.

I think all the prop shafts are stainless.

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i've done more maintenance than skiiing so far this year...

...memorial day weekend, I'm pulling my nephew when a watersoaked log goes unnoticed and thump-THUD....

I cut the throttle and check the mirror and two 1/2's of the submerged log split side-side as the kid goes through the middle (the 12year old boy is fine, the 17 year old boat now has a lot of shaking going on)...

Feel underneath - and everthing is fine: Fins / Shaft / Prop / Rudder...

Idle to the ramp and remove the boat... clearly now we see that one blade of the prop is bent on the leading edge (cupped shape is inverted slightly)...

After consulting the local dealers (we are on a fishing bass-tourney lake) the best advise I get is that this can easily be bent back with hammers and blocks of wood... what the heck, let try it...

- we ran for about 40 minutes with the shadetree repair attempts; the vibrations were reduced with our attempt, but the boat clearly wasn't right (especially at 2000rpm)... so we abandoned skiing and ordered a new prop

- the new prop 13x13 (same prop as originally equipped) and I can tell you two things:

1) our boat never ran with this little vibration (there were a couple little dings on the prop when we bought the boat a year ago)

2) there seem to be no ill or lingering effects of our 40minutes of run time with the degraded prop

Final note: to check the shaft for damage, I placed a block of wood on the ground under the prop shaft with the boat on the trailer... I positioned the wood so that it came withing a fraction of the cm to the shaft and then rotated the shaft to look for "runout"... we did this at several points (right near the prop, right near the stuffing box/hull, at the midpoint) and the shaft was deadnuts straight (no observable runout).

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damage is minimal on the outer edge of the cup. there is no material missing Im not noticeing any vibration I think I will be able to get it close, the sand bag and a deadblow should get her back in shape. I dont have much to lose.

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