EXTREMELY RICH Holley
Thread Starter
Drifting
Joined: Mar 2001
Posts: 1,896
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EXTREMELY RICH Holley
Today I slapped my Holley on my shop teachers 350HP truck motor. And we tried for two ours to get the damn thing to lean out enough. It went through 3 GALLONS of gas in 30-40 minutes at IDLE!! We turned the idle air screws all the way in, turned the floats all the way to the point where it killed the motor and it still ran to rich. The weird thing is that, that same carb was on the truck 8 weeks before and it ran beautiful....sang like a true beast. All I've done since is rebuild it (just replaced gaskets) and didn't change anything what-so-ever. And my teacher is a Holley expert. Just for some odd reason we can get it to lean out. I think my meetering block is hosed. We didn't changet the jets or anything so we don't know what the problem is. But, I'm trying to get a job at AutoZone so, I can get a new chrome Holley 600 for 216$ and 180 on an employee discount.
[Modified by Aaron-74, 4:23 PM 3/22/2002]
[Modified by Aaron-74, 4:23 PM 3/22/2002]
Melting Slicks
Joined: Oct 2001
Posts: 2,064
Likes: 1,382
From: Halifax, Nova Scotia, Canada
Re: EXTREMELY RICH Holley (Aaron-74)
A bad power valve will give that exact same problem. Also, I assume the metering block gasket is the correct one for that carb.
If the float levels are fine, then I would change the power valve.
Someone may have another suggestion, but I can't think what else it might be.
Barry
If the float levels are fine, then I would change the power valve.
Someone may have another suggestion, but I can't think what else it might be.
Barry
Safety Car
Joined: Aug 2000
Posts: 3,909
Likes: 26
From: Clymer PA
Re: EXTREMELY RICH Holley (Aaron-74)
Have you checked the power valve to make sure it's good? A bad power valve on a Holley will do strange things. It only takes one backfire to ruin a power valve...
Drifting
Joined: Nov 2001
Posts: 1,502
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From: Elyria Ohio
Re: EXTREMELY RICH Holley (Aaron-74)
I agree a bad power valve. I had the same thing happen just a couple weeks ago. I have an extra brand new one if you want it. They are cheap though. I was getting 4 mpg. while the car was idleing It would burn your eyes with a 10 mph wind out in the drive way. We still don`t have any misquitoes (SP).
You will find that will be your problem
Bob
You will find that will be your problem
Bob
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Thread Starter
Drifting
Joined: Mar 2001
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Re: EXTREMELY RICH Holley (76 Red)
Yeah, now that I think about it, it could be the power valve. With the motor running for about 5 minutes my eye's burned so bad it made them tear. It COULDN'T be a vacuum leak. The motor is brand-new and there is sealant every where that i can safely be. And we aslo checked and closed all ports that could be a leak. It's a new power valve though, and it was running real rich even before it back-fired. It could be the power valve, but i don't see how since it was doing that before anything happened that could cause it to go back. Hopefully I'll get this job and solve the problem in no time flat.
Le Mans Master
Joined: Mar 1999
Posts: 6,744
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From: delmont pa
Cruise-In I Veteran
Cruise-In II Veteran
Re: EXTREMELY RICH Holley (Aaron-74)
what is the LIST# on the front of the choke housing,knowing that we can see what you have and what should be in the carb. when you rebuilt it did you compare the gaskets you took off with the ones you put on because using the wrong gaskets will cause this problem. :chevy
[Modified by clem zahrobsky, 10:21 PM 3/22/2002]
[Modified by clem zahrobsky, 10:21 PM 3/22/2002]
Melting Slicks
Joined: Oct 2001
Posts: 2,064
Likes: 1,382
From: Halifax, Nova Scotia, Canada
Re: EXTREMELY RICH Holley (Aaron-74)
[QUOTE] It's a new power valve though, and it was running real rich even before it back-fired. It could be the power valve, but i don't see how since it was doing that before anything happened that could cause it to go back. /QUOTE]
The wrong power valve will also cause this problem. Power valves are rated for different vacuum levels. If you replaced the power valve with one that is rated higher than the engine's vacuum, then the power valve will never close, which causes the rich condition.
Was the number on the new power valve the same as the one removed.???
The wrong power valve will also cause this problem. Power valves are rated for different vacuum levels. If you replaced the power valve with one that is rated higher than the engine's vacuum, then the power valve will never close, which causes the rich condition.
Was the number on the new power valve the same as the one removed.???
Thread Starter
Drifting
Joined: Mar 2001
Posts: 1,896
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Re: EXTREMELY RICH Holley (Barry's70LT1)
Actually, dumb assed me didn't check that. It came in the re-build kit. So, I figured it was the correct power valve. If I could get the correct power valve number, that would be GREAT. I need to find my Holley rebuild box around here because It's got the right one in it...or the origanal one.
Race Director
Joined: Mar 1999
Posts: 10,258
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From: Calif.
Re: EXTREMELY RICH Holley (Aaron-74)
R80457-1
4160.
600 CFM.
Renew Kit: 37-119
Trick Kit: 37-993
Primary & Secondary Needle and Seat: 6-506
Primary Main Jet: 122-64
Secondary Main Jet (or plate): 134-39
Primary Metering Block: 134-128
Secondary Metering Block: 134-39
Primary Power Valve: 125-65
Primary Discharge Nozzle: .031"
Secondary Nozzle Size (or spring color): Black
Primary Bowl Gasket: 108-83-2
Primary Metering Block Gasket: 108-89-2
Secondary Bowl Gasket: 108-90-2
Secondary Metering Block Gasket: 108-90-2
Secondary Metering Plate Gasket: N/R
Primary Fuel Bowl: 134-101
Secondary Fuel Bowl: 134-105
Throttle Body & Shaft Assembly: 12R11240A
Venturi Diameter (Primary): 1 1/4"
Venturi Diameter (Secondary): 1 5/16"
Throttle Bore Diameter (Primary): 1 9/16"
Throttle Bore Diameter (Secondary): 1 9/16"
4160.
600 CFM.
Renew Kit: 37-119
Trick Kit: 37-993
Primary & Secondary Needle and Seat: 6-506
Primary Main Jet: 122-64
Secondary Main Jet (or plate): 134-39
Primary Metering Block: 134-128
Secondary Metering Block: 134-39
Primary Power Valve: 125-65
Primary Discharge Nozzle: .031"
Secondary Nozzle Size (or spring color): Black
Primary Bowl Gasket: 108-83-2
Primary Metering Block Gasket: 108-89-2
Secondary Bowl Gasket: 108-90-2
Secondary Metering Block Gasket: 108-90-2
Secondary Metering Plate Gasket: N/R
Primary Fuel Bowl: 134-101
Secondary Fuel Bowl: 134-105
Throttle Body & Shaft Assembly: 12R11240A
Venturi Diameter (Primary): 1 1/4"
Venturi Diameter (Secondary): 1 5/16"
Throttle Bore Diameter (Primary): 1 9/16"
Throttle Bore Diameter (Secondary): 1 9/16"
Drifting
Joined: Jan 2002
Posts: 1,645
Likes: 11
From: Schaumburg IL
Re: EXTREMELY RICH Holley (Aaron-74)
All I would like to add Aaron - 74: put a vacuum gauge on the manifold at idle and see what you are pulling. An incorrect P.V. or a damaged one that is around or below mainifold vacuum will start leaking fuel and ---- very rich.
One other thing is make sure the secondaries are not slightly open, idle gets screwed up PV pulls in etc. Just give them a slight push with a screw driver to make sure they are shut.
One other thing is make sure the secondaries are not slightly open, idle gets screwed up PV pulls in etc. Just give them a slight push with a screw driver to make sure they are shut.
Burning Brakes
Joined: Mar 2002
Posts: 803
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From: South San Francisco CA
Re: EXTREMELY RICH Holley (bigvette1)
Can you find the old power valve? If it's not that, you may have one of the gaskets installed incorrectly. All those little holes mean things and if you plug one up or expose one that shouldn't be exposed, it will cause you problems. Also, did you check your accelerator pump and follow the instructions for clearance?