holley 4175 leak
Thread Starter
Burning Brakes
Joined: Oct 2004
Posts: 801
Likes: 17
From: Middletown Delaware
holley 4175 leak
4175 is leaking out the acell pump discharge nozzle while set up on the bench in carb stand.( this will empty bowl float) levels normal all new gaskets. This carb has the umbrella check valve for the accel pump. The bowl where the umbrella valve seal sits was damaged during machining process and doubt I am getting a good seal. Will this cause my leak issue.
Dr. Detroit
Joined: Mar 2012
Posts: 10,097
Likes: 4,027
From: New Braunfels Texas
It is impossible for the squirter to empty the float bowl as it is higher than the float bowl unless something is pushing it out......kind of impossible on the carb stand.
You mean that touching nothing, fuel leaks from the squirter?
Jebby
You mean that touching nothing, fuel leaks from the squirter?
Jebby
Thread Starter
Burning Brakes
Joined: Oct 2004
Posts: 801
Likes: 17
From: Middletown Delaware
ok i just checked carb again from sitting last night and discharge nozzle is dry. I am still dripping fuel from throttle shaft on drivers side and gasket between base plate and thottle body is saturated.
Last edited by Dave Witman; Oct 25, 2021 at 10:18 AM.
Dr. Detroit
Joined: Mar 2012
Posts: 10,097
Likes: 4,027
From: New Braunfels Texas
I think you have the wrong primary metering plate gasket installed. You need to pull it apart and post a pic of the gasket, main body and metering block with the gasket on it.
Jebby
Jebby
Dr. Detroit
Joined: Mar 2012
Posts: 10,097
Likes: 4,027
From: New Braunfels Texas
It has the right gasket....and it is sealing. The only other thing it can be is the red circled accel pump transfer tube o-ring......and this would have to be combined with a VERY high float level for it to "siphon" out of the squirter. It would also leak into the cavity behind the power valve and soak the baseplate gasket.
That's all I have without having it in front of me......I have never seen the leakage issue you are describing while on the bench.
Jebby
Last edited by Jebbysan; Oct 25, 2021 at 02:23 PM.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Thread Starter
Burning Brakes
Joined: Oct 2004
Posts: 801
Likes: 17
From: Middletown Delaware
start engine run for 5 sec just to make sure float bowls are full Carefully remove carb and set on stand. After about 8 hours fuel starts dripping from throttle shaft on passenger side and my throttle body gasket is saturated with fuel. I talked to a carb re builder and he told me there is a problem with latest gasket material being used in holley carbs. The gaskets are acting like a sponge and when fuel saturated they start dripping. I am looking into this now .
Thread Starter
Burning Brakes
Joined: Oct 2004
Posts: 801
Likes: 17
From: Middletown Delaware
ok leak issue was bad power valve which was new and crappy power valve gasket. Ran vette today cruise afr was 12.7 with 62 primary jets installed 60 jets and afr staid the same. I have never seen this before.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
If the gaskets being used are permeable (heavy, un-impregnated paper/cardboard), they will leak. There is a lot of that garbage material out there in rebuild kits, these days. These shyster manufacturers just find ways to make 'junk' even worse and save a few pennies for themselves while we have to diagnose and deal with their "s4!+" parts.
Hope you are able to solve the problem. It looks like you have identified the culprit....
Hope you are able to solve the problem. It looks like you have identified the culprit....