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outboard question

Old 06-20-2005, 09:14 PM
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addicted2rc9
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Default outboard question

I purchased a used Dumas Hot Shot last season and have not had a chance to run it yet. It needed quite a few mods from what i have read in these forums. I have added an adj motor mount
and much faster steering servo. But from what I have read here the center line of the prop should be inline or only slighty below the bottom of the sponsons. If i raise mine that high the steering cables are into the hatch, which i have notched out to get it as high as i have, but I am still about 1/4" lower than the sponson. Also the skag has been cut off of the lower unit, is this going to cause a steering issue? The weather is finally good enough to run now here but I am a little worried as to how it is going to handle. will try to post some pics but have never done so in here.
Thanks in advance for all your help.
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Old 06-20-2005, 10:33 PM
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Ron Olson
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Default RE: outboard question

Cutting the skeg off the lower unit wasn't a good idea, you really need it to turn plus it also helps to keep the prop from getting damaged.
That engine mount doesn't do much for adjustability, you need to go with a Du-Bro or Octura which will let you adjust the tilt also.
You might want to go with a ball-link setup for the steering, that will give you a chance to raise the OB a little higher.
Old 06-21-2005, 04:09 PM
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Default RE: outboard question

Yep, need that skeg back on there. Get some stainless steel and start making one or just buy a new lower unit.

And to assist you on the steering issue. Get the dremel out and start cutting away the back of the cowl. It doesn't need to stay there. With more open room, the steering arms will have plenty of room to move around with.

Ron, look a bit closer. It appears that is a Prather mount already there. It will give some +/- adjustment. But I'd change that out to either the Dubro or Octura mount as you suggest.
Old 06-21-2005, 11:57 PM
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Default RE: outboard question

I was looking closely at the shots but wasn't sure if that was a Prather mount on there or not. It looks like it was painted over. The Octura mount has more set-back than the Du-Bro, not much but maybe enough to help.
Is racing in the boats future or just playing around? I'd dump a C-note for the new Aquacraft Top Speed 2 tunnel hull. If you got one through Tower, there is a $20.00 coupon that you can use and that drops the price down even farther.
Old 06-22-2005, 06:00 AM
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Default RE: outboard question

Can't quite make up my mind on the motor size.. Addicted, what motor is that? It appears to be a 7.5, but the carb mount says 3.5.. I'm soooo confused!!! (it don't take much!)
Old 06-23-2005, 05:51 AM
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Default RE: outboard question

Thanks for the replys, yes i is an adj mount with both up/down and tilt adj. I have thought of forming a new skag from aluminum but how would i attach it. the mounting would have to blend into the lower unit smoothly right, or i could cavatate the prop. It is a K&B 7.5 but pretty old i think. Seems to run well though. Ron, is the boat you mentioned at Tower a pretty good one, will
not be racing just running for fun.
Thanks again for all your replys guys.
Old 06-23-2005, 06:13 AM
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Default RE: outboard question

Replacement lower end halves are $36 from K&B and display as in stock. This may be the simplest cure for the missing skeg. If you go this route, you might want to order a spare shaft at the same time. Here's a link to order 7.5cc outboard parts: https://shop.mecoa.com/shopdisplayproducts.asp?id=189
Old 06-23-2005, 07:03 AM
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ob nut
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Default RE: outboard question

I'd stick with the current boat if you are just going to play with no racing in mind. The TS2 is for a 3.5 motor, believe the 7.5 would be to much for that boat.

Prather made a kit for the 3.5 OB (don't know if there was a 7.5 kit) that included a replacement skeg that would mount on the cav plate with the skeg going down from the edge. It was not at the stock location. You could do this with your motor. The skeg does not need to be where at the stock location. I'd get you a pic, but everything is packed ready for a move to a new house.

Think the easiest and best course of action would to get a new lower unit.
Old 06-24-2005, 07:58 PM
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Default RE: outboard question

Thanks Piper for the link. I think i'll just order the lower unit halfs and be done with it. Ron, I saw on here some time ago you posted a link for a brass replacement prop shaft and bushing made by someone other than K&B for the 7.5 outboard but I lost the link. If it's not too much trouble could you post it again? It's supposed to last much longer than the stock unit i'm told.
Again guys thanks for all your help
Old 06-24-2005, 10:37 PM
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Default RE: outboard question

Brian Nelson is making those prop shafts. Here's a link to the shaft page: [link=http://nitrowatersports.com/DriveLine.htm]nitrowatersports[/link]

I was surprised, last mention was the 7.5 were due out soon. Guess soon is here and gone

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