Float level valve problemes (Demon)
Thread Starter
Pro
Joined: May 2011
Posts: 722
Likes: 58
From: Karlsruhe (Germany)
Float level valve problemes (Demon)
Hi,
today it happend the third time i had a stuck float level on my demon six shooter (Tripower Carb). Then the fuel flows all over the carb outside.
I stopped the fuel pump, let it run until the bowl was empty, then ran the pump and the problem was solved.
Is this a common problem with Holley or Demon valves?
I had it disassembled when it happend the first time. But it looked perfekt and was clean. Reassembled and it was ok for 5000 miles until today.
What to do? I know it will look good again. Should i just repalce it? Or are there better types to buy?
today it happend the third time i had a stuck float level on my demon six shooter (Tripower Carb). Then the fuel flows all over the carb outside.
I stopped the fuel pump, let it run until the bowl was empty, then ran the pump and the problem was solved.
Is this a common problem with Holley or Demon valves?
I had it disassembled when it happend the first time. But it looked perfekt and was clean. Reassembled and it was ok for 5000 miles until today.
What to do? I know it will look good again. Should i just repalce it? Or are there better types to buy?
Thread Starter
Pro
Joined: May 2011
Posts: 722
Likes: 58
From: Karlsruhe (Germany)
4-5 psi.
Saw at Summit, that there are viton and steel needle and seat assemblies available.
Steel is for alcohole fuels, and they are expensiver. But maybe they last also longer or are more relaiable?
The normal needles have a viton rubber cone.
Saw at Summit, that there are viton and steel needle and seat assemblies available.
Steel is for alcohole fuels, and they are expensiver. But maybe they last also longer or are more relaiable?
The normal needles have a viton rubber cone.
Team Owner
Joined: May 2001
Posts: 87,302
Likes: 1,583
From: Western NY
Hi,
today it happend the third time i had a stuck float level on my demon six shooter (Tripower Carb). Then the fuel flows all over the carb outside.
I stopped the fuel pump, let it run until the bowl was empty, then ran the pump and the problem was solved.
Is this a common problem with Holley or Demon valves?
I had it disassembled when it happend the first time. But it looked perfekt and was clean. Reassembled and it was ok for 5000 miles until today.
What to do? I know it will look good again. Should i just repalce it? Or are there better types to buy?
today it happend the third time i had a stuck float level on my demon six shooter (Tripower Carb). Then the fuel flows all over the carb outside.
I stopped the fuel pump, let it run until the bowl was empty, then ran the pump and the problem was solved.
Is this a common problem with Holley or Demon valves?
I had it disassembled when it happend the first time. But it looked perfekt and was clean. Reassembled and it was ok for 5000 miles until today.
What to do? I know it will look good again. Should i just repalce it? Or are there better types to buy?
Drifting
Joined: Dec 2002
Posts: 1,946
Likes: 28
From: Long Beach CA
From your description, it sounds like there is crud getting into the needle valve/seat. The valve can't seal fully, and the pump keeps pushing gas in. When you shut off the pump and run the carb dry, the float drops, opening the valve more fully. The initial rush of fuel when the pump starts again, blows the crud out of the valve/seat, and it's working again. It doesn't take a very big piece of crud to mess things up. Are you using a good fuel filter? Is there stuff floating around in the gas tank?
Thread Starter
Pro
Joined: May 2011
Posts: 722
Likes: 58
From: Karlsruhe (Germany)
I have a standard fuel filter right befor the carb.
Ok, i have replaced a fitting of the line between filter and carb, maybe something happened there.
The last time when the problem occured i had a look inside the bowl but it was clean inside. That why i think crud is not the problem...
I have ordered now a rebuilt kit, including the needle and seat, hoping replacing it will help.
Ok, i have replaced a fitting of the line between filter and carb, maybe something happened there.
The last time when the problem occured i had a look inside the bowl but it was clean inside. That why i think crud is not the problem...
I have ordered now a rebuilt kit, including the needle and seat, hoping replacing it will help.
Team Owner
Joined: May 2001
Posts: 87,302
Likes: 1,583
From: Western NY
From your description, it sounds like there is crud getting into the needle valve/seat. The valve can't seal fully, and the pump keeps pushing gas in. When you shut off the pump and run the carb dry, the float drops, opening the valve more fully. The initial rush of fuel when the pump starts again, blows the crud out of the valve/seat, and it's working again. It doesn't take a very big piece of crud to mess things up. Are you using a good fuel filter? Is there stuff floating around in the gas tank?
I had a similar problem occur with a Holley 4 BBL. a number of years ago.
To the OP, why do you feel the need for an electric fuel pump? The mechanical pump is more than capable of feeding 90% of the engines in the field, and in many cases, where carbs are in use, safer.
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Le Mans Master
Joined: Oct 2010
Posts: 6,922
Likes: 839
From: melbourne florida
2023 C3 of the Year Finalist - Modified
i agree, Teflon tape is a serious no no. i. see guys today using it on natural gas which is a bigger no no and violates every code book written. it has caused houses and cars to burn. please do not use it on fuel!!!
Race Director
Joined: Jan 2000
Posts: 12,399
Likes: 247
From: San Jose CA
I used to be quite guilty of this... takes a while to learn to trust a compression fitting, I guess... not to mention, realize that the teflon tape does ABSOLUTELY NOTHING! 
I've seen "experienced" mechanics use it on compression fittings.
I've seen "experienced" mechanics use it on compression fittings.
Burning Brakes
Joined: Jan 2006
Posts: 1,088
Likes: 181
From: NC
2022 C2 of the Year Finalist - Modified
Hi,
today it happend the third time i had a stuck float level on my demon six shooter (Tripower Carb). Then the fuel flows all over the carb outside.
I stopped the fuel pump, let it run until the bowl was empty, then ran the pump and the problem was solved.
Is this a common problem with Holley or Demon valves?
I had it disassembled when it happend the first time. But it looked perfekt and was clean. Reassembled and it was ok for 5000 miles until today.
What to do? I know it will look good again. Should i just repalce it? Or are there better types to buy?
today it happend the third time i had a stuck float level on my demon six shooter (Tripower Carb). Then the fuel flows all over the carb outside.
I stopped the fuel pump, let it run until the bowl was empty, then ran the pump and the problem was solved.
Is this a common problem with Holley or Demon valves?
I had it disassembled when it happend the first time. But it looked perfekt and was clean. Reassembled and it was ok for 5000 miles until today.
What to do? I know it will look good again. Should i just repalce it? Or are there better types to buy?
You're one of the few, like me, who have the SixShooter setups actually running on the street. Alot of folks bought and installed them, then gave up when they had continuing flooding problems.
I live in Charlotte,NC, and Barry Grant's pro stock shop was about 30 minutes away. I had the same flooding issues, and bought new bowls and needle and seats from BG, but it didn't solve the problem. So I "happened by" the pro stock shop and the techs there bent over backward to help me.
What the problem was: the bowls had a porosity problem when they were cast. The techs cut another groove in the needle and seat below the original one. This placed the o'ring down in an area that had no porosity and fuel couldn't get bye when the needle/seat was closed.
This may not be your problem, but you may want to check it out.
BILL
Racer
Joined: Apr 2006
Posts: 477
Likes: 43
From: Millbrae California
The float that BG used in these carburetors was a nytrophl float with a very flexable float arm, we had very good luck replacing it with a brass float (standard hygrade # FL90). The brass float has a stronger arm plus you can bend the part of the arm that contacts the needle and seat if the o-ring on the N&S is in a area of the bowl that is not machined properly.
I hope this helps Henry @ oles carb
I hope this helps Henry @ oles carb
Racer
Joined: Apr 2006
Posts: 477
Likes: 43
From: Millbrae California
The float that BG used in these carburetors was a nytrophl float with a very flexable float arm, we had very good luck replacing it with a brass float (standard hygrade # FL90). The brass float has a stronger arm plus you can bend the part of the arm that contacts the needle and seat if the o-ring on the N&S is in a area of the bowl that is not machined properly.
I hope this helps Henry @ oles carb
I hope this helps Henry @ oles carb
Thread Starter
Pro
Joined: May 2011
Posts: 722
Likes: 58
From: Karlsruhe (Germany)
Hi,
the reason i am using an electric fuel pump is, because my engine block does not support mechanical pumps.
Found an older pic on my website, showing the inside of the bowl:
I pulled the center carb today, opened the bowl and found a very little piece of rubber inside. Maybe this was the reason and it stuck between needle and seat. Must be a piece from the fuel line.
After that i wanted to rise the level a bit in the rear carb, because it was always a bit low. So turned the nut 1/4 turn and started the pump to see if everything was tight.
Then the rear carb was floated! This sucks. Well i turned again a little at the nut and tried it again, then it stopped floating.
the reason i am using an electric fuel pump is, because my engine block does not support mechanical pumps.
Found an older pic on my website, showing the inside of the bowl:
I pulled the center carb today, opened the bowl and found a very little piece of rubber inside. Maybe this was the reason and it stuck between needle and seat. Must be a piece from the fuel line.
After that i wanted to rise the level a bit in the rear carb, because it was always a bit low. So turned the nut 1/4 turn and started the pump to see if everything was tight.
Then the rear carb was floated! This sucks. Well i turned again a little at the nut and tried it again, then it stopped floating.