twin 67 rigger

[jeff baham]

after a four year sit on the shelf I decided to run my twin. well I purchased some h-38's from mark sholund h-38 -5.63'' (t.e.)cup, 5.29'' (c.o.b.)pitch,63.74 mm dia rt. side prop and the other is 5.63''(t.e.)cup, 5.29 (c.o.b.)pitch, 63.75 mm dia left side prop. and i purchased a set of mac product 13cc pipes, and they are set at 10 1/2 from plug to center of pipe.( weld) .well I tried six time and the boat would not go pass bouy one, I try richening it till it was hard to start. plus I was using old fuel to .

 

[Bob Morton]

Hi Jeff,

Try some new fuel. Pipes are to short. Go to 11..5. If you have a Boris meter set the carbs at 45.

Nails

 

[FloridaScaleBoater]

For sure, the above.

10-1/2" pipe length is what I run on my 45's

Old fuel also will drive ya nuts trying to make it happen..

 

[julianconde]

Jeff what motors are you running ?? 11 to 11 3/4 is where i find its the sweet spot. your propeller set up looks really good.. make sure that when you start the motor and you press full throttle it hesitates just a bit before it spins the RPM's up.. if when you hit full throttle on the stand and they scream immidieately you are way to lean my friend.. let us know what happens ok..

julian

 

[Will Gallagher]

What engines?

 

[jeff baham]

they are the cmb gold head evo 1 67's.

 

[brett english]

even with the pipes short the boat should run around the course, if the boat keeps dying before u hit bouy 1, heres a quick check list...1)check the fuel tanks for leaks

2)check your pressure lines, are they reversed?

3)make sure your not getting water in the carb through you boom tubes or cowl

4)are you too rich? loading the motors

5)props seems correct but they may need to be barr cut

ill tell you its a big challenge but well worth it...dont give up!! (for sure lengthen the pipes)

Joe W can add a few more tips im sure

 

[Will Gallagher]

are you dropping one engine or both? I would say check the tanks for leaks, and change out ALL of the fuel tubing. Add some fresh fuel and try again.....

 

[julianconde]

also fuel filters ensure they are clean as well

 

[Tom Foley]

Were the engines sitting in the boat for four years or stored properly all cleaned out and oiled up ? If the engines are a known good part of this setup then go back through the fuel system one part at a time starting with the tanks . somethings telling me its the tanks .Disassemble the needles and flush over a clean paper towel and see what you get , same with the tanks . If metal tanks flush VERY thoroughly after use !

 

[jeff baham]

thank's guys I will lengthen the pipe and get new fuel, plus recheck everything that was mention by everyone,

 

[julianconde]

jeff keep us up to date of whats going on buddy..

 

[ids987]

If you're using a failsafe, is there any chance you might have a radio issue; causing the failsafe to kick in ?

Especially if both engines cut at the same time.

Just one other thing to add to the list.

 

[Joe Warren]

I have never seen a Twin that We could not get running. Many others have included the checks to make above. Pull the pipes back to 11 1/2 - 11 3/4, check needles for trash, check the fuel filters & tanks for Trash, look to see if you have air bubbles in the fuel lines coming to the carbs while running?? Check to make sure the pipe pressure fitting are Full open ESPECIALLY if they are 90 degree fitting?? Dont rule out a possible water leak on a engine or both engines?? Dont rule out a Possible BAD throttle servo? If you think you may have a water leak??? Pull the water line off the rudder and make a lap and come back in... Struts dont need to be deeper that the rear sponson ? Is the boat set up properly? Front Sponsons attack angles?? make sure the low/high needles are cut out of the carbs. Make sure the fuel inlet and spary bars are open in the carbs?? Do you have a flow meter? The #1 absolute most important thng on a twin is to make sure the carbs are timed together 100 percent before anything else...... You cannot begin to tune a twin if the throttle openings on both engines are not 100 percent the same. if you have a flow meter? You would want to work towards a boat that both engines fuel mixture needles flow the same, The engines sound the same RPM.. and the plugs read the same in wire color and the ring around the plugs are the same color..... when you get all that you are in the Winners Circle. ITS NITRO Jeffery.. A little work but nothing like standing on the front stretch when the Twin comes Buzzzzzzzzzzzzzing around and getting a Free Smell of NITRO in both Nostrils !!!!!!!

 

[jeff baham]

since sunday I've been sick ,and had time to think about the twin , the twin was built after hurricane Katrina , and I had it running then ,then we lost our pond and I joined the voodooclub, about four years ago, so that mean the boat was sitting more then four year, back then I had the cooper hp pipe on it and they were set at 10 3/4 plug to first weld. the boat ran great then, so I called mark sholund ask him to add a little more pitch for more speed . well when he returned the prop's back to me, I set the boat on the shelf and start running gas boats because no one in the club was running nitro, now we have about four guys starting run the nitro again so I decided to run the twin. well a few mouth back I purchased a pair of mac. product 13 cc pipes and installed them in placed of the cooper's. now I have some fuel coming from technology hobbies so it maybe a few sunday from now before I can text. just a note i'm not a beginner of nitro been running it since 89. it's just when you get away from it you tend to forget. everything that everyone mention WAS checked. except for fuel ,

 

[Joe Warren]

Jeff When 1 engine has a problem it will drag the boat down and kill the other engine. I know your not a newbie. But twins are a little different to trouble shoot when it comes to one that will not make a lap.

 

[Buckshot]

I'm glad to see you back at it with the twin Jeff!

Hopefully you can make it to the May race in Dallas this year. We had a great turn out of Nitro racers last year and I think everyone plans on coming back this year plus some more. With all the twins popping up around TX, LA, & KS we gonna have a good time this year!!

 

[julianconde]

since sunday I've been sick ,and had time to think about the twin , the twin was built after hurricane Katrina , and I had it running then ,then we lost our pond and I joined the voodooclub, about four years ago, so that mean the boat was sitting more then four year, back then I had the cooper hp pipe on it and they were set at 10 3/4 plug to first weld. the boat ran great then, so I called mark sholund ask him to add a little more pitch for more speed . well when he returned the prop's back to me, I set the boat on the shelf and start running gas boats because no one in the club was running nitro, now we have about four guys starting run the nitro again so I decided to run the twin. well a few mouth back I purchased a pair of mac. product 13 cc pipes and installed them in placed of the cooper's. now I have some fuel coming from technology hobbies so it maybe a few sunday from now before I can text. just a note i'm not a beginner of nitro been running it since 89. it's just when you get away from it you tend to forget. everything that everyone mention WAS checked. except for fuel ,

Jeff we are not questioning your skills or what you know we are just trying to help buddy let us know what happens when you test ok.

 

[jeff baham]

gotcha Julian, we all need help now and then. buckshot, I was thinking of the sept points race in dallas,

 

[jeff baham]

which set of pipe would be better to use the cooper hp or the mac's product 13cc