holley fuel level help
Thread Starter
Drifting
Joined: Mar 2011
Posts: 1,271
Likes: 1
From: PA
holley fuel level help
i know holleys. i have never had this problem though. the carb is an ebay carb so i could be looking at a bubba mistake somewhere....
i cant seem to adjust my secondary bowl fuel level lower. i have put in new needles/seats. cleaned several times. triple checked float level. but i still get the fuel maxing out at the top of the bowl. i dont have seepage from the boosters (as far as i can see) but no matter what i do it goes back to too high.
its a holley 670 SA carb.
wrong gaskets ? what gives ?
i cant seem to adjust my secondary bowl fuel level lower. i have put in new needles/seats. cleaned several times. triple checked float level. but i still get the fuel maxing out at the top of the bowl. i dont have seepage from the boosters (as far as i can see) but no matter what i do it goes back to too high.
its a holley 670 SA carb.
wrong gaskets ? what gives ?
Instructor
Joined: Sep 2007
Posts: 198
Likes: 0
From: Colorado Springs Colorado
boltnut, I don't know if this is the same problem I had along time ago, but it sounds similar. My fuel level was too high, so I screwed the adjuster down. the level didn't drop right away, so I screwed it down some more. (I wasn't thinking that the secondary level wouldn't drop right away like the primary side does). Anyway, I screwed it down so far it bent the float tang down, which let fuel keep running through the needle/seat. I removed the bowl, bent the tang back to level, and adjusted it a couple of times after test drives (to open the secondary's). Hope this makes sense.
Drifting
Joined: Jan 2002
Posts: 1,645
Likes: 11
From: Schaumburg IL
Pull the bowl and clean the secondary plate and jets with carb cleaner. Hold the bowl and see if the float, needle and seat move freely and where the dry float level is. for a starter you can set the float level in the middle of the bowl and that will be real close.
Instructor
Joined: Sep 2007
Posts: 198
Likes: 0
From: Colorado Springs Colorado
I'm sure you know this already, but the accelerator pump's passages need to be clear for the fuel to flow. I'd take the secondary accelerator pump off, and the squirter, and blow some carb cleaner through the passage. Also make sure the squirter isn't clogged, or diaphram's not damaged.
Melting Slicks
Joined: May 2002
Posts: 2,716
Likes: 121
From: Sulphur LA
St. Jude Donor '05-'06,'11,'13-'14,'16,'18,'19,'24, '25
If its got a hollow float than check to see if the float has fuel in it.
It wont take much fuel to submerge the float enough to cause the issues you are seeing.
With a vacuum secondary carb you wont be able to make the secondaries flow fuel with no load on the engine.
Neal
It wont take much fuel to submerge the float enough to cause the issues you are seeing.
With a vacuum secondary carb you wont be able to make the secondaries flow fuel with no load on the engine.
Neal
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Le Mans Master
Joined: Mar 2008
Posts: 5,948
Likes: 72
From: Oxford MA-----You just lost the game!!!!
You don't really sound like a guy who "knows Holleys". If I were you, I would get my hands on a rebuild kit, and rebuild the carb. You never know, a complete lunatic could have owned that carb before you.
Scott
Scott
Thread Starter
Drifting
Joined: Mar 2011
Posts: 1,271
Likes: 1
From: PA
Neither do you so maybe you shoudnt reply. This is the first vac secondary SA carb I've owned. It was bought off eBay and I may have a bubba issue. I'm trying to trouble shoot blind. For all I know it has the wrong main body gasket on there. The SA carbs had issues when first introduced and this is one of them. Some of the 4150 4160 gaskets are interchangeable so I can't be sure if what is on there is correct without something to check against. I'll pull out my Holley books and do some research if no one has run into this and found the issue.
What I am getting is perplexing. There is no blockage. All parts are new.( or appear so) yet my fuel level only rises never lowers. No matter what I try. Full throttle blasts, new seats, float level reset. You name it.
What I am getting is perplexing. There is no blockage. All parts are new.( or appear so) yet my fuel level only rises never lowers. No matter what I try. Full throttle blasts, new seats, float level reset. You name it.
Burning Brakes
Joined: May 2009
Posts: 1,232
Likes: 6
From: Tucson AZ
St. Jude Donor '12
I'm no Holley expert here by any means (although I dated a Holly once), but couldn't you remove the sight screw and let the excess flow out (into something else) until as you adjust, the spillover stops?
Thread Starter
Drifting
Joined: Mar 2011
Posts: 1,271
Likes: 1
From: PA
Actually what I do is use a LARGE syringe to pull fuel out and lower the level. After I run the car the level goes back up and will not go down . I am not sure if the seconds are not opening or if they are and the fuel isn't flowing.
Melting Slicks
Joined: May 2002
Posts: 2,716
Likes: 121
From: Sulphur LA
St. Jude Donor '05-'06,'11,'13-'14,'16,'18,'19,'24, '25
Thread Starter
Drifting
Joined: Mar 2011
Posts: 1,271
Likes: 1
From: PA
I thought I might get a little squirt, a puff, anything by manually working the seconds.....nothing at all.
Maybe a bad diaphragm...?
Thread Starter
Drifting
Joined: Mar 2011
Posts: 1,271
Likes: 1
From: PA
That would point to the throttle blades not opening.....I had the light yellow spring in the housing last run. Should have started opening early....