Friggin Land-lubber

[Speedway]

Question: MyMicroburst with Picco .67 runs great on land, Runs, Idles, Revs but when launched, Dies in the first 10-15 feet. I have a perry mixer but dont seem to have full control of the flow either rich or lean. Any suggestions would be great. Should i scrap the Perry? Am i missing something ?

 

[Russell Bear]

Maybe the props too big?

Pipe's too short?

 

[Speedway]

Prop is an X457-3. Its an Irwin Quite pipe but havent measured it. Would it really be enough to snuff the boat? I thought it would just not have as much peak Hp if it was off a bit.

Maybe the props too big? 
Pipe's too short?

70089[/snapback]

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[tracerbob]

Sounds a bit on the lean side. I run a Microburst with a Mac 67. I'm spinning a X457 3 blade and a pipe length of 11 1/2". I would ditch the perry mixer and pick up a BV or CMD third channel needle.

I always start and launch the boat on the rich side and lean it out once I'm under way.

 

[anthony_marquart]

What nitro content are you running? I had the exact same problem with a 67 microburst and a CMB 67. I was trying to run 25%. It just would not launch. I switched to 50 and never had another problem.

 

[Norm Doerr]

Maybe the props too big? 
Pipe's too short?

70089[/snapback]

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That is very common, Is the prop too big? Pull the pipe out. Is it sooo rich that when the water jacket sees water it puts the fire out? One thing that happened to me was my reciever took a dump. When we would launch the normally reliable boat it would go 20 feet and die. It turned out the radio would glitch when the engine hit a high rpm and set the fail safe off. It drove me nuts.

 

[Speedway]

Im Running 30% Niitro. I'll try and get my mits on some 50 or 60% to see if there is a diff. So it sounds like my Prop is fine and Im leaving the office not to go home and measure the Pipe length. I'll post shortly. Im just trying to get this pig to run and Dont really know if i need the Perry 3rd channel needle. Can i just run a regular dial-remote needle?????

 

[Speedway]

And the Pipe has a total length from Cylinder center to end of pipe of 14 inches. Way outa wack on the length???

 

[Norm Doerr]

And the Pipe has a total length from Cylinder center to end of pipe of 14 inches.  Way outa wack on the length???

70106[/snapback]

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Could be too long. My 67s are usually in the 11" 11.5" range. Just so you understand I am talking center of case to weld on pipe. You may be wayyyyyyy short if you are going to the end of the pipe. Set the thing at 11.5" by pass the needle with an old Kaboom needle then try it. Do one thing at a time. Is the engine fresh or does it have some hours on it?

 

[Speedway]

I measured from the center of the Cylinder to end of the Q-pipe where the weld is. Only a small bit (1/4 inch is after that where the exhaust comes out). The engine is totally new with an RPM rod.

And the Pipe has a total length from Cylinder center to end of pipe of 14 inches.  Way outa wack on the length???

70106[/snapback]

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Could be too long. My 67s are usually in the 11" 11.5" range. Just so you understand I am talking center of case to weld on pipe. You may be wayyyyyyy short if you are going to the end of the pipe. Set the thing at 11.5" by pass the needle with an old Kaboom needle then try it. Do one thing at a time. Is the engine fresh or does it have some hours on it?

70110[/snapback]

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[Eric Perez]

Maybe the props too big? 
Pipe's too short?

70089[/snapback]

​

That is very common, Is the prop too big? Pull the pipe out. Is it sooo rich that when the water jacket sees water it puts the fire out? One thing that happened to me was my reciever took a dump. When we would launch the normally reliable boat it would go 20 feet and die. It turned out the radio would glitch when the engine hit a high rpm and set the fail safe off. It drove me nuts.

70093[/snapback]

​

It's starting to get a little chilly in here. Do you think over cooling could have such an effect? When I changed plugs I went to a hotter plug and it seemed to help the engine???

How do you know when you are overcooling. My engine fell off the pipe and it was just motoring with the prop fully submerged. If it was overheating wouldn't it just quit? Also I checked the plugs and there is no sign of running lean.

 

[Norm Doerr]

Maybe the props too big? 
Pipe's too short?

70089[/snapback]

​

That is very common, Is the prop too big? Pull the pipe out. Is it sooo rich that when the water jacket sees water it puts the fire out? One thing that happened to me was my reciever took a dump. When we would launch the normally reliable boat it would go 20 feet and die. It turned out the radio would glitch when the engine hit a high rpm and set the fail safe off. It drove me nuts.

70093[/snapback]

​

It's starting to get a little chilly in here. Do you think over cooling could have such an effect? When I changed plugs I went to a hotter plug and it seemed to help the engine???

How do you know when you are overcooling. My engine fell off the pipe and it was just motoring with the prop fully submerged. If it was overheating wouldn't it just quit? Also I checked the plugs and there is no sign of running lean.

70116[/snapback]

​

Yup that is exactly right. When my 45 comes in I used to check it with an IR thermo watchamacallit . The head would be at around 180 and the coupler about 350 seconds after I shut it off at my feet. I got some tempil sticks and they indicated the same thing. Use the cold plug and restrict the water. Did it launch before and now it is not launching???

 

[Speedway]

First Time runnin It! I am going to try higher Nitro fuel and then a hotter plug. The motor never really got hot to the touch at all. I may just try a big friggin Sail if the Fuel and Plug dont work; Maybe just stand at the bank with my remote and say i have a record breaking submarine and its just "screamin" under the water.

 

[Norm Doerr]

First Time runnin It!    I am going to try higher Nitro fuel and then a hotter plug.  The motor never really got hot to the touch at all.    I may just try a big friggin Sail if the Fuel and Plug dont work;  Maybe just stand at the bank with my remote and say i have a record breaking submarine and its just "screamin" under the water.

70136[/snapback]

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Use about 55 percent. I would stay with the cold plug and just restrict the water. Run it on the rich side of the needle.

 

[Terry Flynn]

First Time runnin It!    I am going to try higher Nitro fuel and then a hotter plug.   The motor never really got hot to the touch at all.    I may just try a big friggin Sail if the Fuel and Plug dont work;  Maybe just stand at the bank with my remote and say i have a record breaking submarine and its just "screamin" under the water.

70136[/snapback]

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Use about 55 percent. I would stay with the cold plug and just restrict the water. Run it on the rich side of the needle.

70149[/snapback]

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Be sure to restrict the water on the out going side make it work like a thermostat.

that way there are no hot spots and water is still pushing through it. the best way that I found for restricting the water is useing a small wire tie you can close it off a little at a time. and it's cheep

 

[Speedway]

Thanks Guys, Neat Tricks and I'll try em!

 

[Eric Perez]

Maybe the props too big? 
Pipe's too short?

70089[/snapback]

​

That is very common, Is the prop too big? Pull the pipe out. Is it sooo rich that when the water jacket sees water it puts the fire out? One thing that happened to me was my reciever took a dump. When we would launch the normally reliable boat it would go 20 feet and die. It turned out the radio would glitch when the engine hit a high rpm and set the fail safe off. It drove me nuts.

70093[/snapback]

​

It's starting to get a little chilly in here. Do you think over cooling could have such an effect? When I changed plugs I went to a hotter plug and it seemed to help the engine???

How do you know when you are overcooling. My engine fell off the pipe and it was just motoring with the prop fully submerged. If it was overheating wouldn't it just quit? Also I checked the plugs and there is no sign of running lean.

70116[/snapback]

​

Yup that is exactly right. When my 45 comes in I used to check it with an IR thermo watchamacallit . The head would be at around 180 and the coupler about 350 seconds after I shut it off at my feet. I got some tempil sticks and they indicated the same thing. Use the cold plug and restrict the water. Did it launch before and now it is not launching???

70135[/snapback]

​

Boat is new so there is no true launch history. I cut the low-speed needle off, and repostioned the high-speed needle to be vertical, also triple sealed the high-speed needle with a piece of fuel tubing over the entire thing...and I'm running a water deflector (90-deg elbow) on the carb inlet. Now I can richen the engine to the point it will not even clear out. I know that the "golden" rule was not followed, I need to see what was the true driver was that allowed the engine to "richen up". That will follow this weekend for sure.

I finally got the engine running soooo rich that on the shore the temps would not go over 134F. I then tried an experiment and put a wet rag on the engine head. Every time the rag touched the engine it acted like it was going to flood. It did not mater what I did to the throttle, the engine would literally loose it's bite and start to drown out. I learned something new today:

Over cooling can cause the engine to act like it's too lean. Check the plug and if you do not see evidence of heat induced plug stress, reduce the water a bit and go test again.

-Thanks Norm!

 

[Norm Doerr]

Maybe the props too big? 
Pipe's too short?

70089[/snapback]

​

That is very common, Is the prop too big? Pull the pipe out. Is it sooo rich that when the water jacket sees water it puts the fire out? One thing that happened to me was my reciever took a dump. When we would launch the normally reliable boat it would go 20 feet and die. It turned out the radio would glitch when the engine hit a high rpm and set the fail safe off. It drove me nuts.

70093[/snapback]

​

It's starting to get a little chilly in here. Do you think over cooling could have such an effect? When I changed plugs I went to a hotter plug and it seemed to help the engine???

How do you know when you are overcooling. My engine fell off the pipe and it was just motoring with the prop fully submerged. If it was overheating wouldn't it just quit? Also I checked the plugs and there is no sign of running lean.

70116[/snapback]

​

Yup that is exactly right. When my 45 comes in I used to check it with an IR thermo watchamacallit . The head would be at around 180 and the coupler about 350 seconds after I shut it off at my feet. I got some tempil sticks and they indicated the same thing. Use the cold plug and restrict the water. Did it launch before and now it is not launching???

70135[/snapback]

​

Boat is new so there is no true launch history. I cut the low-speed needle off, and repostioned the high-speed needle to be vertical, also triple sealed the high-speed needle with a piece of fuel tubing over the entire thing...and I'm running a water deflector (90-deg elbow) on the carb inlet. Now I can richen the engine to the point it will not even clear out. I know that the "golden" rule was not followed, I need to see what was the true driver was that allowed the engine to "richen up". That will follow this weekend for sure.

I finally got the engine running soooo rich that on the shore the temps would not go over 134F. I then tried an experiment and put a wet rag on the engine head. Every time the rag touched the engine it acted like it was going to flood. It did not mater what I did to the throttle, the engine would literally loose it's bite and start to drown out. I learned something new today:

Over cooling can cause the engine to act like it's too lean. Check the plug and if you do not see evidence of heat induced plug stress, reduce the water a bit and go test again.

-Thanks Norm!

70398[/snapback]

​

I have had them sit on the stand wide open just blubbering away, (new engine) and I could GRAB the head. Then I would start dialing the needle and backing the throttle off until heat would come up and throw it in the water. Another trick Ackerman taught me to use on the tall props was too leave it rich until you get to the shore, as usual, then just before it is launched lean it out, as soon as the prop hits the water nail the throttle and back it off as soon as it gets up on plane. Then richen it up until it four strokes, then go the other way until it is lean and then go back to just the rich side of perfect. It took practice but I can get it done in one lap. BUT it took a long time to figure that out. LOL

 

[Eric Perez]

I have had them sit on the stand wide open just blubbering away, (new engine) and I could GRAB the head. Then I would start dialing the needle and backing the throttle off until heat would come up and throw it in the water. Another trick Ackerman taught me to use on the tall props was too leave it rich until you get to the shore, as usual, then just before it is launched lean it out, as soon as the prop hits the water nail the throttle and back it off as soon as it gets up on plane. Then richen it up until it four strokes, then go the other way until it is lean and then go back to just the rich side of perfect. It took practice but I can get it done in one lap. BUT it took a long time to figure that out. LOL

70430[/snapback]

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Ok I got it. So how do I do this without a 3rd-channel needle setup? :blink:

 

[Norm Doerr]

I have had them sit on the stand wide open just blubbering away, (new engine) and I could GRAB the head. Then I would start dialing the needle and backing the throttle off until heat would come up and throw it in the water. Another trick Ackerman taught me to use on the tall props was too leave it rich until you get to the shore, as usual, then just before it is launched lean it out, as soon as the prop hits the water nail the throttle and back it off as soon as it gets up on plane. Then richen it up until it four strokes, then go the other way until it is lean and then go back to just the rich side of perfect. It took practice but I can get it done in one lap. BUT it took a long time to figure that out. LOL

70430[/snapback]

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Ok I got it. So how do I do this without a 3rd-channel needle setup? :blink:

70464[/snapback]

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The old school way would be to go down three clicks at a time and burp it wide open. If it bubbers then starts to clean out go back to idle and feel the head. Keep doing this until it bubbers for a second or two then cleans out. Throw the boat in the water and put some heat in it. Bring it in and feel the head and check the plug. If you can grab the head and not burn yourself go after the water and restrict it. The idea is to throw it in a little on the rich side and once it heats up it should be just on the rich side of perfect. Remember if you change the nitro content it will throw off the setting, (more nitro go richer). Also a tall prop will make it run lean too. This is the way the old school guys taught me and it works. I think Gary Preusse still runs without the third channel to this day.LOL