Author Topic: New FL350 owner needs help  (Read 7032 times)

W8kski

  • Newbie
  • *
  • Posts: 12
  • Karma: 0
    • View Profile
New FL350 owner needs help
« on: March 08, 2010, 04:03:27 PM »
I recently purchased an FL350 that a guy rebuilt from the ground up and it's about 95% done.  It cranks right up idles fine revs good and has 120 compression with a watercooled head.  When I put it in gear to ride it it will start to take off, then choke like it's going to die and then catch it's breath again.  I noticed that its gravity fed with a spun aluminum tank and no fuel pump at all.  I tried putting one of these on my old FL250 and it wouldn't keep up without adding a fuel pump or something.  Could this be the problem I'm having?  Doesn't this tank need a vent on it?  There's no vent on the cap.  This thing is pretty tricked out, and it's killing me to not be out riding it!

jim327

  • Newbie
  • *
  • Posts: 29
  • Karma: 0
    • View Profile
New FL350 owner needs help
« Reply #1 on: March 08, 2010, 04:15:07 PM »
I'll send you more as you need them on other things to do, just call


#2
             THIS IS THE 2nd MOST IMPORTANT THING TO DO ON A ODYSSEY!!!
This message will tell you how to Plumb fuel lines on ODY's using 3 different combinations, the first is for a stock Keihen on the odysseys or pilots and or a Mikuni usiing  2.5 Float valves.  The third is how to plumb the fuel lines when you are using a Mikuni with a 1.5 float valve.

       On all 250, 350, & 400 Pilots, ALWAYS MAKE SURE YOUR GAS LINES ARE NO OLDER THAN 5 YEARS OLD AND THE FUEL PUMPS EVERY 10 YEARS.

             On the pick up or negative pressure side of the fuel line system, you have to use only the FIBER REINFORCED BLK FUEL LINE, use 1/4" ON GAS LINES & 3/16 ON VACUUM LINE.  On the pressure side of the system, from the fuel pump on out to the carb (and if you have the T from there on back to the tank) you can use clear blue fuel line.   NEVER USE rubber vacuum lines or the gray fuel lines with out fiber reinforcement.
       
 
          This picture has a replacement T with a metering jet in the T where the line goes back to the fuel tank. You can also add a check valve in the line that goes from the T on back to the tank, this will keep the fuel pump from loosing prime.  

 
 
              The side of the fuel line system that is on the negative or vacuum, which is from the petcock to the fuel pump needs to be a 1/4" inch fiber reinforced fuel line.
               The same goes for the vacuum line that make the fuel pump operate, only that this line should be a 3/16" inch fiber reinforced fuel line. This is actually the most important hose to replace as soon as possible!
                 Now on the positive side pressure, that is from the fuel pump on out you can use the clear or blue clear lines that have no reinforcements.
 
* HOW TO CHECK THE HONDA PRESSURE T THAT DIVERTS GAS TO THE TANK
          To check the HONDA T, hold it to your mouth with the pressure valve pointed away. Put your thumb on the bottom of the T and blow. IF it blows easy but you can not suck in, just like a check valve ITS BROKEN!!  When you blow it should not allow you too until you build allot of pressure up. Then it will continue to blow with heavy resistance and lock up before you can come near running out of breath, that is a good working T.
 
           THIS APPLY ON ALL THREE 250 - 350 - 400'S
 USING THE ALUM. TANK W/ KEIHEN CARBS
           When you are using the stock Keihen Carb or any Keihen Carb you will need to mount a chromed valve stem into the neck of the alum. tank.  After you mount valve stem remove the center core and then you can hook the 1/4" return fuel line back into it.

      ADD THE CHECK VALVE IN THE LINE GOING FROM THE RETURN T TO THE TANK !! This will keep the fuel pump from loosing prime.
 
THE Basic system is the same as above, you just have to remount your fuel pump anywhere you like. The fuel pump can be upside down to right side up, it doesn't matter. Just remember to use a 3/16 fiber reinforced line to run it.  
 
NOW I HIGHLY SUGGEST THAT YOU NEVER USE THE GRAVITY FEED SYSTEM!!!
          When your using the stock carb or any or all Keihen carbs they all have the seat of the float valve (needle & seat) pressed into the body of the carb. Kehien uses a 2.5 float valve that is in the middle of no where. It is to big for you to be able to run the fuel line direct, if you do it will flood the carb. 2.5 is to small to gravity feed
            To gravity feed HAVE TO HAVE A 3.5 or a 4.0, with the 2.5 you will only lean your fuel and damage your top end when you make more than a 200 yard dash or further at full throttle. That is because a 2.5 is the same as having a 1/32" hole, so it will not keep up with over 1/2 throttle.  
           
       The problem is that even when you use the proper sizes, 3.5 or a 4.0 float valve when using the Mikuni carb is that after you burn off the first gallon of gas it will begin to slosh side to side. That will only leave aprox. 2 inch's of gas in the center over the petcock. Now 2" is not enough weight to push the gas through a fuel filter and keep up with your carb when over half throttle or you will run your fuel bowl dry, even if it is for only a few seconds, it only takes 20 seconds to damage the rings and soon after you do it over and over you will more likely burn another piston out.
.
                         PLUMBING THE MIKUINI CARBS
 
IF YOU REPLACE YOUR CARB USING MIKUNI CARBS WITH A 1.5 OR THE 1.8 FLOAT VALVES
         USING THE MIKUNI CARBURETORS IS THE BEST FIX that you can use to replace the stock Keihen or any Keihen carb. In the Mikuni TM carbs you can change out the float valves (needle & seat) to a 1.5 and that way you can run the fuel line directly from pump to carb WITH NO T's.
 
Using the Mikuni carb you plumb your carb this way:

       We use the 3/16" fiber reinforced line for a vacuum line. The line from the petcock to the filter and from the filter on to the pump is a 1/4" fiber reinforced fuel line. From the fuel pump on to the carb you can use the clear or the blue clear fuel line.
ALWAYS use the stainless steel radiator style hose clamps, not spring or wire clamps, on all the fuel line ends.
 
            WHAT TO DO WITH WHERE THE FUEL LINE RETUNED INTO THE TANK
          Where your return line use to return on the top of the tank will not be needed anymore now. What most people do is to install a new 1/4" fiber reinforced fuel line to the old return line inlet, that will be used now as a vent line.
          To do that you will twist the 1/4 inch fuel line into a tight 3" circle and zip tie it to the top of the tank, then let the rest of the line fall down to the bottom of the tank where you will zip tie it again. Most guys will put a old fuel filter on the end of that new breather line to keep the dust out.
 
            Now on all carbs I really suggest that you use the throttle cable to adjust your idle. Adjust the cable on top of the carb up as far as possible. Then finish that adjustment on the steering wheel that way as the seasons change you can easily change the idle.

W8kski

  • Newbie
  • *
  • Posts: 12
  • Karma: 0
    • View Profile
New FL350 owner needs help
« Reply #2 on: March 08, 2010, 04:26:55 PM »
Sounds like I will be busy for a little while.  I'm going to add an electric fuel pump with the spun aluminum tank, but I'm guessing that I still need to add the vented return line at the neck of the tank?