1972 Float Adjustment ...

[siteunseen]

48 minutes ago, Patcon said:

Like I said before, you need a new mechanic! The needles in the carbs are the same front and rear! The 2.5 turns down is really sort of arbitrary. I would prefer both carbs were similar. IE both at 2.5 or 3.0 or 3.5 but it really won't be the end of the world if they're not 2.5 down. What matters is that the fuel level in each jet tube is the same. That is why Mark wants you to pull the domes off and visually inspect the fuel level in each jet!

Does it make sense that raising the float pin height on the front's ears to the same as the rear's would be the reason the front nozzle is lower at four turns down?

Just curious,  trying to learn/make sense of this on going problem.

The funny thing to me is @240260280 was down there right when all this mess started.

[Mark Maras]

 A clarification is in order. If the fuel level at the top of the nozzles is too high or too low, a readjustment of the float tang is the next step.  The goal is to see the fuel level 1/16" or less below the nozzle tops, mixture screws 2 1/2 turns down. One is actually adjusting the fuel level to the 2 1/2 turn down nozzle height. When that's correct one fine tunes the mixture screws to obtain the proper spark plug color.. (Old school)

 Jalex, You should take a good look at both needles when you remove the pistons. They should be the same. Hopefully they're visibly ID marked at the base. Compare the lengths too. Frequently, different needles have different lengths. Also. are your new needles and seats the same size or is one longer than the other.  Another also, Do you know if the needles and seats that are in the carbs now are different sizes? One more thing, after installing the domes, do the drop test to insure the needles aren't sticking in the nozzles.

 Got to go back and re-read this thread to see where we're at.

[jalexquijano]

1 hour ago, Mark Maras said:

 A clarification is in order. If the fuel level at the top of the nozzles is too high or too low, a readjustment of the float tang is the next step.  The goal is to see the fuel level 1/16" or less below the nozzle tops, mixture screws 2 1/2 turns down. One is actually adjusting the fuel level to the 2 1/2 turn down nozzle height. When that's correct one fine tunes the mixture screws to obtain the proper spark plug color.. (Old school)

 Jalex, You should take a good look at both needles when you remove the pistons. They should be the same. Hopefully they're visibly ID marked at the base. Compare the lengths too. Frequently, different needles have different lengths. Also. are your new needles and seats the same size or is one longer than the other.  Another also, Do you know if the needles and seats that are in the carbs now are different sizes? One more thing, after installing the domes, do the drop test to insure the needles aren't sticking in the nozzles.

 Got to go back and re-read this thread to see where we're at.

SM NEEDLES installed ztherapy and they are the same. Same level of fuel at 2.5 turns at the bridge. Shall we move forward with the floats and install the correct size of needle valve in the front and move to the higher ears in the lid?

[jalexquijano]

On 13/2/2018 at 5:10 PM, siteunseen said:

No, no.  The pin or needle on the valve rides on the hump of the metal bracket on the float. The lower the float the longer the pin the more fuel flows in. When the bowl is full of fuel it "floats" the float pushing the pin in; shorter.  Shuts the valve, no fuel enters.

If I had time and patience I could photograph the workings of the float with the needle valve BUT YOU HAVE A DVD THAT EXPLAINS IT ALL.  Please watch it, in slow motion if need be.

I watched it 3 times before I ever turned a screw to rebuild mine. It's all right in front of you, you've got tunnel vision. Nothing you buy will make this simple, it's a tedious task that takes time. You have to get the baseline measurement first, either the clear tube (cheaper) or the sight glasses (not so cheap).

Think this through, write down a plan and stick to it. You are bouncing all over this simple but very important task. Focus on the plan.

To fix a running toilet you simply bend the rod going to the float. Same thing with your carbs. 

Watch the DVD please. I'm getting bored repeating myself. If I want to do that I'll get a girl over here. At least I eat good and get a cold sore.

I got this reply from the aussie forum regarding the way the .55 inch gap measurement is taken. It seems to be contrary to your advice. 

[Mark Maras]

 Jalex, I can see that both nozzles are equal distance down. I can't see how far down the fuel is in relation to the top of the nozzle. Is the fuel within 1/16" of the nozzle tops? In the "open another can of worms" paragraph above, he's describing the same thing we're doing here. The setting he didn't know was the 2 1/2 turns down on a 3 and 4 screw.

[jalexquijano]

13 hours ago, Mark Maras said:

 Jalex, I can see that both nozzles are equal distance down. I can't see how far down the fuel is in relation to the top of the nozzle. Is the fuel within 1/16" of the nozzle tops? In the "open another can of worms" paragraph above, he's describing the same thing we're doing here. The setting he didn't know was the 2 1/2 turns down on a 3 and 4 screw.

Please clarify how the 0.55 or 9/16 gap is taken. Pursuant to the australian forum it is taken with the needle valve pin depressed supporting the weight. If this is not clear i cant move forward.

[siteunseen]

14 hours ago, jalexquijano said:

I got this reply from the aussie forum regarding the way the .55 inch gap measurement is taken. It seems to be contrary to your advice. 

They are located in the Southern Hemisphere, I'm in the Northern Hemisphere.  Everything is opposite. 

Toodle-oo mate.

con·trar·y

adjective

 

ˈkäntrerē/

1. 1.

   opposite in nature, direction, or meaning.

[jalexquijano]

Bottom line, which is the correct and precise way?  Just contacting the valve stem or with the float's weight falling down? Still not clear.

Edited February 18, 2018 by jalexquijano

[Mark Maras]

The second method is one way to double check the accuracy of the 9/16" setting which, as you've discovered, is a very grey area. The other two common ways to double check the float setting (9/16" grey area) are the sight glass and the clear tube. Both screw into the drain plug hole.

 Now that you've gotten the floats in that grey area they call 9/16", install the newly adjusted floats, start it up, run it for a minute or two, shut it down and pull the domes and pistons. This is the 100% method mentioned above. With the mixture screws 2 1/2 turns down, the fuel in the nozzles should be within 1/16" of the nozzle tops. If the fuel level is either too high or too low, a minor float tang adjustment will be needed. If you find the fuel levels are within the 1/16" of the nozzle tops and you GOT IT on the first try, a celebration is called for and maybe a lottery ticket while your luck is still holding.

 It wasn't until yesterday that I realized you were working on a spare set of floats. I'm assuming they have the different length pivot ears, are your needles and seats different lengths too?

 

[882993md]

Hi JALEX:

Here is a simple way that I set the .55" on my float tabs. Make or find something that is .55" that will sit on top of the float. You can use a wooden dowel rod that you cut down and sand it to exactly .55". I happen to have a sanding drum attachment for my Dremel moto-tool that just happens to measure .55".

1. Place your .55" object on top of the float

2. Raise up the float until the .55" object contact the underside of the cover. You are now exactly at .55"

3. Blow on the fuel inlet pipe.

4. If your breath circulates then the float tang is not pushing the pin and you have to adjust it up to push the pin. (i.e. stop fuel flow at .55")

5. If your breath stops and you can't blow that is good. HOWEVER you must ensure float tang is not bent too far up (i.e. pushing the pin to far in at .55"). You want your breath (fuel) to stop at exactly .55".

6. All of this is performed with the float right side up-exactly like it would be when installed on your carb. Forget the upside down stuff.

7. You also need to fix your float tab angle first. I haven't adjusted my rear carb. float tab yet and it is like a ramp. It should be like a speed bump 

Quote

Bend that back part by the pin holes that's so high, like a ramp, down even with the front part.  Needle nose on the sides of the ramp and roll your hand back towards the pin holes.  Don't bend it, more of a roll so the pin will ride smoothly.  It should look like a speed bump not a ramp. @siteunseen

 

 

 

 

 

 

Edited February 18, 2018 by 882993md

[882993md]

[jalexquijano]

12 minutes ago, 882993md said:

Hi JALEX:

Here is a simple way that I set the .55" on my float tabs. Make or find something that is .55" that will sit on top of the float. You can use a wooden dowel rod that you cut down and sand it to exactly .55". I happen to have a sanding drum attachment for my Dremel moto-tool that just happens to measure .55".

1. Place your .55" object on top of the float

2. Raise up the float until the .55" object contact the underside of the cover. You are now exactly at .55"

3. Blow on the fuel inlet pipe.

4. If your breath circulates then the float tang is not pushing the pin and you have to adjust it up to push the pin. (i.e. stop fuel flow at .55")

5. If your breath stops and you can't blow that is good. HOWEVER you must ensure float tang is not bent too far up (i.e. pushing the pin to far in at .55"). You want your breath (fuel) to stop at exactly .55".

6. All of this is performed with the float right side up-exactly like it would be when installed on your carb. Forget the upside down stuff.

7. You also need to fix your float tab angle first. I haven't adjusted my rear carb. float tab yet and they are like ramps. They should be like speed bumps @siteunseen

 

 

 

 

 

 

Your explanation is as clear as water. Best in all. Ill use a 9/16 drill bit.