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1972 Float Adjustment ...


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 Clean the pistons and get back to the floats. You'll find out later if the staining was caused by poor tuning. 

5 hours ago, jalexquijano said:

I would like to tune the floats myself. In trying to make him understand the both carbs must be at 2.5 turns clockwise and he said it is not possible as the car will run rich.

 So he's telling you that unless he unscrews the mix. screws to somewhere down near 4 turns (on one carb only) it runs too rich? Someone has something backward. The farther the mix. screws are unscrewed (dropped), the richer it will run. Based on the info from your mechanic, you already know more about your carbs than your mechanic and have the desire to tune the floats yourself. The only thing that's stopping you, is you. Go for it. WE CAN DO IT.

Edited by Mark Maras
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When you say clockwise I guess you mean clockwise when you look down at it. But the mix nut is underneath the carb. It's like any normal fastener. When you screw it clockwise it tightens (moves the nozzle up), counterclockwise it loosens (moves the nozzle down). So 2 1/2 turns  counterclockwise is 2 1/2 turns down. You need to get the terminology right because if you follow the tune-up procedure in the FSM (which is the best method in my opinion, and the easiest to follow if you're not an expert since it's written out correctly step-by-step), that's the terminology they use. Think of it as if you're looking at the carb from underneath.

I agree 100% with the previous post, BTW.

 

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Okay. If i want to verify that both carbs are synchonized at the same 2.5 turns clockwise which means lowering the nozzle at 2 full turns and a half isnt these pictures sufficient proof? I  still dont understand why my mechanic lowered the jet  to 4 turns and drilled another hole to compensate the height of the needle valve. The guys at ztherapy supposedly set both jets at 2.5 turns equally.

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20180217_172214.jpg

Edited by jalexquijano
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 I'm sure he had a good reason at the time, although I can't explain why. But, if I had to hazard a guess, he may have been trying to compensate for a float setting that left the fuel too low in the nozzle. Let's proceed. Your goal now is to get the fuel level within 1/16" of the top of the hole in the center of the nozzle. (Leave the nozzles at 2 1/2 turns) To achieve the 1 1/6" fuel level,  you'll be adjusting (re-bending) the float tangs either up or down. At this point you don't care about the 9/16" float measurement. Ignore it. Don't even go there. After each adjustment, reassemble the carbs, fire it up, run it for a minute, shut it down and pull the domes and pistons. Look again to see the new fuel level. Readjust the floats until the fuel levels are correct. Then we'll go into fine tuning with the mixture screws. Piece of cake.

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11 minutes ago, Mark Maras said:

 I'm sure he had a good reason at the time, although I can't explain why. But, if I had to hazard a guess, he may have been trying to compensate for a float setting that left the fuel too low in the nozzle. Let's proceed. Your goal now is to get the fuel level within 1/16" of the top of the hole in the center of the nozzle. (Leave the nozzles at 2 1/2 turns) To achieve the 1 1/6" fuel level,  you'll be adjusting (re-bending) the float tangs either up or down. At this point you don't care about the 9/16" float measurement. Ignore it. Don't even go there. After each adjustment, reassemble the carbs, fire it up, run it for a minute, shut it down and pull the domes and pistons. Look again to see the new fuel level. Readjust the floats until the fuel levels are correct. Then we'll go into fine tuning with the mixture screws. Piece of cake.

I installed the taller size needle and seat and move the pin of the float to the original slot.

20180220_192326.jpg

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 Sounds good. Give it a crude (grey area) 9/16" adjustment and reassemble the carbs. Start it up, run it for a minute, shut it down and check the fuel height in the nozzles. Readjust the float tangs to get the fuel level to within 1/16" of the nozzle tops which are still 2 1/2 turns down. This may take a few tries (along with float gaskets) to get them right. Keep us posted on your progress.

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1 hour ago, Mark Maras said:

 I'm sure he had a good reason at the time, although I can't explain why. But, if I had to hazard a guess, he may have been trying to compensate for a float setting that left the fuel too low in the nozzle. Let's proceed. Your goal now is to get the fuel level within 1/16" of the top of the hole in the center of the nozzle. (Leave the nozzles at 2 1/2 turns) To achieve the 1 1/6" fuel level,  you'll be adjusting (re-bending) the float tangs either up or down. At this point you don't care about the 9/16" float measurement. Ignore it. Don't even go there. After each adjustment, reassemble the carbs, fire it up, run it for a minute, shut it down and pull the domes and pistons. Look again to see the new fuel level. Readjust the floats until the fuel levels are correct. Then we'll go into fine tuning with the mixture screws. Piece of cake.

How to i measure the 1/16 over the top of the nozzle?

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8 minutes ago, jalexquijano said:

Can i try with the pair of clear sight plastic tubes i bought from z therapy and which are fastened on the drain plugs? Will i be able to get the floats set better with these tubes more precisely? If so how does this work?

 Sure, you can use the tube method and it will get you there or close to it. Probably "good enough". The method that I'm suggesting is the 100% sure way to know that the fuel is at the proper height. Keep in mind that the float adjustment is THE PRIMARY MIXTURE SETTING. Get that right and everything else gets a lot easier.

 

13 minutes ago, jalexquijano said:

How to i measure the 1/16 over the top of the nozzle?

 Not over the nozzle. The fuel level should be even with or just below the top of the small hole in the center of the nozzle. This is the hole that the needle slides into. The fuel level can be below the nozzle top as much as 1/16" but should never be over the top of the nozzle. Fuel over the nozzle top will result in fuel puddling above the nozzle. No need to measure the 1/16". Just eyeball the fuel level so it's as close to the nozzle top as you can get it without going over. Luck.

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On 20/2/2018 at 11:43 PM, Mark Maras said:

 Sure, you can use the tube method and it will get you there or close to it. Probably "good enough". The method that I'm suggesting is the 100% sure way to know that the fuel is at the proper height. Keep in mind that the float adjustment is THE PRIMARY MIXTURE SETTING. Get that right and everything else gets a lot easier.

 

 Not over the nozzle. The fuel level should be even with or just below the top of the small hole in the center of the nozzle. This is the hole that the needle slides into. The fuel level can be below the nozzle top as much as 1/16" but should never be over the top of the nozzle. Fuel over the nozzle top will result in fuel puddling above the nozzle. No need to measure the 1/16". Just eyeball the fuel level so it's as close to the nozzle top as you can get it without going over. Luck.

I also did the sight tube test on the front and rear carb but it does not reach to the correct level in the rear and front carb.

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