Holley 1920 Help needed

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Ramonsito

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Hello,

I just purchased and installed a Holley 1920 on my '69 A100 Van, slant six and it starts great and runs pretty good, a little rough on acceleration but it idles nicely.
The problem is I was smelling gas fumes and searched for leaks - there are none I could find but as I was searching (with the motor off) I noticed the vacuum valve all of a sudden open up and spurt gas.
Any ideas why this would happen and how to fix it would be appreciated!
Raymond
 
Not sure but most people reccomend rebuilding the carb yourself with a kit such as walker found at orileys, rather than buying a refurb. Have you tried slantsix.org? I rebuilt mine and it's pretty easy.
 
By vacuum valve i assume you mean Power Valve or "Economizer" Valve? and when you say it spurt out, out of where?
 
It's a one barrel. They suck. Throw it in the ditch.
 
When looking at the diagram, it's called the bowl vent valve (black rubber ring) and it is usually in the up position until you step on the gas pedal and then it goes down or closes.
I just had a thought, it was in the down position with the motor off, instead of up, and then it just popped up/open and gas came out from under it.
I'm thinking it should have been in the up/open position with the motor off and foot off the gas pedal, but for some reason it was down, is that correct?
 
Ramonsito said:
When looking at the diagram, it's called the bowl vent valve (black rubber ring) and it is usually in the up position until you step on the gas pedal and then it goes down or closes.
I just had a thought, it was in the down position with the motor off, instead of up, and then it just popped up/open and gas came out from under it.
I'm thinking it should have been in the up/open position with the motor off and foot off the gas pedal, but for some reason it was down, is that correct?
Click to expand...

with that said you must have a smog carb, not a bad thing it just has the hose bib and valve. and your correct, the valve should be down (or closed) to route vapor's thru the bowl vent in down the throat vs open, out the bib and into the charcoal canister. now if you have fuel coming out either your float level is so high its pushing it out (does it run fine??) or maybe the canister or line is plugged and fuel vapors are building up in the line and condensation.

57dodged100 said:
slantsix.org has a wealth of info. Check this link:

http://www.slantsix.org/forum/viewtopic.php?t=33102

My properly tuned 1920 runs fine. If you want to go bigger, I'm pretty sure you will need to change intakes.
Click to expand...

unless you get into some DIY stuff but an offy or clifford is a better intake
 
805moparkid said:
i know i can wait to find a 400-500 cfm small holley for the offy so i can get the swinger in good shape!
Click to expand...

I gotta real nice 4412 500 I am not gonna use. It might bolt on and run but I would kit it.
 
I gave you the list number, dork.
 
It runs a little rough, idles just fine, when you say the line or canister is plugged, what do you mean?
I does not have the smog crap - it's all original 1969.
 
Ramonsito said:
It runs a little rough, idles just fine, when you say the line or canister is plugged, what do you mean?
I does not have the smog crap - it's all original 1969.
Click to expand...

can you take a pic of the carb with the air cleaner off?
 
You can adjust the bowl vent valve by bending the steel tab but the measurements depend on year. The kit I mentioned has detailed instructions.
 
The bowl vent is usually open at idle and closes when you open the throttle. The real issue is that the float may be set too high. Either there is junk in the needle and seat or the float level is set too high. Pull the bowl off and invert the bowl. The seam in the float should be parallel with the bottom or top edge of the bowl. If not bend the float lever to adjust. If it is level then pull the float out and look for a dad needle and seat valve. And see if there's any junk, like rust or sediment floating around in the fuel bowl. You DID put a new fuel filter on the car before running that new carb, yes?

Guys, there's nothing wrong with a 1920 carb - thousands of motors have left the factory with them.
 
Invert the carb as shown, the top edge of the float should be parallel with the top edge of the bowl. Bend the bent tab that is pushing on the needle valve which ever way it needs to go to get the float level with that edge. In this pic the float appears to be too low. If its too high the car and bowl can flood. Or the needle and seat has junk in it or is otherwise damaged the fuel will not shut off and the pump will also flood the motor.
 

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Lucky you have a good Holley 1920. I went thru many long ago before I got a good one. If yours looks like airgrabber's photo (pre-smog, i.e. no big vent tube off the bowl), then your bowl vent should be open at idle (rubber disk at bottom of photo, i.e. top of carb). As mentioned, bend the rod to make that true. I also agree that your float is probably not shutting off fully, so the left-over pressure in the fuel line causes slight flow into the bowl until it overflows. It is easy to remove the inlet fitting and needle and inspect or replace.

There were 2 other 1-bbl carbs for the slant that I know of. The Carter BBS was on early engines. It is very similar to the ubiquitous 2-bbl BBD that came on most 318 engines. You can find manuals free on-line (I did). The Holley 1945 was later. Some people love those. In general, Carter's are simple and robust but Holley's work better when they aren't ****ed up. I think there was a Holley Economaster version for the slant in the 80's for better mileage, but sounds like you want power.
 
Thank you airgrabber!I opened the bowl and not only was the float off, but the spring was sitting in the corner. It must have come off in shipping or was never put on correctly! It's not spewing gas and the valve stays open like it should. It's still hesitates at acceleration from a standstill, but starts right up and idles nicely.
Raymond
 
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