Holley instructions contradicting on fuel bowl level ??

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bend the tang on the float. IIRC adjust float 'hang' when you turn the bowl over: put a pencil between the inverted float and the top of the bowl (bottom when its inverted) and adjust so the pencil is the feeler guage. They do it here to some extent. Yellow line is bottom of plug, midpoint on large sight glass (way safer than dribbling plugs on an idling motor!)
float.jpg


Also on an older Holley, you are turning the large floating nut under the screw top that is keyed onto the needle seat, your not turning the needle seat directly. The top large head screw is the gasket sealing mechanism. loosen screw slightly, turn nut and tighten screw: a big mess when your motor is running as your surely going to get fuel at 5-7 psi to squirt out of screw.
 
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Mattax said:
Just to clarify
Its not a matter of whether the sight plug is clear or not. There are clear plugs that screw into the site plug location.
Its a matter of placement. The middle of the large windows is about the same as the bottom of the threaded plugs.
The window types do not screw in. Look at the position in the carbs I posted.

As far as the adjustments having run out. Take it off and see what's going on.
I agree with what was said by the others. Was just posting photos to clarify.
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The pictures were great ! thanks for showing everything clearly.
 
.110 is typical and would do a better job than the .150 of controlling fuel at closed throttle situations where the mechanical pump pressure is going to hit maximum.

You may also need a set of bowl gaskets and maybe block gaskets. Whether the ones on there can be reused depends on what's on there and condition. I'd assume not. Holley blue gaskets work fine. Kill the sticky on them with a touch of WD-40 or such. Makes disassembly easier. 10 packs are much better buy than the typical 2 packs if you're going to be tuning etc.
Interface gasket material is harder and a lot of carb guys prefer that. If you buy from BLP that's prob what you'll get.
 
The best, best by far, beating all comers is the Superformance gaskets. I refuse to use anything else. Ever. They never stick, you don't have to screw with them, and I've had bowls off over a dozen times and reused them and never had a leak.


Thanks for the tip on the nylon gaskets Mattx. I haven't had issues yet, but I'm going to keep a very close eye on them.
 
yellow rose said:
The best, best by far, beating all comers is the Superformance gaskets. I refuse to use anything else. Ever. They never stick, you don't have to screw with them, and I've had bowls off over a dozen times and reused them and never had a leak.


Thanks for the tip on the nylon gaskets Mattx. I haven't had issues yet, but I'm going to keep a very close eye on them.
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Sure. It caught me by surprise. Of course the trunk was full and my tool boxes stuffed up under the package shelf. Good thing there was a spot to park away from the gas station pumps. Took me a bit figured out why it loosened up, and then patience to wait for things to cool.
A couple posts and a photo here. Fuel leak at fuel bowls
 
Mattax said:
.110 is typical and would do a better job than the .150 of controlling fuel at closed throttle situations where the mechanical pump pressure is going to hit maximum.

You may also need a set of bowl gaskets and maybe block gaskets. Whether the ones on there can be reused depends on what's on there and condition. I'd assume not. Holley blue gaskets work fine. Kill the sticky on them with a touch of WD-40 or such. Makes disassembly easier. 10 packs are much better buy than the typical 2 packs if you're going to be tuning etc.
Interface gasket material is harder and a lot of carb guys prefer that. If you buy from BLP that's prob what you'll get.
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So interesting thing... I honestly only messed with the secondary bowl last night, but i replaced the N/S with the .110 suggested. But when I went to the primary instead of being .150 like the secondary it was .120 sized... So would it be wise to make both primary/secondary the same or is it okay to keep the primary .120 and leave the secondary .110?
 
Don't know if it's been mentioned yet, but, check where the needle bears on the float arm...many times this is bent down so no amount of screwing down the needle assembly will close the needle...

Untitled.jpg
 
DartThis74 said:
So interesting thing... I honestly only messed with the secondary bowl last night, but i replaced the N/S with the .110 suggested. But when I went to the primary instead of being .150 like the secondary it was .120 sized... So would it be wise to make both primary/secondary the same or is it okay to keep the primary .120 and leave the secondary .110?
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In most situations not much fuel is drawn from the bowls. That is at low throttle, such as idle, decelerating, and cruising on local roads.
More power is needed and therefore more fuel is needed at interstate speeds. Its still no where close to maximum.
Only in something like a 1/4 mile run, in the upper gears at WOT, is the engine consuming a lot of fuel which needs to be replaced.
If this car is being raced or run at the track, then depending on the hp, rpm, pump, fuel, etc, a larger inlet may be helpful.
The larger it is, the more easily it can be pushed open. Pressure in the supply line is maximum when the valves are shut (unless a regulator is used).
It could be 6 or 7 psi when the inlet valves are shut. Some of the new pumps are even higher - which pretty much guarentees overfilling the bowls.
Down the track, as long as it maintains 3 -4 psi, often all thats needed. Again, all depends on the details mentioned above.


1970 Carburetion Fundamentals and Facts Master Technician Service Conference Series Filmstrip (Session 273)

1970 Carburetion Fundamentals & Facts, p3 The Float
 
Mattax said:
In most situations not much fuel is drawn from the bowls. That is at low throttle, such as idle, decelerating, and cruising on local roads.
More power is needed and therefore more fuel is needed at interstate speeds. Its still no where close to maximum.
Only in something like a 1/4 mile run, in the upper gears at WOT, is the engine consuming a lot of fuel which needs to be replaced.
If this car is being raced or run at the track, then depending on the hp, rpm, pump, fuel, etc, a larger inlet may be helpful.
The larger it is, the more easily it can be pushed open. Pressure in the supply line is maximum when the valves are shut (unless a regulator is used).
It could be 6 or 7 psi when the inlet valves are shut. Some of the new pumps are even higher - which pretty much guarentees overfilling the bowls.
Down the track, as long as it maintains 3 -4 psi, often all thats needed. Again, all depends on the details mentioned above.


1970 Carburetion Fundamentals and Facts Master Technician Service Conference Series Filmstrip (Session 273)

1970 Carburetion Fundamentals & Facts, p3 The Float
Click to expand...

So good news, I got the car fired back up and all is good now. That .110 on the secondary really helped me get many more threads to catch on the adjuster nut and I was able to get the fuel up midway on the sight glass now no problem. I did see that on my fuel pressure gauge it's reading about 7.0-7.2 PSI. Holley's instructional video says 7 is high and 6 is normal, but when reading the setup guide for my 80802 carb from their website it said pressure should be between 5-7.5. So... Is being at or near 7 okay?

upload_2019-9-26_7-56-42.png
 
DartThis74 said:
So good news, I got the car fired back up and all is good now. That .110 on the secondary really helped me get many more threads to catch on the adjuster nut and I was able to get the fuel up midway on the sight glass now no problem. I did see that on my fuel pressure gauge it's reading about 7.0-7.2 PSI. Holley's instructional video says 7 is high and 6 is normal, but when reading the setup guide for my 80802 carb from their website it said pressure should be between 5-7.5. So... Is being at or near 7 okay?

View attachment 1715399192
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In my experience, that's pushing the limits. Definately put the smaller 110 needle in the primary bowl and/or get a pump with return spring that keeps pressure below 7 psi.
I hate to spend your money, but I think that's worth it. There's not a lot of options for fuel pumps on LA engines with the '70 up waterpump. I found good pressure control and volume delivery using Holley's 'Keith Dorton' 110 mechanical pump, but its over 10 years old. I'd like to think new ones still the same internally, but I don't know that for sure.

Nice thing about the clear sight plugs on your fuel bowls is that you can see if the level has risen or fallen since you set it.
If you do need to dump some fuel out of a bowl in an emergency, back off a bowl screw and drain it into a sardine can or whatever. I've even had to use a rag - hardly the best the choice but prob better than dumping on the engine.... :(
 
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Check the fuel pressure with a different gauge and compare the reading
 
Mattax said:
In my experience, that's pushing the limits. Definately put the smaller 110 needle in the primary bowl and/or get a pump with return spring that keeps pressure below 7 psi.
I hate to spend your money, but I think that's worth it. There's not a lot of options for fuel pumps on LA engines with the '70 up waterpump. I found good pressure control and volume delivery using Holley's 'Keith Dorton' 110 mechanical pump, but its over 10 years old. I'd like to think new ones still the same internally, but I don't know that for sure.

Nice thing about the clear sight plugs on your fuel bowls is that you can see if the level has risen or fallen since you set it.
If you do need to dump some fuel out of a bowl in an emergency, back off a bowl screw and drain it into a sardine can or whatever. I've even had to use a rag - hardly the best the choice but prob better than dumping on the engine.... :(
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I do have another .110 n/s that I bought. I could install that, but i'm not sure how much it would bring the pressure down when going from .120 that is already installed in the primary. I'll look into getting a different gauge like the other fella suggested.
 
DartThis74 said:
I do have another .110 n/s that I bought. I could install that, but i'm not sure how much it would bring the pressure down when going from .120 that is already installed in the primary. I'll look into getting a different gauge like the other fella suggested.
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It's not going to bring pressure down.
It's less likely to be pushed or held open by the pressure in the line.
 
DartThis74 said:
Could be a crapped out summit brand gauge ?
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Is the fuel pump adjustable, manual or electric? The reason you want to double or triple check the fuel pressure is that not only could the gauge be high it could also be too low. Too much fuel pressure can blow the needle off the seat and cause flooding vs too little the engine will starve. Some of the vacuum gauge kits can also check pressure, so a good vacuum gauge is always nice to have.
 
69FBCuda said:
Is the fuel pump adjustable, manual or electric? The reason you want to double or triple check the fuel pressure is that not only could the gauge be high it could also be too low. Too much fuel pressure can blow the needle off the seat and cause flooding vs too little the engine will starve.
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standard mechanical fuel pump on small block 360.
 
You got it.
Look at the drawing on page 4 above for the effect. But I think you got it,

pressure x area = force to keep the valve shut.

.110" diameter
7 lb/sq in x 3.14 x .55 x.55 = 6.6 lbs force

.120" diameter
7 lbs/sq in x 3.14 x .6 X .6 =7.9 lbs force
 
Mattax said:
You got it.
.110" diameter
7 lb/sq in x 3.14 x .55 x.55 = 6.6 lbs force

.120" diameter
7 lbs/sq in x 3.14 x .6 X .6 =7.9 lbs force
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Just saw this thread.
The force does increase by the square of the diameter - but you're off by a decimal place there (should be .055 and .060 squared). That brings the numbers down by a factor of 100, i.e. 0.066 and 0.079 lbs force. It'd take a pretty big float to push a needle closed against 6-8 pounds of force trying to open it! :)
 
yellow rose said:
Also, if you run an electric pump, make sure the engine is running when you set the float level.
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Why do you do that? Just wondering as I thought a nice perc of an electric pump was the ability to set floats on a still motor..? Its a messy job when its idling if your new to it (like me) fuel squirting everywhere! Always seemed to have Carters or 'brocks where you could set the float level properly when its apart.
 
What messes people up is the two methods Holley describes to set float level are the same. With the sight plugs removed, you adjust so the fuel dribbles out. How in the hell could you adjust the fuel level halfway up the hole with the frikkin plug out? With the clear plugs, you adjust the level until you see the fuel halfway up the sight glass. It's the same exact level in both circumstances. If you put the clear plug in where you adjusted the solid brass plug to just trickle out, you would see the level would be about halfway up.

Also, regarding why the needle assembly is so low on the carburetor, the float is bent. If you readjust it, that will fix that problem.
 
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pishta said:
Why do you do that? Just wondering as I thought a nice perc of an electric pump was the ability to set floats on a still motor..? Its a messy job when its idling if your new to it (like me) fuel squirting everywhere! Always seemed to have Carters or 'brocks where you could set the float level properly when its apart.
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That gives the most accurate adjustment. You can argue it's splittin hairs and it is kinda, but if you're lookin for the dead most accurate float level, that'll give it to you. Big race cars usually adjust in that manner.
 
pishta said:
Why do you do that? Just wondering as I thought a nice perc of an electric pump was the ability to set floats on a still motor..? Its a messy job when its idling if your new to it (like me) fuel squirting everywhere! Always seemed to have Carters or 'brocks where you could set the float level properly when its apart.
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Rusty gave the short answer and it’s correct.

The carb behaves differently when there is fuel moving through it at idle, compared to when there is no fuel moving through it.


You have to remember that there are air bleeds involved and at least one emulsion hole above the fuel level that can change the fuel level from the engine not running and running.

Sometimes it doesn’t make a difference and sometimes it does. That’s why I just always set the final fuel pressure when the engine is running.

BTW, I have been using some washer/seals from BLP under the adjusting nut and under the lock screw. They are white and I think they said they are Teflon, or maybe they said they weren’t.

At any rate, for whatever reason, those things let almost zero fuel past them when setting the float level. They are much nicer than the paper junk that comes in most kits.
 
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