The holley 465 predicament...

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Blender

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hello fellow minirider members, some of you may have seen the troubles about this carbuerettor i posted in the Im just doing thread, so instead of hijacking it some more, i decided to make 1.
So heres the story. This carb has never run right. we bought it as a reco jobbie, done by Hume performance. we have replaced floats, powervalve, jets and spent endless hours tuning this thing. so here is what its doing:
A) It is iethere starving for fuel, or flooding.
B)It has a massive problem with the needle and seat for the secondaries. The needle and seat gets stuck, and the car flood immediately. we have done a full strip down and clean out, but it was as cleane as a whistle.
C)The floats seem to have a mind of their own (well mainly the secondaries) it was mainly getting stuck/sticking. so we bought a new brass float to replace the plast one. it made a difference, for about 2 days, then went back to the normal crap of sticking, etc
So thats it. we adjusted the accelerator pump this morning, it didnt actually need it though, so we cant think of what to do next. any help would be much apreciated.
 

my67xr

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so when you set the float level in the rear fuel bowl, is the fuel bowl full?

do you have the brass sight plug out of the carby,
and adjust the needle and seat nut to have it just wet on the bottom of the sight plug holes' threads ?
 

Blender

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yes, we have st floats perfectly, so just a tiny weep comes seeps out, and after that it does run well, for about 5 minutes though. we think it could be a un-even fuel pressure contributing to our problems. we have a gauge, but we cannot find the right adeapter for it, so its not much use iether...
 

my67xr

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first thing i would do is to remove the needle and seat from the rear of float bowl.
so hold the nut with a 5/8" spanner, and use a big flat headed screwdriver to undo the locking screw on top.
once the screw is out, then use the nut if you can, to undo the needle/seat and remove it from the carb.

once you have it out,
check that the rubber tip of the needle is not perished at all, you casn see through the side of the seat, and check that there are no foreign bodies in it.
and also check there are no nicks/damage in the rubber o'ring, on the outside of the seat.
blow it out well with compressed air.



so if it looks good, then you can refit the needle/seat,
if you have some, put a thin smear of rubber grease on the outer o'ring, to help it go back in.
wind it in by hand using the nut.
a good base setting for the float height is to wind the needle/seat into the fuel bowl, until the top of the needle and seat just sticks out the top of the nut.
make sure there is a gasket on either side of the nut too.
now refit the screw and nip it up (dont lock it firm at this stage) while holding the adjustment nut from turning.

remove the brass sight plug from the fuel bowl, and start the car up.
maybe put a rag below it, under the bowl, just to catch any fuel that spills out.

the car should run. with just a hint of fuel dribbling out of the bottom of the sight plug hole thread.
if it is gushing out, then the needle/seat needs to be lowered.
so turn the car off again.
and loosen the locking screw 1.5 turns, and then turn the nut clockwise half a turn to lower the needle,
and then nip up the locking screw again.
start up the car again, and check the fuel height at the sight plug, if it is still too high then turn the car off and lower it a touch more, then try again.



post up your results
 

my67xr

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what fuel pump are you using, standard mechanical or electric?

is the fuel line from the pump to the carby newish?
sometimes when you slip the rubber hose over the barb, some rubber bits will come off, and cause problems in your needle/seats
 

my67xr

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with there being so many different model Holleys 465's made over the years,
can i confirm which model exactly you have, is it a 1848-1 ?
the model number is stamped at the top front of the choke tower

a photo of your dads setup might help too ?
 

Blender

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what fuel pump are you using, standard mechanical or electric?

is the fuel line from the pump to the carby newish?
sometimes when you slip the rubber hose over the barb, some rubber bits will come off, and cause problems in your needle/seats
we were using one of those holley blue's, (electric) but it blew a seal, that you cant replace iether, holley dont make re-build kits for em...
so we got a copy. im not sure what it is, but its fairly new, 2-3 months old now. same with fuel line, its all fairly new, old mans at work atm, so no car here, will be working on it this arvo no doubt lol
 

my67xr

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did you use the regulator that come with it?
the maximum pressure a standard Holley needle and seat needs is about 6psi, up to 9psi (the latter is used when drag racing etc}
otherwise they can over ride the needle and seat shut off, and flood.


i have rebuilt a heap of Holley Blue pumps?

Holley Blue rebuild kit 12-811, contains new base seal, new rotor, new vanes.


Holley Blue check valve and filter rebuild kit 12-806, contains new base gasket, new check valve, new check valve rubber seat, new filter gauze, new o'ring, and new spring.







when you say it runs good for 5 mins then floods, so there is fuel pouring out of the rear breather spout ?
 

Blender

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wow, didnt know that about the holley blues. well we've still got it, might re-build it down the track.
it runs fine for 5 minutes and then the floats stick, causing it to iether flood or starve. it just seems so il-logical...
If it helps, the inlet manifold is an edelbrock performance manifold.
 

my67xr

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so you don't know if it is flooding or starving ?
starving for fuel it would have nothing when you go to accelerate,
flooding it will gurgle, and carry on running really bad, needing lots of throttle etc, while chugging black smoke/unburnt fuel out the exhaust


the china Holley copy pumps are pretty badly made.

do you have a decent fuel filter mounted before the pump, so fuel is filtered before it reaches the pump?

if not, i think i know what is wrong, you are loosing fuel pressure through the check valve?
 

Blender

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lol, no i mean it does iether starve or flood.
We have one of those brass type filters, and another 2 before fuel reaches the carb.

Sounds like we got a bit of work to do this arvo :)
 

my67xr

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ok,
i'm not sure what brass filter you mean though, pics or link to one ?


i will leave it at that until your dad and the car come home.
then we can go on from there.


i reckon it will be an easy fix though ?
hopefully :cheeky-smiley-005:
 

my67xr

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when your dad gets home, can you get some photo's for me? or is that still a problem ?

i need one of the filter between the tank and pump
one of the pump,
one for the other inline filters
and 2 pics of the actual carby, one from the accelerator side,
and one from the front, looking down at an angle at it.



i'm pretty sure i have a Holley Blue spare here,
i will try and get some pictures, so it will help to explain what i want you to do.
 

Blender

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will do mate, we're ready to try anything, do you mean the pump on the car atm, or the holley?
Im still having some problems with photobucket atm, but im hoping google chrome will fix that.
 

my67xr

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i use chrome now, switched late last year from IE.

we can start by /checking sorting the pump on the car now.
 

Phil67

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Longgg time since I've played witha 465! I reckon Craig is on it with fuel pressure, or power valve. I would also take the ball bearing out of the vac secondary diaphragm, gives yes more snap, but not until you sort it of course. What engine is it on? Is it direct bolted to the manifold? Manifold getting hot is it and vaporising the fuel in the bowl? Used to happen on my 327 hk Monaro, drove me nuts, put a spacer on it and bingo, fixed.
 

Blender

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with there being so many different model Holleys 465's made over the years,
can i confirm which model exactly you have, is it a 1848-1 ?
the model number is stamped at the top front of the choke tower

a photo of your dads setup might help too ?
alright, the old mans not too fussed about putting photos up, but the carb is a 1848-1.
We had a bit of a mess around with it this morning, adjusting the floats. the were a bit low. once we set them right, we drove off, it went well for about 5 minutes,then went to crap. when we stay at a certain rpm, it chugs, its hard to explain, we think it might be because of varying fuel pressure, but we cant set it, because there is no adapter for it anywhere....
 

my67xr

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so are you just running the original Holley Blue Regulator set as it come ?
if so that's ok, they are normally around 6-7 psi from the factory.


the photo's were to help me diagnose it, they may have shown me something obvious.


i would start by checking/cleaning the filter screen in the bottom of the pump.
if you have a rubber fuel hose feeding the pump, clamp it off so no fuel will leak out.
then remove the 4 screws holding the bottom cover of the pump on.
the plate will then come off, and the rubber seal.
quickly dry off the rubber seal as it will expand while it is wet with fuel.
the rotor and vanes might drop out, with the disc that holds them in, they're easy to refit when reassembling the pump again.
check that the vanes can slide in and out of the rotor slots, and that none are rusty, as this can cause them to stick and not throw out when the pump is spinning
towards the back of the pump you will see the brass or stainless filter screen, slip it out and clean it up, it could have dirt/debris lodged in it.

last thing to do is look at the check valve.
the large flat headed screw at the back of the pump (next to the inlet barb) needs to be undone.
there is a spring behind the screw, then the check valve can come out
look at the rubber seat in the valve and check that there is no grains of dirt etc sitting where it seals
(you should see a ring where the valve seats in the rubber)
as this will not let the pump get up to a decent pressure.

if everything looks good it can be reassembled,
and don't over tighten the 4 screws on the bottom of the pump when you do them up, it can bind up the pump.


let me know what you find
 

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