Anyone know how to convert 9.9 to 15 hp?

[DJ]

Re: Anyone know how to convert 9.9 to 15 hp?

I would want to be well below or above that crankshaft.<br /><br />Like an old instructor of mine said to us about two cycle Detroits when they "took off".<br /><br />"ALWAYS run parallel to the crankshaft".

 

[FlyBoyMark]

Re: Anyone know how to convert 9.9 to 15 hp?

Suzuki dealer told me that once, I don't 'member what brand or model outboard it was.....there was a cast stop on the carb to keep the butterfly from opening all the way. He said you had to either grined or cut it off or buy a new carb upper casting.

 

[Stream_fisherKY]

Re: Anyone know how to convert 9.9 to 15 hp?

Guys, <br />Thanks for all the confusing suggestions. I am truly lost. Just kiddin. Seriously however, your comments are both intriguing and appreciatted. I am currently looking for a 15hp carb for my engine. I have to either buy a 15 hp carb for mine or rebuild the 9.9 carb so I figure i'll buy one. Problem is they don't make them anymore. ****. Guess I'll have to do some searching. If anyone has any ideas please share. Thanks.

 

[Stream_fisherKY]

Re: Anyone know how to convert 9.9 to 15 hp?

FlyBoy<br />In your discussion about oil to gas mixture you struck a nerve. My engine tends to fowl plugs and i have noticed tremendous carbon deposits. Thing is that I am sure that i mix 50:1 which is what my engine calls for. What else could be causing my problems?

 

[smalloutboardsarecool]

Re: Anyone know how to convert 9.9 to 15 hp?

I have a question if I put a spark blug in the exust near the exit and wire it to the distributer could I burn off all that unused gas and have fire coming out of exust?

 

[FlyBoyMark]

Re: Anyone know how to convert 9.9 to 15 hp?

sailboaty...in high school where you one of those guys that tried lighting his farts in the shower room without underware on?

 

[FlyBoyMark]

Re: Anyone know how to convert 9.9 to 15 hp?

Stream_fisherKY........Do you troll or idle your engine for a long time, do you have the proper heat plugs installed, using good quality gas or some el cheapo brand, what oil are you using, are you mixing 16 oz. of oil to 6 gal. of gas, is your idle mixture screw on the carb adjusted properly, do you ever run the engine at WOT for awhile to clear the engine out or jus' part throttle, is the priming/choke system adjusted properly and fuctioning as it should, do you have the jets that belong in the carb (has somebody been fiddling with the carb?), have you ever decarbed the engine?

 

[Boatist]

Re: Anyone know how to convert 9.9 to 15 hp?

Stream<br />You should have no trouble getting that 15 HP carberator at any Johnson/Evinrude dealer. You can not modify the 9.9 carb to make it a 15. You have to replace the whole thing. The bore on the 9.9 is .625 and the 15 is .875 also the venturi is a little different. The jets for the 15 are also bigger. If you just put the bigger jets in the 9.9 you will have too much fuel and not enough air. Do it right or don't do it at all. Check out this web site and read section on Carberators.<br />www.pugetsoundanglers.org/Fishing%20Info/Johnson%209.9_15.htm<br />If your plugs foul make sure the thermostat is working. If it runs cold plugs will never get hot enough to burn oil off the plugs. You should not be able to hold your finger on head for more than about 3 sec. Also decarb the engine and then readjust the low speed idle. When you get that new carb should be fine. It will burn more fuel but also but also produce more power at top end. The cyl bore and stroke are the same for both engines. Good luck

 

[MGuckin]

Re: Anyone know how to convert 9.9 to 15 hp?

FlyBoyMark,<br />Back to that 2.8 motor. How did you get that punched out to 3.4? Being a cast aluminum, obviously capable of larger overbore but the amount required to achieve that size is huge. Sounds like a stroker to me. Just curious. Would be an interesting project for an IO sleeper.

 

[smalloutboardsarecool]

Re: Anyone know how to convert 9.9 to 15 hp?

I am in high school. Gon go blow me and my boat upow trying to burn all the leftove gas!

 

[FlyBoyMark]

Re: Anyone know how to convert 9.9 to 15 hp?

MG the block is available as an after market part from GM. It has to be resleaved and the stock 3.2 crank fits it with some clearancing. Most all of the cranks that are used in the 2.8 v6 are factory rated to 8,000 to stay together. The later aluminum heads off the front wheel drive cars with the splayed valves are much better than the cast iron ones used in the camaro inline engine. Of course we installed over sized intake and exaust valves. You have to use the lower part of the two piece aluminum intake manifolds of of the front wheel drive cars and adapt your own induction system to it whether it be injection or carb. We put alum. heads on a castiron block punched to 3.2 and dyno tested 350 ponies @ 7,000 rpm with 10:1 compression and a holly 450 small quad carb. pistons where custom cut down dia. and removal of some of the skirt too. Connecting rods were highly modified chromemoly cut down too. The aluminum block cost $2,500.00 list unless you got some friends at GM. We were thinking about putting one on these setups in a Pontiac little Fiero, one of the later models that actually used a 2.8. We estimated the car would do well over 200 MPH...A TRUE little American exotica......The engines we have presently are in an experimental stage for drag racing that we're running in a car prsently. These little babies have ENORMOUS potential, very small(18"-20" high) and only 200 lbs. without accessories. How about one of these little engines with a V drive in a bass boat that does over 100 MPH. So small it would fit rite under the deck in the rear of even the smallest fiberglass bass boats? It is concievable to even mount this type of setup on even a 14' aluminum hull boat. Most 40 HP motors weigh 215 lbs. We can build these engines presently for under $8,000.00 bucks with all the accessories attached.<br /><br />100 MPH.........Isn't that a scary thought????????????

 

[Stream_fisherKY]

Re: Anyone know how to convert 9.9 to 15 hp?

Sorry guys, i was out of town this weekend or i would have responded earlier. Number 1 - My engine ALWAYS runs cold. Never do the heads get hot. I just installed a new thermostat two or three months ago but May not have done it right. How should i fix this. Also, I do use normal grade gasoline and mix 1 pint (omc evinrude oil) to 6 gallons. Everything else seems to be right. However, when i check my plugs, the top one is particularly bad. I have bad carbon build-ups (gonna de-carb) soon, maybe tommorrow or tuesday. I think that's about it for now. Thanks for all the info and suggestions.

 

[Stream_fisherKY]

Re: Anyone know how to convert 9.9 to 15 hp?

Oh yeah. I run WOT most of the time. Hardly ever idle. My engine doesn't like to idle. The other day I cleaned the carb out, basic cleaning, but found a lot of milky cream like deposits. What is that? After cleaning it ran great for about 15 mins, then seemed to lose rpm (prolly about 500).

 

[FlyBoyMark]

Re: Anyone know how to convert 9.9 to 15 hp?

............you got water in your gas!(if its gooy) if your talking about jus white solid deposits, thats cheap gas. I suggest you get one of those BIG screw on water seperator filters and install it between your fuel bulb and engine.......PRONTO....... Anyway you look at it, your fuel system sounds like its on its way to being sludged up. Strong dose of Mercury "Fuel System Cleaner" sounds in order.

 

[Stream_fisherKY]

Re: Anyone know how to convert 9.9 to 15 hp?

I suppose that maybe the water that entered my fuel system sprang from the fact that I ran it for 12 hours in the pouring rain the other day. I had the hood off a couple of times, so maybe water got in when I took the hood off. I will keep a close eye on it for the next couple of DRY days. Thanks for the info, will definitely see what I can find.

 

[Boatist]

Re: Anyone know how to convert 9.9 to 15 hp?

Stream<br />If your motor is still running cold I would pull the thermostat again and make sure the rubber seal around the outside is good or replace it. Also check to see if it is closed or has something holding it open. Put it in a pan and see if opens at 145 degrees. If motor is always cold gas does not vaporise correctly and drags more oil into clyinders instead leaving oil behind to lube bearings.

 

[FlyBoyMark]

Re: Anyone know how to convert 9.9 to 15 hp?

Some of the Tempo plastic gas tanks with unitized fuel gage and fuel pickup WARP after a period of time and the neoprene gasket underneth does not seal anymore. When it rains, the water runs in on the top of the tank around this seal where it collects.

 

[Stream_fisherKY]

Re: Anyone know how to convert 9.9 to 15 hp?

Interesting comments. My thermostat is merely a small metal object with a spring in the middle. I don't have anything else, like the rubber piece that goes on the back of it. When i bought the thermostat it came in a package and it was the only thing in the package. Should i doctor something up for it. Also, i pulled the thermostat and it is closed. So it seems to be functioning properly in that regard.

 

[FlyBoyMark]

Re: Anyone know how to convert 9.9 to 15 hp?

Didja put it in a oven set to about 200 deg. to see if it opens? Does the thermo. casting/cover pinch it inplace or do you think it jus' rattles around in the block when the cover is in place?

 

[Hooty]

Re: Anyone know how to convert 9.9 to 15 hp?

I just bumped up a posting, "Two Cycle Enginges-How They Work" that has the website of a animated 2 stroke engine and tuned exhaust/ expansion chamber operating. It's really interesting.<br /><br />c/6<br /><br />Hooty