rigger set up question / Fantom .15 question

[anthony_marquart]

I bet this is a common problem,...

My FF12 is sagging down the strights and accelorating in the turns. I'm guessing this is prop size or strut height problem. Suggestions?

Also, anyone with the Fantom Racing .15,.. I'm having trouble with the engine loading up with fuel. I can run the boat, bring it in, put it right on the stand to start and it's flooded! That is very frustrating! Also, where do you have the needle set?

Thanks guys...

 

[TomMoorehouse]

sounds like the low speed needle might be too rich causing the flooding on the shore and that it is too lean on the high speed needle causing it to sag on the straights???

 

[TomMoorehouse]

or maybe the pipe is too short???

 

[anthony_marquart]

Can you explain to me how the needle being lean would cause the boat to speed up in the corners?

Pipe is set as long as I can get it right now because I'm running a new, bigger prop.

 

[ClayGlover]

How does the plug's coil look? shiny or grey? What type of plug are you using? The motor is aircooled with the stock headsink right? Slide or rotary carb? What prop are you running? What % nitro?

The high speed needle must be set to run right before you can set the low speed needle where you want it. It may be over-propped and the rudder is helping to lift the transom in the turns. I've seen engines with to much water-cooling act like that, but being air-cooled, I don't think it's temperature unless you live in Alaska

You can fix the low needle after getting it to run right, having the low-end to rich is better than to lean. When you are running at planing speed on the water, the low speed needle has no effect anyhow. I have my low-speed needle turned all the way out. Some people cut it off completely. To set the HIGH SPEED needle on shore, you will be near the sweet spot when you give full throttle and the motor sags a second or two before it wants to scream. You may have to blip the throttle to keep it idling without stalling. If you try to get it to run like they run in RC cars, it will probably be to lean on the low end needle.

Try a prather S215 prop to start.

 

[Watercadet]

The flooding problem after a run sounds like the unburned oil in the pipe running back into the cylinder and hydrolocking. Can you decrease the header angle at all so the oil runs out? Perhaps you are compensatina for a false rich condition on the needle.

Adam

 

[Ron Olson]

Boy, this sounds familiar! I've got 2 Fantoms, 1 side exhaust and one rear exhaust in the .12 sizes. Yes, mine are flooding constantly with the tanks low in the hulls, lower than the carbs so you'd think that they wouldn't flood. These motors run like scalded dogs in a truck but I'm having too many problems also. I did pick up some head shims for the higher nitro and next I'm going to try a Nova Rossi carb that Izitbrokeyet sent to me. I'm trying some Merlin 2006 plugs too. I've been running the same props that I've ran when I had a Trinity/Picco in the boat, the same pipe and pipe length and just about everything else identical.

When the boat is speeding up in the corners what is happening is that the prop is getting higher out of the water allowing the prop to unload.

I'll keep you posted on what I'm doing. Maybe contact Jeff Schroeder himself at Fantom. He used to run boats a long time ago. Yeah, I kinda know him. I used to race trucks on his Parents property in Vicksburg.

 

[Ron Olson]

Anthony, I asked this question on another site last night and got this response, something that I had forgotten about. Check the low speed needle to see if it is bent. I did notice this on one of my carbs. It must be a common problem with them.

 

[Eric Perez]

Pipe is set as long as I can get it right now because I'm running a new, bigger prop.

What's this new bigger prop that you are running? Sometimes when you get in the corner the prop can cavitate due to the extra drag of the rudder, also like someone suggested the rudder could be lifting the rear end changing prop-height and causing it to slip more. Lots of stuff going on in the water so it's hard to diagnose whithout actually seeing the boat run.

Flooding on shore sounds like a low-speed needle problem, how open is your carb when you start it? How open must it be before it will stay running prior to the launch? These are going to be your indicators to see if the low-speed needle is set correctly. If you are running the carb more than 1/4 open to stay on idle then your low speed needle is open too much.

What starting meathod you using to start the boat?

If the engine does not want to idle, even after carb adjustments add a shim to the head.

Are you running rich or lean? The plug will tell you.

Install a brand new plug run a lap or two and bring it in inspect the coil

Dark plug bottom = Overheating

Shinny Coil = Running rich

Brown plug bottom = Very rich (takes a while to "clear out" the engine on shore)

Sand Blasted Coil = Optimum setting

Pitted Coil / Burnt out plug = Too lean (Also check for detonation)

 

[Don Templeton]

Anthony:

One of the things I have always done in preperation to starting an engine after a run or even before the first run is remove the plug and blow out the engine while pinching the fuel line shut at the end of the blow. Don't forget, you could also have some water in it from just settling to a stop with a rigger. Good idea to throw a towel over the head first. I'm sot sure but it could have been me that sprayed nitro in Rons eyes at the fun run. Guess I ought to follow my own rules. If So, sorry Ron! :wacko:

Don

 

[Ron Olson]

Don, I don't think that it was me that got fuel in the eyes. I'm kind of getting used to getting sprayed down! I break a rule that I know that I shouldn't do, that is looking over the top of a motor while cranking it over and not having a towel of some kind covering the plug hole.

Eric, you forgot one. Missing plug----you didn't tighten it back down! :blink: