.12 SPD Dynamite Engine

[Tunnelman]

I have a 26" LaserLine tunnel with a Dynamite .12 SPD outboard. Having problems getting the engine to run. It will not prime itself. I put my finger over the exhaust and turn it over which usually primes the engine but no luck. The fuel will not get up to the needle valve. if I put gas in the carb it will run just long enough to burn that out.

I've set the high speed needle to 2-1/2 turns and the low speed to 4 turns.

But, if I can't get the fuel to the darn engine I guess it's moot what the needle settings are?

HELP

 

[Jerry Dunlap]

The 15 Lazer Tunnel was distributed by Horizon Hobbies. They haven't been available in a few years, so it's hard to say if Horizon has any spare parts. Horizonhobby.com is the e-mail address.

JD

 

[Tunnelman]

Thanks Jerry.

Appears that looks are deceiving. Saw the tunnel and thought the profile looked sharp and bought it on-line. Being new to the rc boating sport, I did not however pay attention to the engine type. I'm familiar with K&B, but know nothing about the Dynamite. The needle value is even hard to locate.

Frank

 

[Pennywizz6]

If something goes out just try contacting dinamite themselves. They will help ya im sure. But Horizonhobbies, www.horizonhobbies.com (i think? <_< ) is their seller place :lol:

Phil :huh: B)

 

[Tunnelman]

Thanks Phil.

Having problems getting the engine to run. It will not prime itself. I put my finger over the exhaust and turn it over which usually primes the engine but no luck. The fuel will not get up to the needle valve. if I put gas in the carb it will run just long enough to burn that out.

I've set the high speed needle to 2-1/2 turns and the low speed to 4 turns.

But, if I can't get the fuel to the darn engine I guess it's moot what the needle settings are?

HELP

 

[rippinwater]

Sounds like a blockage somewhere between the bottom of your fuel tank and your carb. venturi. Disconnect your supply and vent line from the engine. Blow through the vent line to see if you can easily push fuel through the supply line, if you can then the problem is in your carb. If you cant push fuel through, then you need to back flush your supply line and clean out your fuel tank. If the problem is in your carb then you need to unscrew the fuel nipple from your carb. and you should find some sort of debris in there, spin engine to BDC an blow through the intake of the carb to clear the debris. Hope this helps.

 

[Preston_Hall]

I doubt this is the problem but, you have a leak in the fuel system.

Or...........most likely................

Maybe you are starting it backwards. Make sure the starter is rotating correctly. The polarity (red/black) is reversed to start an outboard.

 

[rhomodel]

But Preston with a glow engine it doesn't matter if you try starting it in reverse or not. Only with a gasoline engine with a sparkplug it matters as it has to spark at the right moment

Julius

 

[Watercadet]

Oh, no, no, it matters. There is the intake timing on the crank, counter balance, and oh yeah the prop will spin bas-akwards!!

 

[snowdog-2112]

I put my finger over the exhaust and turn it over which usually primes the engine but no luck. The fuel will not get up to the needle valve. HELP

I'm really surprised that no body caught this. The engine is not primed by putting your finger on the exhaust. That blocks the pressure you need to help push fuel into the carb. You prime the engine by creating a vacuum in it by covering the carburator air intake. This will suck fuel into the engine and VOILA, it is primed.

I am certain this will cure your engine starting woes.

Snowdog

 

[Preston_Hall]

But Preston with a glow engine it doesn't matter if you try starting it in reverse or not. Only with a gasoline engine with a sparkplug it matters as it has to spark at the right momentJulius

Keep thinking that.

 

[Preston_Hall]

I put my finger over the exhaust and turn it over which usually primes the engine but no luck. The fuel will not get up to the needle valve. HELP

I'm really surprised that no body caught this. The engine is not primed by putting your finger on the exhaust. That blocks the pressure you need to help push fuel into the carb. You prime the engine by creating a vacuum in it by covering the carburator air intake. This will suck fuel into the engine and VOILA, it is primed.

I am certain this will cure your engine starting woes.

Snowdog

Either way it's the same. All you are doing is creating a larger pressure differential. Low case pressure relative to tank pressure.

 

[Watercadet]

Keep thinking that.

ROLAMO!!!

 

[snowdog-2112]

Either way it's the same. All you are doing is creating a larger pressure differential. Low case pressure relative to tank pressure.

The way I was taught is the way I know. It works and it works well. I was sharing my experience as fuel flow into the carb seems to be his issue. Perhaps I should have gone on to say that he should try this first and if it doesn't work, try the other suggestions.

 

[Ron Olson]

OK guys, remember what exactly that we're talking about here. This is a .12 Dynamite and yes, you can still get the motors but the rest of the hardware may be a little more tricky. This thing only has a top speed of about 17 MPH on a good day. Power to the prop was from 2 belts with a jackshaft in between, not quite the best way to make an outboard.

You could bolt on a hot .12-.15 motor but it wouldn't be worth it, too much power wasted.

Oh yeah, it does turn normally, not backwards like the K&B's and O.S.'s. This thing ought to have a pull-starter on it.

(Update) This boat is on the cover of the December, 1998 issue of RCBM. JD has an article in there of the BBY Patriot. Anyway, the motor does indeed come with a pull-starter or you can use an electric starter on the flywheel like a plane. The kit had the option of getting it with or without a motor but did include a JR Python radio.

 

[snowdog-2112]

Bump

Tunnelman,

Latest update please?

 

[Tunnelman]

Hey guys,

finially got it started....it was a leak aroud the cap...the guy who sold it to me had tried to wedge the cap on it looked like so I removed it an put it back on straight , screwed it down and bingo...we have fule to the carb....and yes it will push the F1 tunnel about 17..2222 mph with a tail wind...hardly much fun.... I guess I was over zealous on how sharp it looked verses how fast it would run.....I'm into speed ...of course... so I guess putting a larger engine on this thing would be redundant. Any comments are surely welcomed as to suggestions.

Thanks,

Frank

:huh:

 

[Tunnelman]

OK guys, remember what exactly that we're talking about here. This is a .12 Dynamite and yes, you can still get the motors but the rest of the hardware may be a little more tricky. This thing only has a top speed of about 17 MPH on a good day. Power to the prop was from 2 belts with a jackshaft in between, not quite the best way to make an outboard.You could bolt on a hot .12-.15 motor but it wouldn't be worth it, too much power wasted.

Oh yeah, it does turn normally, not backwards like the K&B's and O.S.'s. This thing ought to have a pull-starter on it.

(Update) This boat is on the cover of the December, 1998 issue of RCBM. JD has an article in there of the BBY Patriot. Anyway, the motor does indeed come with a pull-starter or you can use an electric starter on the flywheel like a plane. The kit had the option of getting it with or without a motor but did include a JR Python radio.

Ron,

Do you think it would be worth it to put a larger Dynamite engine on the LaserLine. I guess it is possible to just buy a larger powerhead?? I like the looks of the boat but like you said...17 mph doesn't get it. And the dual drive belts...wow, didn't know it had that either!!! I guess that limits your speed options right there?? Thanks for your input.

Thanks,

Frank

 

[Ron Olson]

You could put a hotter .12-.18 motor on it but the turbulence from that bottom belt will give you cavitation problems I'm afraid.