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Holley carb has me at wit's end

7K views 23 replies 12 participants last post by  johnsongrass1 
#1 ·
Hi fellas. New member here. After reading all old posts and talking to all the "experts" I am at my wit's end.

I have a 750 cfm Holley vac secondary 4160 carb. It was a leaker from day one and has been gone thru twice by a well advertised carb expert on the West Coast and now Holley themselves have gone thru it and can't find anything wrong.

Problem is fuel pours out of bottom of carb with just the fuel pump on. Fuel levels are set correct (triple checked). Will get fuel pool on manifold on throttle linkage side. Can see some fuel on carb body just over the throttle shaft on secondary side. I have taken carb off engine with fuel bowls filled and fuel drips out of bottom of baseplate in so many places it is impossible to trace. I have actually drained 7 qts of fluid out of my oil pan of which only 5 qts was oil, the rest was gas!

Thought it might be fuel pressure but carb has leaked with gauge reading 3 PSI up to 6 PSI with engine not running!

Any help you could give this inexperienced carb tuner would be greatlly appreciated.
 
#4 ·
you might have the wrong gasket between the metering block and main body. There are two different styles with the diferrence between them being the area where the accelerator pump makes its transfer from metering block to main body just above the power valve. One gasket has just a hole, the other has a horseshoe cutout. If you require the gasket with the hole and use the one with the cutout, then there is no closed route for the fuel to pass and it ends up pouring out through the base plate.
 
#5 ·
Had a black lab purebred dog once. Was registered and I paid a lot of money for him. I could never break him from tearing up EVERYTHING he could find (bit my garden hoses into 2" long pieces), dug EVERY plan in the yard totally out of the ground. Put up with him for about a year but finally got fed up and took him to the pound.

You got one of those. Take that bad dog to the pound and get a new puppy.
 
#6 ·
Hey Willys36 I must have gotten your lab's brother, S O B did the same thing, ate hoses like dog treats and the yard looked like a mortar target, The final straw was when he ate the leg off a hundred year old dining table then dug a two foot deep hole in front of the house entry steps, DOG GONE!
 
#8 ·
Yeah, I hear what you guys are saying. Last time I got it back from the Carb Shop I said if it leaked I was going to take a sledge hammer to it and buy a Demon.

Could it be that my fuel pressure gage is bad? Brand new Earl's unit. If there was too much pressure would it build up in the bowls even after the pump was turned off causing it to leak?

I have a related question. Is it necessary to run a Holley "Blue" electric pump and matching regulator for a street driven car? Wouldn't a Holley "Red" pump be better for the street? Was given the Blue pump free (brand new in box) by a friend who decided to go to fuel injection and didn't need it.
 
#9 ·
It shouldn't make a big diffrence as long as both pumps were regulated at 7 PSI. If the pump were pushing off the needle and seat, then the floats would indeed fill up, and assuming no other leaks, the fuel would escape out the vent tubes. You would probably see it shoot out, sometimes as high as a few inches. The red pump is more suited to street use but I don't think that what the problem is.

My mother has a Chow that constantly barks at birds, at all hours of the night. How do you stop birds from flying over the house?. She will send him back.
 
#11 ·
I've always had troubles with holleys leaking fuel like mad.

Just think about who makes them "Ford", ever see a ford truck with a few miles on it? Look under it and you'll see that both the front and main seals on the engine drip out oil :p

Get yourself a nice quadrajet or predator carb :thumbup:

EDIT: It does sound like the float is not set right.
 
#14 ·
well i am about to get a holley 600cfm 1850 - 4 -1664 for $50 bucks. The thing will be goin on a 425 caddy engine i have in a beater 70 long bead chevy i have. The guys said that one of the accelerator valve gaskets is leaking, and that he is willing to fix it before he sales it. Does the pose a problem in the future.
 
#17 ·
Hey,if he garintees it to work,how can you go wrong for 50 bucks? Can you pay him after its running to be sure?
he garintees it to work or my money back. he said he had it runnin on a fbird two years ago. also will this 600 be enough for the 425 stock with stock trany.

i have a rochester qjet (17080272 2899-cms)on it now...do you think it would be better to rebuild that thing...it is not the original one...or get the holley with milled off butterfly.

ive been looking for the number dcoder but have no luck...any suggestions. i will keep looking.
 
#19 ·
that was goin to be my next question.

had anyone have a page to decode the quade...need to know what size it is.

gues i am stickin with the quad:thumbup:
 
#20 ·
cool rockin daddy said:
Yeah, I hear what you guys are saying. Last time I got it back from the Carb Shop I said if it leaked I was going to take a sledge hammer to it and buy a Demon.

Could it be that my fuel pressure gage is bad? Brand new Earl's unit. If there was too much pressure would it build up in the bowls even after the pump was turned off causing it to leak?

I have a related question. Is it necessary to run a Holley "Blue" electric pump and matching regulator for a street driven car? Wouldn't a Holley "Red" pump be better for the street? Was given the Blue pump free (brand new in box) by a friend who decided to go to fuel injection and didn't need it.
That is your problem. Holley fuel pressure regulators can't handle the pressure that their pumps put out. I have a blue pump. My float levels are either all over the place with it, or just flooding all of the time like yours is. Go back to a mechanical pump and keep the carb.

87442lover said:
I've always had troubles with holleys leaking fuel like mad.

Just think about who makes them "Ford", ever see a ford truck with a few miles on it? Look under it and you'll see that both the front and main seals on the engine drip out oil :p

Get yourself a nice quadrajet or predator carb :thumbup:

EDIT: It does sound like the float is not set right.
Ford doesn't make Holleys.

Ford's oil pans seal bad? How about Chevy and their retarded timing cover to pan seal. That takes the cake when it comes to being lame. Every manufacturer has their flaws.

As far as Holleys go, it is up to the owner of them to keep them clean. That is the number one enemy of a Holley. Dirt will wreak havoc on them every time. They are super sensitive to being clogged. If that is not okay with anyone, they can go by an Edelbrock and have less accurate metering potential and a slower car. It is as simple as that.
 
#21 ·
You know, I don't know how this thread got started again. I logged on today and saw it near the top of the page so I replied.

I should add that I did continue to have problems with that piece of crap Holley Blue pump and it's regulator. They have also found a resting place at the bottom of my scrap barrel as I put a Edelbrock high volume pump that is preset at 6-7 lbs. No problems since.

Why do us hotrodders make it so difficult on ourselves? GM put mechanical pumps on the tri-power 427, the LS-6 454, the 7,000 RPM Z-28 302, so why do we go to all the hassle of electric pumps? Just to be cool and run what we see in the mags and at the strip. So much of what we do is absolute overkill! I am at the age now where I just want the dang part to do what I want it to, when I want it to. I still make it look sanitary but I go the simple route whenever possible now.
 
#22 ·
I like the Carter electrics 'cause they are cheap, free up room in tight early framed engine comprtments, a broken diaphgram won't fill my crankcase with oil, cleaner look, quiet and super reliable. Never had a problem with them in many cars over 30 years. Just depends on what your experience has been I guess.
 
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