Speed Demon Carb Float Question
Thread Starter
"Rodstoration &am p;quot; In Progres
Joined: Jun 2004
Posts: 1,397
Likes: 1
From: Frisco TX
Speed Demon Carb Float Question
Recently, we've had an issue with our primary fuel bowl overfilling and fuel dripping into the carb/manifold...ultimately resulting in a significantly flooded engine. Looked at the fuel sight plug and could see that the bowl was over filling.
Took the fuel bowl off and worked the float up and down...didn't seem to be binding in any way. Re-assembled and is now working.
I don't know much about this mechanism and would appreciate any advice the experts here may have on what I should look for.
It is important that I fix this one as when the flooding occurs...we're stranded...sometimes the engine will not even turnover requiring us to pull spark plug(s) to get the flooded cylinder(s) drained...
Thanks in advance everyone... Ed
Took the fuel bowl off and worked the float up and down...didn't seem to be binding in any way. Re-assembled and is now working.
I don't know much about this mechanism and would appreciate any advice the experts here may have on what I should look for.
It is important that I fix this one as when the flooding occurs...we're stranded...sometimes the engine will not even turnover requiring us to pull spark plug(s) to get the flooded cylinder(s) drained...
Thanks in advance everyone... Ed
Race Director
Joined: Sep 2004
Posts: 11,874
Likes: 263
From: Arlington Va Current ride 04 vert, previous vettes: 69 vert, 77 resto mod
what kind of fuel filter are you using and is this the first time it happened? sometimes there is debris from the manufacturing process that gets stuck as it works its way out
Melting Slicks
Joined: May 2003
Posts: 2,387
Likes: 2
From: Meriden CT
I had a problem on my Speed Demon where I turned the adjustment screw a hair too much... the threads disengaged, and the float dropped. The bowl then completely filled, and was dumping fuel into the engine.
I even let the car run for a while after I made the adjustment, but still left me on the side of the road. Kind of embarrasing when you have to get towed a half mile back home.
I even let the car run for a while after I made the adjustment, but still left me on the side of the road. Kind of embarrasing when you have to get towed a half mile back home.
Tech Contributor
Joined: Aug 1999
Posts: 14,356
Likes: 6,332
From: At my Bar drinking and wrenching in Lafayette Colorado
We've seen problems on Speed Demons with porous float bowl castings. With the float raised and the needle/seat closed, fuel will continue to pour into the bowl right through the pores in the casting in the area of the seat. You can pull the bowl off, flip it inverted so the float/nedle seats and closes, and then apply 5 psi of air pressure to the fuel line inlet. Use some soapy water solution as a bubble leak check medium. You will immediately see the leak area and the problem.
Race Director
Joined: Nov 2000
Posts: 11,872
Likes: 12
From: Waterloo ontario Canada
If I have a leaking needle and seat I just unscrew the needle and seat, blow them out with my mouth or air and reinstall. That usually fixes the problem. No need to remove the float bowl. 5/8th wrench and screw driver
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Thread Starter
"Rodstoration &am p;quot; In Progres
Joined: Jun 2004
Posts: 1,397
Likes: 1
From: Frisco TX
Pulled the bowl and found small pieces of black ??? in there....one was even stuck in one of the jets. Pulled the secondary bowl and found a smaller amount but the same stuff... Had to have come in via the fuel line and I'll bet one of them got stuck in the needle valve keeping it from closing. Had to have come from the new russell filter I installed a few weekends ago.
My bad...as I rushed the installation and didn't flush the new filter out with a fresh flow of fuel before hooking it to the carb. So, saving 5 min cost me several hours of being broken down, embarrasment and having to confess here.
Regardless, I learned a lot from all of the comments above! So if my carb ever gives me a hard time again I now know a lot about the carb bowls and potential problems with the float, valve and leaks.
Thanks again everyone and sorry about the stupid move....lesson learned. Ed
My bad...as I rushed the installation and didn't flush the new filter out with a fresh flow of fuel before hooking it to the carb. So, saving 5 min cost me several hours of being broken down, embarrasment and having to confess here.
Regardless, I learned a lot from all of the comments above! So if my carb ever gives me a hard time again I now know a lot about the carb bowls and potential problems with the float, valve and leaks.
Thanks again everyone and sorry about the stupid move....lesson learned. Ed
Last edited by 80TexasC3; Feb 18, 2007 at 09:42 AM.
Melting Slicks
Joined: Dec 2004
Posts: 2,161
Likes: 0
From: pr, frederick md.
i recently had this happen to me, and i adjusted the floats to lower the level, and its been kinda ok. the adjustment wasnt loose so how can it be ok now at such a lower setting? we just had a pres. day sale at local speed shop and i got the rebuild kit. man this BG carb has been a pain in my azz!
