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rebuilding my 1962 carter yh carburetor... couple questions
Posted by: Boosted60 ()
Date: February 20, 2012 11:27PM

everything was going smoothly, until i reached the metering rod assembly...

1. In bob helts book, it says to adjust the metering rod arm, so that when the accelerator pump rod is fully depressed the top of the eyelet of the rod is just below the gasket mating surface...

the previous adjustment would cause the metering rod to fully bottom out before the metering rod arm would touch the pump lifter link...so i bent it slightly up...
now the eyelet is still below the gasket mating surface...however the metering rod bottoms out at the same time as the accelerator pump... is this correct? or does the metering rod not supposed to bottom out?

i still have some adjustment available,

2. when setting the float level bob suggests 3/4" for modern fuels...is this measured from the gasket mating surface w/ or w/o a gasket present?...i have heard conflicting answers...the only mention i saw, was when he was describing how to correctly set the float drop to 2 3/8"...in that description he merely states from gasket mating surface...
as of right now, i have both set almost perfectly w/o gasket present.

3. fuel inlet needle keeps sticking...at first the float adjustment tab was way off...i thought this might have been the issue, since it was slightly rocking the needle under depression...however, i corrected it when setting float adjustment, as to where it sits almost (95%) perpendicular with needle...
but, the needle is rubber tipped, and that seems to be the reason why it is sticking to the hole...if i gently tap the cap it will free itself and settle back onto the float arm..
is this normal?
could it be because everything is clean and dry right now?
could pressure of fuel flow during operation keep it from sticking?

that is all.....FOR NOW!!!

thanks in advance,
Shant

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Re: rebuilding my 1962 carter yh carburetor... couple questions
Posted by: MattNall ()
Date: February 21, 2012 02:12AM

We'll wait for Steve C Goodman to answer... he's the pro that has built 1,000's most likely after 40 years..





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Somewhere between Sea Mountain and Coos Bay! SW Oregon Coast
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Re: rebuilding my 1962 carter yh carburetor... couple questions
Posted by: jjohnsonjo ()
Date: February 21, 2012 01:49PM

Make sure your idle screw is backed all the way out and choke is totally off before adjust metering rod, the throttle plate must be fully closed. Make sure your gasket stack is at least .300 thick. You often don't get enough gaskets in one kit.Press the rod arm only enough to just touch the lifter link.

3/4" for the float is ususlly good W/O gasket. Use only the float weight, don't press. The float tang MUST touch the needle at exactly at 90 degrees when closed. If it pushes on any angle other than dead straight it will lose seat pressure. Consider a SS ball valve. The ruber tips can be a problem with todays gas.

Float drop isn't that critical, with or without gasket is OK.

Make sure your throttle body ears are flat or the gaskest stack will not seal properly.

Make sure the square block that holds the pump down is dead flat or it won't seal.

J.O.

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Re: rebuilding my 1962 carter yh carburetor... couple questions
Posted by: Boosted60 ()
Date: February 21, 2012 07:03PM

i actually dont have the throttle body on yet...i was assembling it in the order of the book.. (well, i say book, but i mean whats available to view at online store)

since there is no throttle hooked up, id imagine the static adjustment would be equivalent to what you are describing.

but, i have a stack of three gaskets thats exactly .3" for when i do assemble... if im not mistaken, the 62 carb was the one that came with a very thin throttle body gasket...something about a choke rod needing to be bent to adjust correctly after installing a thicker gasket? im leaving the choke for last..

i guess i should also mention, i have a stock 1962 carter metering rod and jet combination...

sounds like my float adjustment is dead on...the best i could get the tang is ~85*.
id say thats pretty dang close...i tinkered with it a bit last night, and moving up and down very straight...the tip still gets caught sometimes, but i think thats just indicative of a good seal...i think fuel pressure during operation will allow it to work correctly...
however, i am interested in the ball valve you speak of, since i have heard that the needle on these carbs can be very finnicky to fuel pressure...

good thing you reminded me...i have to spend some time today straightening the mating flange with a flat file...the ears are pretty bowed in... im measuring .025 deviation with astraight edge and feeler gauge...

by square block, i can only assume you mean for the accelerator pump assy.?
i made sure to check it with a straight edge before assembling...

thanks for your help J.O.
-Shant

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Re: rebuilding my 1962 carter yh carburetor... couple questions
Posted by: jjohnsonjo ()
Date: February 21, 2012 11:33PM

Yep, that's the block. Not sure how wide your straight edge is. I lay it on a "known to be very flat surface" and attempt to shine a light under it. It can be corrected by using the same surace and some wet or dry.

Get a low pressure "Holley" reg and set at 2 to 2.5 psi. The number is already posted.

The thick gasket stack is to help isolate the turbo heat from the fuel bowl.

J.O.

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Re: rebuilding my 1962 carter yh carburetor... couple questions
Posted by: caroseiii ()
Date: February 22, 2012 12:23AM

Don't put as many gaskets as on a 63-66 yh on the throttle body as recommended above because the 62 has shorter screws and unloader link than the later carbs. Replace to same thickness as you removed unless you have longer screws, unloader link and turbocharger stud.
Crawford

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Re: rebuilding my 1962 carter yh carburetor... couple questions
Posted by: Boosted60 ()
Date: February 22, 2012 06:54PM

is the unloader link, the rod and slide mechanism that connects from the back of the throttle shaft to the accelerator pump lifter link?
if so, i need to source one, since it was never there or connected when i got the car...
good to know i need the pieces from a 63-66 style...

im in the process of replacing the majority of the vehicles hardware, so i will get the longer screws and studs as necessary...since i would like to isolate the heat as much as possible from the fuel source...

how come no one makes those high insulating spacers, in the correct thickness for the carb/throttlebody seal? the import guys do it all the time...and its proven to drop intake temps...

you know j.o., i didnt check it as thoroughly as id like to....im going to reinspect it, with your described method...



any insight on the metering rod setting would be very helpful smiling smiley

thanks as always,
-Shant

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Re: rebuilding my 1962 carter yh carburetor... couple questions
Posted by: jjohnsonjo ()
Date: February 22, 2012 11:04PM

Sounds like you are talking about the "the throttle shaft arm connector link" Clarks probably has repro's. Someone in the group probably has one. They can be broken by aggressive adjusting.

The unloader has to do with the choke.

Big disclaimer as I have not tried this YET! While working with my son on his Fiero 4 banger I noticed the gasket under the TBI unit had the same size opening as the YH. It is a composite,3 layer, upper & lower firm gasket with a baklite center. A little work with a band saw and drill press and you have what i believe would work quite well. I have one still sitting on my bench for the next time I need to rebuild the carb. All TBI iron dukes use this gasket.

J.O.

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Re: rebuilding my 1962 carter yh carburetor... couple questions
Posted by: Boosted60 ()
Date: February 23, 2012 06:23PM

how can i go about deleting the factory choke assembly?

will the american pi unit delete all of the choke rod/unloader link connctions you are referring to?

my choke assembly came gutted.. as well as the orifices for the clean air tubes capped ...and the unloader link boss epoxied shut.
when i got the car, to start the engine, i would have to manually close the choke...crank it a few times to get gas flow...go back and open the choke and keep it held open with a spring that was doubling as a throttle return spring...then gas it for a few minutes till it warmed up and i was on my way...

now i know those two things are reverseable...but id like the choke to be as simple as possible...i live in sunny southern california and its never really cold enough to need the choke for that long....

can i cap off the port on the main housing of the carb? the one that travels to the back of the throttle blade (turbo side).
then, once capped.used an electric choke to control the opening and closing of the choke plate only?

any input would be great.

wheres steve?!?! this metering rod situation is driving me nuts!

thanks smiling smiley
-Shant

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Re: rebuilding my 1962 carter yh carburetor... couple questions
Posted by: Boosted60 ()
Date: February 24, 2012 09:58PM

J.O. thanks for the heads up...i put the accelerator pump housing down on my welding table and it was quickly obvious that it was not flat...
took a flat file to it for a few minutes...put a slight bevel on the edges and reinstalled...
looking at that thin diapraghm material...i doubt it would have sealed properly if i did not do so...
thanks for the tip!

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Re: rebuilding my 1962 carter yh carburetor... couple questions
Posted by: jjohnsonjo ()
Date: February 24, 2012 10:41PM

No Problem, Hey Steve runs a shop in Denver so helping out here can cut into business time. He is not on all the time, but it is a great help when he is. Also, just lost his wife, if you follow the posts. The metering rod is pretty straight forward. Please explain again your exact issue..

J.O.

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Re: rebuilding my 1962 carter yh carburetor... couple questions
Posted by: Boosted60 ()
Date: February 25, 2012 12:14AM

believe me...i realize his experience is invaluable...thats why i come seeking his help on the matter...
however, there are also a lot of other competent corvair nuts out there...and i love hearing everyones opinion...thats why i made it a public post so other people who may be in the same boat could benefit from it...

i am not as active as a poster on this site as i once was...so i was unaware of the circumstances...i wish him the best.


ok, the exact issue is this...
in bob helts book he says for a stock metering rod and jet combination you can use the factory carter gauge for setting metering rod height...
i do have factory parts, but not the gauge (which is quite expensive.)

bob says, to use his alternate way of adjusting to deal with any part changes you may encounter...
he makes it quite simple...push down on the accelerator pump rod to mimic engine vacuum... when the metering rod arm just touches the pump lifter link, make sure that the top of the metering rod eyelet, is below the mounting flange...

i have mine adjusted to do so...however, the metering rod is bottoming out at the bottom of its bore at the same time that the metering rod arm touches the lifter link..

im trying to find out if this is ok, or if the metering rod should never bottom out?

i dont want to run into lean condition if i have the rod set too low and it stays on the economy step for too long...

any help is always appreciated..

-Shant

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Re: rebuilding my 1962 carter yh carburetor... couple questions
Posted by: jjohnsonjo ()
Date: February 25, 2012 12:35AM

The top of the rod eyelet should be flush with the top of the body casting (float chamber gasket surface) when the arm just touches the link.

J.O.

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Re: rebuilding my 1962 carter yh carburetor... couple questions
Posted by: steve c goodman ()
Date: February 25, 2012 02:48AM

Sorry, this thread must have escaped me. What JO says is correct about the metering rod height.

I see you are wanting to remove the choke plate, it has been my experience that even in warm/hot etc climates a YH likes to be choked when cold. Typically the accel pump diaphram doesn't work (squirt) that much and fuel doesn't like to go sideways. I would install the choke mechanism and use an electric unit. They work much quicker than the stock heat choke element.

EDIT for this comment: Yes I have been both busy and distracted lately and haven't been following the forum or the P-car sites like normal. You are correct however, there are many very experience folks reading this.

Sincere regards, Steve

1962 spyder 3.0L turbo 1967 monza 110/4
1968 monza 110/4 1971 amante gt 110/4

Golden, Colo. CORSA/RMC/PPCC



Edited 1 time(s). Last edit at 02/25/2012 02:51AM by steve c goodman.

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Re: rebuilding my 1962 carter yh carburetor... couple questions
Posted by: Boosted60 ()
Date: February 26, 2012 02:02AM

hey there steve... hope all is well...i appreciate you taking the time to respond...thanks for stopping by..

ok, well it looks like i need to adjust the metering rod height up slightly still...

i can only now assume that the rod is not supposed to bottom out at the bottom of its bore...

as far as the choke is concerned...i would like to remove the thermo coil and fast idle assembly including heat tubes for choke, yet retain the choke plate itself...

id like to make it as simple as possible..essentially only operating during cold starts..
i believe i understand what you are recommending, and i think we are on the same page...

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Re: rebuilding my 1962 carter yh carburetor... couple questions
Posted by: jjohnsonjo ()
Date: February 26, 2012 02:50AM

If not connected to anything, the rod will bottom out with its top about 1/16" below the gasket surface.

I'm pretty happy with my stock choke. the best thing I ever did was pull the heat line out of the air cleaner and place a small filter on the end. Sucking blow by was the main issue with guming.

Electrics are fine, some even used to use a full manual setup.

J.O.

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Re: rebuilding my 1962 carter yh carburetor... couple questions
Posted by: steve c goodman ()
Date: February 26, 2012 04:37AM

I might have a used mechanical (cable) choke cover. If you decide you want to fool with the long cable let me know. The new cable/housings are lots better than what was on the 1961 production car so IF you use a quality cable/housing you can make the manual choke work ok.

Sincere regards, Steve

1962 spyder 3.0L turbo 1967 monza 110/4
1968 monza 110/4 1971 amante gt 110/4

Golden, Colo. CORSA/RMC/PPCC

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Re: rebuilding my 1962 carter yh carburetor... couple questions
Posted by: Boosted60 ()
Date: February 27, 2012 01:55AM

looks like i need to raise the metering rod height slightly...
my logic behind it is this...
if the metering rod is bottoming out in its bore at the same time the metering rod arm touches the pump lifter link, it is approximately 1/16" lower than the gasket mating surface..
if the top of the metering rod needs to be almost flush with the gasket mating surface, it appears i need to adjust the metering rod height roughly 1'16" up...

this sound about right?
i just want to make sure i have it set correctly, as i dont know what ill effects an improperly set metering rod height will cause other than a lean condition transitioning into throttle...

as far a manual choke, id like to keep that as a final resort...
id like a simple electric one that merely controls the opening and closing of the plate...
i would try to make the stock setup work, but i am missing all the pieces and dont want to go through the trouble of finding them and making it work...i believe electric is the best option for me at this point...

if im not mistaken, the fast idle port only has two orifices...one on the side of the carburetor(beneath choke plate) and one behind the throttle plate(turbo side)...
would blocking the port in the throttle body be the best option? since it would inhibit any vacuum leaks that may occur between the carb and throttle body...

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