holley idle adjustments
Thread Starter
|
Senior User
Joined: Dec 2007
Posts: 178
Likes: 0
holley idle adjustments
The carb on my 460 in my truck is acting funny. It almost sounds like a dragster It Idles really rough. I tried setting the Idle mixture screws on the side of the metering block. I bottomed them out and them turned them out 1 1/4 turns. I started turning them in till I got the highest reading on my vacuum gauge, about 13 hg. The screws are only about 1/4 turn from being bottomed out. It was running smoother, then it stalled when I restarted it, it started running really rough again.
The exhaust smells of gas. I turned the screws all the way in just to see what would happen, I thought it should stall but it didn't.
I had my timing light hooked up and checked it now and then during all of this and it didn't change at all.
I am about out of ideas. The screws had almost no resistance to turning, shouldn't they have some resistance?
The exhaust smells of gas. I turned the screws all the way in just to see what would happen, I thought it should stall but it didn't.
I had my timing light hooked up and checked it now and then during all of this and it didn't change at all.
I am about out of ideas. The screws had almost no resistance to turning, shouldn't they have some resistance?
Tuned
Joined: Apr 2011
Posts: 298
Likes: 4
From: Highland CA
The carb on my 460 in my truck is acting funny. It almost sounds like a dragster It Idles really rough. I tried setting the Idle mixture screws on the side of the metering block. I bottomed them out and them turned them out 1 1/4 turns. I started turning them in till I got the highest reading on my vacuum gauge, about 13 hg. The screws are only about 1/4 turn from being bottomed out. It was running smoother, then it stalled when I restarted it, it started running really rough again.
The exhaust smells of gas. I turned the screws all the way in just to see what would happen, I thought it should stall but it didn't.
I had my timing light hooked up and checked it now and then during all of this and it didn't change at all.
I am about out of ideas. The screws had almost no resistance to turning, shouldn't they have some resistance?
The exhaust smells of gas. I turned the screws all the way in just to see what would happen, I thought it should stall but it didn't.
I had my timing light hooked up and checked it now and then during all of this and it didn't change at all.
I am about out of ideas. The screws had almost no resistance to turning, shouldn't they have some resistance?
Moderator
Joined: Dec 2001
Posts: 22,436
Likes: 17
From: Louisville,Ky.
Need the list number from the choke horn.
Either the float is too high, Debris in the needle and seat (look for gas dropping into the carb from the boosters at idle, should be none) or a blown power valve.
Either the float is too high, Debris in the needle and seat (look for gas dropping into the carb from the boosters at idle, should be none) or a blown power valve.
Thread Starter
|
Senior User
Joined: Dec 2007
Posts: 178
Likes: 0
I went to the nhra drag races at Norwalk this weekend and talked to the rep in the holley tent. I explained what was happening to him. He said the problem is the stuff that passes for gas now. Basically moisture combines with the alcohol in the gas to screw with the seal on the needle and seat. The gas leaks past the needle and finds its way into into the boosters as lxman said causing it to run way rich. Usually on the third trip to the hardware store on a Saturday it runs fine. which sorta confirms his diagnosis. Guess I just got to drive more.
Thread
Thread Starter
Forum
Replies
Last Post
Squirrel Man Sam
FE & FT Big Block V8 (332, 352, 360, 390, 406, 410, 427, 428)
14
Jun 30, 2023 01:05 PM
retro48/52
Big Block V8 - 385 Series (6.1/370, 7.0/429, 7.5/460)
2
Jul 29, 2011 02:21 PM
3speed
Fuel Injection, Carburetion & Fuel System
6
Jan 27, 2004 09:32 AM
