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Outboard engines

Old 06-23-2005, 06:09 PM
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nzcivic
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Default Outboard engines

Hi

How to outboard engines compare to inboards in respect to cost & simplicity?

Anyone know of any other brands of outboards i have

O.S
K & B
Thunder Tigre

Thanks
Old 06-23-2005, 11:12 PM
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Ron Olson
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Default RE: Outboard engines

The O.S.'s are back again after a short absence and also a C-note higher than before. I think that part of the reason why they decided to bring it back was because of the problems while K&B was switching ownership. K&B still isn't back like they used to be and have had some problems with the first production runs. Thunder Tiger has also made a comeback but I haven't heard much since they came back out.
There is another 3.5 OB engine that show be making it's debut soon, the Irwin .21 . It was supposed to be on the market by now but it doesn't look like it for now.
Outboards are more of a bolt-on, hook up the throttle and steering linkage and go. Inboards take a little more work to install.
Old 06-23-2005, 11:52 PM
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Default RE: Outboard engines

Hello,

I was looking forward to having an outboard, and purchased a KB 3.5 SS for a tunnelhull. Motor ran fine after I figured out the fuel tank had to be as high as the carb, or it wouldnt draw fuel and stall near half tank. There is only one major drawback that I can see with this particular powerplant, and that is its stub shaft at the prop. It constantly changes pitch due to its fast wearing. Almost impossible in my opinion to keep a steady trim setting. And they are not cheap to replace. Sure there are tricks to getting them to last, but why should we be left up to that. Where is the sealed lower unit with bearings that it NEEDS. This aspect of K&B's O/B's has pretty much ended my pursuit with them on tunnels.
Old 06-23-2005, 11:56 PM
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ejp67
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Default RE: Outboard engines

Do you have a pressure line going from the exhaust to the tank???? Do you ever grease your flexshaft??
Old 06-24-2005, 12:27 AM
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Default RE: Outboard engines

Yes, I run fuel pressure. Its just that the "pipe" that comes with the SS simply has no pressure. I have even went as far as trimming the excess pressure tap threads inside the muffler to a scoop shape and pointing it towards where I think has the most exhaust blast.

I have tried the ideas out there for sealing the lower unit, and also oil feeding it. It just seems the output shaft materials just dont cut it. The stub shaft assembly is simply in my opinion just a low tolerance piece of production budget, and only gets worse from there as you use it.
Old 06-24-2005, 05:25 PM
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nzcivic
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Default RE: Outboard engines

Thanks for the reply, Do you know if Irwin engines have a website?
Old 06-24-2005, 10:49 PM
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Default RE: Outboard engines

Irwin does not have a web site. Do you want a stock motor or mod? For 3.5's powerplants, there are Nova Rossi, Rossi, CMB, MAC, ?.. These will all bolt up to a K&B lower unit. If you don't like those, then there are Lawless or Irwin (if you can find them). All motors listed above will bolt up to these also.

Jetpack, put a hopper tank in there.. A 1oz tank on top of a 6 oz would work great. If not, make a mount to get it higher..





btw, that "pipe" on a SS is a muffler, not a pipe. I can run a full tank out without problems.

Prop shafts are a pain. Get replacements from [link=http://nitrowatersports.com/DriveLine.htm]Nitrowatersports[/link]. 1000% better than the stock K&B's.
Old 04-04-2006, 02:48 PM
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Default RE: Outboard engines

Bummer, they only make the stub shaft kit for the 7.5, i have a 3.5. The hopper tank is a good piece of advice, ty Mark...BTW what are you using for your rod end linkage? I havent seen those before.
Old 04-04-2006, 03:04 PM
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Default RE: Outboard engines

Mark, Jim is picking up his hopper tanks this week as it seems like Sullivan has about 2,000 of them ready for him to pick up.
Those rod linkage ends are another product of Sullivan's. I got turned onto them last year myself, they are nice! If you get some, notice the notch in the sleeve that goes under the ball otherwise they don't fit well at all. You'll think that something is wrong.
OK, well I did.........
Old 04-06-2006, 12:43 AM
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ob nut
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Default RE: Outboard engines

ORIGINAL: jetpack

Bummer, they only make the stub shaft kit for the 7.5, i have a 3.5. The hopper tank is a good piece of advice, ty Mark...BTW what are you using for your rod end linkage? I havent seen those before.
Those in the pics are Sulivan #S562. I also use #S560 for throttle control and #S905 for my fast 3.5 and larger outboards.

[link=http://www.sullivanproducts.com/ContSysAccMainFrame.htm]Sullivan Links[/link]

If you can believe this, Tower does not carry the #S905. Those are my favorites to use. 4-40 rods and ball joint. Get these thru your LHS. The others are 2-56 ball joints, perfect for throttle control or light use.



ORIGINAL: Ron Olson

Mark, Jim is picking up his hopper tanks this week as it seems like Sullivan has about 2,000 of them ready for him to pick up.
Those rod linkage ends are another product of Sullivan's. I got turned onto them last year myself, they are nice! If you get some, notice the notch in the sleeve that goes under the ball otherwise they don't fit well at all. You'll think that something is wrong.
OK, well I did.........
Ron, well, those are a bit hard to figure out

I've recently have recieved 3 lowers from Lawless, each equiped with the Lawless pressure oiling sytem that has the Irwin hopper tank for oil storage. My 29" doesn't have the height to allow the hopper to fit. Instead I'm using an old Kyosho 1/8 scale shock tower. Went out last Friday to test. Jul, aka Wave Wakker, was there with his radar gun. One pass was at 56+mph. Most passes on that tank were around 52-54 mph. I was grin'n from ear to ear.. Brand new Mac 3.5 w/o mods, Mac 3.5 buggy head w/ 3 cooling fins, Lawless lower, Lawless pressure oil system, SPP pipe, s/b x440 w/o mods, Wildcat 65%, Tanks-2-U 10oz tank.

The setup:



Other side, close up:




Old 04-20-2006, 09:21 PM
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Default RE: Outboard engines

Mark,
That sure looks nice
Wish I lived closer where I could get ideas for making my rig look that good....
John

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