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Old 09-17-2020, 04:47 PM   #1
wbmoore
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Holley questions

Just bought a truck with a big block (PO said 366, glovebox says 427...does not matter). It has a Holley ??? that would not start if left for a day. Sort of fixed that with an electric pump.

The new questions are: can the fuel bowls (circled in blue) be removed with the carburetor still on the engine ? Can they be removed without losing all the magical innards ? And most importantly, can they be reinstalled just as easily ?

The carburetor is leaking, front and rear, from the bottom of the bowls. I‘ve tightened the four screws which hold each bowl on and the leaks did get better. I can see the screws for the plates on the bottom but it is impossible to tighten them. This appears to be where the leaks are.

Also, can anyone ID the model of this carb so I can look for parts ?

I’m trying to get this engine working reliably and safely now. I’ll take more time to fix it properly after it’s been raining for a month.

Thanks.
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Old 09-17-2020, 05:08 PM   #2
Ziegelsteinfaust
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Re: Holley questions

Yes they can be removed. All they hold is fuel.
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Old 09-17-2020, 05:14 PM   #3
Ziegelsteinfaust
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Re: Holley questions

You would have to run the numbers you find on the carb. Usually a 4 diget code.

The carb is the most basic holley, and you front jets with a rear metering block.

It is fully upgradable to have front, and rear jet blocks.
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Old 09-17-2020, 06:33 PM   #4
geezer#99
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Re: Holley questions

Good luck pulling the bowls and not tearing the gaskets.
You’ll need to remove the carb to fix the leaks.

Carb kit will need your carb number so you get the right one.
Carb number is on the choke horn just to the drivers side of the vent hole.

What electric pump did you use and what pressure is it rated at?
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Old 09-17-2020, 06:43 PM   #5
wbmoore
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Re: Holley questions

Here are the numbers I can see: on the front of the choke plate chamber... 203097B LIST-8283 3528. On the 1/2” thick plate behind the front fuel bowl it says: 9251 8283. Looking straight down the throats it says: 6R 5568 B. The plate in front of the rear fuel bowl says: ???? followed by 8283

All seem like part numbers to my ignorant mind.

Thanks.
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Old 09-17-2020, 07:12 PM   #6
geezer#99
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Re: Holley questions

List - 8283 is likely what you need.
Kit here.


https://quadrajetparts.com/holley-41...mc-p-1556.html

And one here with a pic of your carb so you know it matches..

https://www.carburetion.com/CarbNumber.asp?Number=R8283
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Old 09-17-2020, 07:15 PM   #7
wbmoore
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Re: Holley questions

Geezer.....the pump I used is a Facet box type that was in my box marked Fuel Pumps an filters. They make two: 1.5-4 psi and a 4-7 psi so it’s a 50/50 thing. Didn’t put a regulator on because my gauges are all fubar. Maybe that’s the NEW problem....too Much pressure.

The Holley fuel bowls looks to have some plate with a diaphragm, etc.screwed on the bottom. This looks like where the leaks are coming from. I’m hoping to remove the fuel bowls, replace all the gaskets (along with ???), tighten everything up and go on down the road.....which usually never happens.

The engine is running (and starting-Thanks) for now. Just need to keep it going for 3 or 4 months to run the pumps.....then make it right.

Sounds like the 203097B LIST-8283 3528 might be the number.

THANKS to you both.
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Old 09-17-2020, 07:31 PM   #8
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Re: Holley questions

That plate at the bottom of the bowl is the accelerator pump diaphragms.
Holley will handle 7 psi.
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Old 09-30-2020, 08:00 PM   #9
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Re: Holley questions

I don't recognize that bowl design (but maybe it's just another flavor of the 4160 with a side-hung floats?). But yes, Holley typically has the accelerator pump bolted to the bottom of the primary bowl. Typically, there are a diaphragm, spring, and check valve inside. It's fresh in my mind because just two weeks ago I replaced my accelerator pump parts on my Street Avenger 770 (just your basic 4150 carb with center-hung floats behind all of that marketing). I replaced the diaphragm and check valve, but reused the original spring.

If the diaphragm had sprung a leak it could well explain your symptoms -- and be dangerous because of the extra gas spilled on top of the engine. Glad you're fixing it. Holley's are pretty straightforward and fun to fiddle with. (Not sure why some guys like the Edelbrocks.)
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