Rotator gearbox output seal change

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nebraskaairboater
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Rotator gearbox output seal change

Post by nebraskaairboater »

I had stored my gearbox while I was putting my new boat together and finally got it going this weekend. Problem now is that the gearbox is leaking oil at the seal of the output shaft on the prop side. Is this something that can be changed without removing the gearbox from the engine? Would like to do the change myself or have a local shop do the work rather than sending the box in as i've lost a bunch of ride time already putting this thing together.
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Dan Porter, Jr.
Fremont, NE
16 x 8 1971 Flat Bottom Fiberglass Hull / 454 Chevy/ 2.38:1 OX Drive / 80" 3-Blade Sensenich S

rotator75
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Re: Rotator gearbox output seal change

Post by rotator75 »

Call Sam at Classic Airboats he can help you out.Good luck.

midwestairboat
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Re: Rotator gearbox output seal change

Post by midwestairboat »

Yes you can.
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Littlefella
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Re: Rotator gearbox output seal change

Post by Littlefella »

Nebraskaairboater I have the same problem as you did. How hard was the fix?

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nebraskaairboater
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Re: Rotator gearbox output seal change

Post by nebraskaairboater »

Havent had it fixed as of yet. I have the box off sitting in my garage just waiting for my friend who has the experience and equipment to find time to get it done.
Dan Porter, Jr.
Fremont, NE
16 x 8 1971 Flat Bottom Fiberglass Hull / 454 Chevy/ 2.38:1 OX Drive / 80" 3-Blade Sensenich S

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nebraskaairboater
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Re: Rotator gearbox output seal change

Post by nebraskaairboater »

Well my box is still sitting in my garage and it's almost time to start boating... anyone have instructions or tips to get the thing apart to change the bearings and seals? Figure I will change bearings while I have it apart. Fingers crossed that that is the extent of work I need to do to get it running.

Thanks,

Dan
Dan Porter, Jr.
Fremont, NE
16 x 8 1971 Flat Bottom Fiberglass Hull / 454 Chevy/ 2.38:1 OX Drive / 80" 3-Blade Sensenich S

shiggs
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Re: Rotator gearbox output seal change

Post by shiggs »

nebraskaairboater wrote:Well my box is still sitting in my garage and it's almost time to start boating... anyone have instructions or tips to get the thing apart to change the bearings and seals? Figure I will change bearings while I have it apart. Fingers crossed that that is the extent of work I need to do to get it running.

Thanks,

Dan
After unbolting your Sens. prop hub, heat the prop flange with acetylene or map gas to be able to remove the flange. Once that is removed remove the key on the shaft. Remove the bolts on the seal and run a razor blade under the seal flange to break the seal of the RTV sealant. Remove the seal. Put a bead of RTV on the flange that the seal will bolt to making sure you have the sealant on the inside of the bolt holes. Use tape around to protect for any sharp edges on the end of the shaft and slide your new seal on. Reinstall the bolts and torque down. Remove any tape if you used any on the output shaft and reinstall the key in the shaft. Heat your prop flange and reinstall until it rests against the shoulder milled into the shaft.

The bearing may be tough if you are not taking the box apart and driving the output shaft out through the bearing, because I believe it is sweated on like the prop flange.

Good luck with your repair!

Joe
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Re: Rotator gearbox output seal change

Post by Joe »

Do you have a vent hose on the top of the box or just a plug? If its not vented it will push oil out of that seal. Had it happen on my last rotator,put a nipple and a breather hose on and it quit leaking.
Compromise is for those that cant get it done!!

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nebraskaairboater
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Re: Rotator gearbox output seal change

Post by nebraskaairboater »

Thanks for the info... I do have the barbed nipple on the top for a vent. My box is pretty noisy so I figured while I have it off I'd go ahead and put new bearings in it if I had to pull it apart to change the seal. It seems like I can change the seal without taking the box completely apart by the instructions shiggs gave so maybe I will just replace the seal and ride. Is there a good way to figure out if I have a bad bearing without disassembling the box completely?

Dan
Dan Porter, Jr.
Fremont, NE
16 x 8 1971 Flat Bottom Fiberglass Hull / 454 Chevy/ 2.38:1 OX Drive / 80" 3-Blade Sensenich S

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