I've been messing with the lock nut on the fuel bowls of my holley 600, started out ok, but continously had troubles getting the fuel to get low enough...

by the time it was looking like i had things almost in order i had ruined whatever this black telfon looking stuff (pic) surrounding the screw and nut, therefor i ended up with leaks on both lock nuts.

i went to NAPA and got a holley fuel bowl gasket set, which is all one sized gasket for the screw. put that in and then i was still getting leaks, this time from around the bottom of the nut where it compresses to the carb. then i tried some o-rings which quickly turned to destroyed plastic after tightening it down.

my conclusion is whatever this black teflton looking stuff that was on there in the first place is all thats going to work, does anyone know what it is?

i need to get some and fix up these leaks ASAP!

thanks!

 

That's just a fiber washer that goes under the nut. It's similar to the one that goes under the screw head. Get yourself some new ones and coat them with Chapstick so you don't tear them up while making the float level adjustment. Make sure there isn't a burr on the float bowl tearing the washer. Is it safe to assume you know the float level adjustment procedure?

 

O-Rings, but dont tighten them down as tight? The rubber is what makes the seal, not the brute pressure. Otherwise, it sounds like Josh knows his stuff

~T.J.

 

i'll check NAPA and see if they have any washers that'll fit, if not i guess i'll try home depot or something.

i'm somewhat familiar with adjusting the float bowls, basically just line up the fuel level to the bottom of the sight glass within 1/16 or so. trouble i was having is when i tightened the lock-nut down enough to keep fuel from spilling out, i would also have to tighten down the screw which essentially messed up whatever adjustments i had made.

reason i was trying to adjust these in the first place is the car is massively backfiring pretty much every time i go over 5000rpm and then switch gears.

 

i went and checked at NAPA and the guy pulled out a old Holley 600 he had laying around to see what was used for sure, and its just a couple of washers, he gave me the bolts for free so i figured id be on my way. tried that on the car and it was still leaking.

i'm not really sure whats going on here, the float seems to keep messing up on the secondary no matter how the float screws are set and the secondarys dont seem to be even coming on. i have the secondaries setup mechanically and giving it full throttle at idle shows no gas coming out of the jets... so hmmmm.. something is wrong.

any ideas?

 

you're aware that the nut is used to set float height and the screw is the "locknut" right?

 

Sounds like your float may be out of adjustment so far that no matter how much turning of the adjuster you do, it will not adjust the level. I would suggest taking the bowl assembly off of the carb and, at least, visually adjust the float level, the use the adjuster screw for finer adjustments.

 

Yeah i am, which was giving me confusion since if the nut is tightened to the right it should lean out the bowl. however with it tightened down almost as far as it'll go its still full of gas.

looks like there's something jamming up inside. bah...

anyone know any good websites to teach the basics on this? i have the haynes rebuild manual but it really doesnt cover a lot of the basics of tuning and adjustment.

thanks guys

 

Make sure your fuel pressure is not over 7psi, and that your needle and seat assembly is not too short. They *do* make them in different lengths...

Also make sure your float hasn't become "heavy".