My carburetor keeps dumping gas

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67DodgeDart360

67DodgeDart360

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My carburetor keeps dumping gas when it conks out. I have a 360 engine with a holly carburetor. I can hear the gas. Is this a carburetor issue or could this be a timing issue? And it doesn’t seem to idle right. Even when I put that idle screw in or out. Let me know what I can do. I also have a different holly carburetor I can try if nothing works. Let me know your thoughts. Thanks
 
If carb tuning isnt your thing,than hollEy isnt for you.
Buddy had a similar issue,bolted on an edelbrock and has been trouble free since.

for the knowledgeable guys willing to educate you on the finer points of holley tuning you will need to post up more details about the engine....
 
67DodgeDart360 said:
My carburetor keeps dumping gas when it conks out. I have a 360 engine with a holly carburetor. I can hear the gas. Is this a carburetor issue or could this be a timing issue? And it doesn’t seem to idle right. Even when I put that idle screw in or out. Let me know what I can do. I also have a different holly carburetor I can try if nothing works. Let me know your thoughts. Thanks
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Could be float adjustment, a heavy float (half full of gas), a bad needle and seat (or full of sediment), or even too much fuel pressure.
 
We need more information about the combination & the carb. What TMM said may be part, or all of your problem.
 
67DodgeDart360 said:
My carburetor keeps dumping gas when it conks out. I have a 360 engine with a holly carburetor. I can hear the gas. Is this a carburetor issue or could this be a timing issue? And it doesn’t seem to idle right. Even when I put that idle screw in or out. Let me know what I can do. I also have a different holly carburetor I can try if nothing works. Let me know your thoughts. Thanks
Click to expand...

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67DodgeDart360 said:
My carburetor keeps dumping gas when it conks out.
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In general, if fuel is coming out from the carb bowls then its an overfilling issue of some sort.
Describe what you see/hear/smell when it 'dumps gas'
 
7855 is the engineering list number for a 4175 spreadbore model. Nominal flow rating of 650 cfm.

It bothers me to see an epoxy repair like that on the bowl. Looks like its above the inlet valve.
Could be functional for a while, but just raises questions.
 
Tooljunkie said:
If carb tuning isnt your thing,than hollEy isnt for you.
Buddy had a similar issue,bolted on an edelbrock and has been trouble free since.

for the knowledgeable guys willing to educate you on the finer points of holley tuning you will need to post up more details about the engine....
Click to expand...

Truer words have never been spoken!!!
 
There is nothing wrong with epoxy on that plug. If you undo the crimp on the die cast to replace the o-ring on the aluminum plug, most likely there won’t be enough diecast left to recrimp. You can take out the N&S and clean up everything out real good and try it again. While there is almost no carb that can’t be made to run right, those spreadbores often prove to be more trouble than they are worth.
 
67DodgeDart360 said:
My carburetor keeps dumping gas when it conks out. I have a 360 engine with a holly carburetor. I can hear the gas. Is this a carburetor issue or could this be a timing issue? And it doesn’t seem to idle right. Even when I put that idle screw in or out. Let me know what I can do. I also have a different holly carburetor I can try if nothing works. Let me know your thoughts. Thanks
Click to expand...

These are my thoughts;
1) When it conks out, get out and open the hood as fast as you can; if you can hear "sizzling" right away, then pop the air cleaner off and look for "smoke coming up out of the intake, and a strong smell of gas..
If all 4 of these events are happening simultaneously, then one or both of your float valves is not shutting off. Then You get to figure out why.

2) but if the sizzling doesn't come until later, then you have at least two problems; namely the one that caused the engine to conk out, and the second is causing fuel percolation.
 
Dana said:
There is nothing wrong with epoxy on that plug. If you undo the crimp on the die cast to replace the o-ring on the aluminum plug, most likely there won’t be enough diecast left to recrimp. You can take out the N&S and clean up everything out real good and try it again. While there is almost no carb that can’t be made to run right, those spreadbores often prove to be more trouble than they are worth.
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Yes there is. Look closely. That's the set screw and adjusting nut for the front float bowl that's been epoxied over. Look CLOSE. You can see the hex of the nut.

To the OP that carburetor is someone's factory Holley for a spread bore manifold. It's not an aftermarket replacement. It either came on a GM or Chrysler product, most likely Chrysler, since it has Chrysler throttle linkage. Find another carburetor. That one has very lean circuits. That coupled with the epoxy on the float adjuster and I say throw it in the trash.
 
I would **** can that carb. That looks like a Thermoquad replacement carb and weren't made like the 4150 4160 series carbs. Not necessarily rebuildable and hard to get parts for I imagine. I put one of those on my 73 Challenger in the late 70's. That carb us probably 50 years old.
 
I think I will try a different carburetor. I purchased a new holly carburetor a year ago. I think I will try that. I will just need to use a adapter plate. It’s 4.25” to 5” carburetor.
 
67DodgeDart360 said:
I think I will try a different carburetor. I purchased a new holly carburetor a year ago. I think I will try that. I will just need to use a adapter plate. It’s 4.25” to 5” carburetor.
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I see, so that's like an early AFB, right? That could be a good choice if it's in good shape. They were fine carburetors. A little on the lean side, but probably not as bad as what you have now. Keep us posted.
 
RustyRatRod said:
Yes there is. Look closely. That's the set screw and adjusting nut for the front float bowl that's been epoxied over. Look CLOSE. You can see the hex of the nut.

To the OP that carburetor is someone's factory Holley for a spread bore manifold. It's not an aftermarket replacement. It either came on a GM or Chrysler product, most likely Chrysler, since it has Chrysler throttle linkage. Find another carburetor. That one has very lean circuits. That coupled with the epoxy on the float adjuster and I say throw it in the trash.
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Rob...hate to disagree, but, no it's not adjustable. Here's pic of another carb...

s-l1600.jpg
 
65Val said:
Rob...hate to disagree, but, no it's not adjustable. Here's pic of another carb...

View attachment 1715561678
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Look how BIG the epoxied area is compared to the one on the rear. There surely appears to be a hex under "all that". There's certainly "something" under there "besides" epoxy.
 
Also consider the possibility of running a Thermoquad! That's what the Chrysler engineers specified, and you can play with the mixture jets and rods all you want.
 
Bill Crowell said:
Also consider the possibility of running a Thermoquad! That's what the Chrysler engineers specified, and you can play with the mixture jets and rods all you want.
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Actually, Bill, that's a factory carb put on mid 70's 440's in Chryslers..they were used when they phased out the ThermoQuads/QuadraJets.
 
RustyRatRod said:
Look how BIG the epoxied area is compared to the one on the rear. There surely appears to be a hex under "all that". There's certainly "something" under there "besides" epoxy.
Click to expand...
That is an old-style non-racing Holley, and they are adjusted internally, like the majority of street carbs.
What's under that epoxy, is the same as what you see on the rear bowl. I wouldn't say that those plugs are prone to leakage, but ..... I've seen a few epoxied up like that.
 
AJ/FormS said:
That is an old-style non-racing Holley, and they are adjusted internally, like the majority of street carbs.
What's under that epoxy, is the same as what you see on the rear bowl. I wouldn't say that those plugs are prone to leakage, but ..... I've seen a few epoxied up like that.
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I changed the carburetor and it runs great! Thanks everyone for all the information.
 
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