Carb series ? help

Well as usual for me I have another issue that most don't run up against. My BB will stall at idle after driving a few miles.(not all the time and idle RPM makes no difference) Cleaned out no visible dirt in the carb..all adjustments are good but found that when spraying the throttle shaft with cleaner, the idle will drop (actually sounds better) then goes back to set speed. Also the shaft was loose. Issue is the carb is VERY old and I see Holley stamped on the front but there are no numbers anywhere on it like "4510"..or date stamps. Can anyone, by looking, identify the series it is so I can order a new throttle shaft. Thanks in advance to all. Thanks MOPARTS

Did this problem just start on an existing combination?
Is it an auto or stick?
If an auto have you tried slipping it into neutral when coming to a stop
Another issue that will commonly cause this is the mechanical advance being set too loose (IE: coming in at or just of idle)

When you say RPM makes no difference does that mean it will die even at 1500 RPM?
Might also have a stiffened power valve which they will do over time.
A bit a leakage around the throttle shafts is normal (to a point). The hsafts normally don't wear but rather the baseplate itself.

I would start by verifying the mechanical advance is not coming in to soon. might also want to check the vacuum advance as well if your running it

looks like an early custom made, ut the choke tower off and other mods,.
That looks like a early double pumper body
Measure the throttle bores and plates and post those on here so maybe SOMEONE can look them up in Holley on line spec charts

It's intermittent as it runs down the road fine...no change in performance..IF you rev the motor at a light a bit constantly, it wont't stall. 8 ot of 10 times it quits without warning..other 20% it seems to load up and then die. It does not give any problems ever when warming up. Only after running a medium to large distance and then quits after like idling down to find a parking space or waiting at a light. Temp gauge is always around 185 to 190 when it stalls. And again, it is not every time....just always at a bad time...lol
it's definetely a holley dual feed double pump of some model series as I need to know what series it is because I'll either get a new base plate or buy a new carb

It's an automatic and once had it idling at 1000 rpm and it died. Reving in neutral and it won't die.

Mechanical advance.

Problem just started a few weeks ago

Have you cleaned up the advance weights? Maybe they sticking just enough to effect low engine speed. Timing could be dropping too much in gear. It looks like an old 4150. Start the engine a blow some air thru the idle bleeds, see if that helps it also. Also sounds like a vacuum leak at base of carb. Might be causing to go lean at idle after it warms up.

How do you get it home? How do you get it restarted?

Vapor lock?

Drive it home starts right up...Don't believe a vapor lock issue.
Blew air throughout the entire carb..including bleders. Ran gumout directly while running...disassembled carb next day and cleaned...aired...was no visible dirt
evidence of a leak at throttle shaft as with spraying there the idle gets lower but doesn't stall. BUT.. one person said some leakage is normal there...but what is the normal amount of "some" lol. I'm going to change the entire base plate assembly Monday. A friend has a spare "parts" carb. I bought the carb years ago from a friend and it's been fine until now. My friend bought it new in 1995 so I guess an issue is to be expected after 27 years.

Possible Ign.problem coil heating up ?

Would not start up so easy after stalling I think..plus it's not all the time and if it stutters before stalling and I throttle up...it won't stall

Or a flaky ballast? One on its way out can cause your exact symptom. A cheap try
Have you checked your Voltages ? You may have a voltage drop that is wreaking havoc on the ignition by not providing adequate V at idle. Increasing the RPM bumps the available V up and avoids the stalling

had it at 1000 rpm in drive and it was 1300 in park...still stalled

I agree on what it looks like.

What ignition system? Sounds like when an ecu has a bad ground. Gets worse when hot. Something like a petronix will get wonky when it’s hot wire sees lower voltage when under hood temps go up. Looks like you don’t have a voltage reg hooked up. Running a one wire? Is it charging good at low rpm?

electronic orange box ignition. Internal voltage reg in alternator..(108 amp) Charges normally Haven't seen any carbs of this type with a choke tower

look for a list #,That will tell you what carb it is, The throttle shaft is steel and the body is cast aluminum so if anything is work it will be the body not thge shaft. You will have to have it machined for bushings to fix it.


Not sure where they put them on the larger carbs but the list below might help some.

https://documents.holley.com/techlibrary_carb_numerical_listing.pdf

Check your voltage at the battery terminal on the alt. and battery POST not cable Should be within .2-.5 V at worst.
Then check V going into the ballast at idle. Should be about the same as the battery and Alt.

You can also see if it V increases with RPM.

try a ballast. They are cheap and can cause these symptoms when getting ready to fail

Also as SCG said VERIFY the ground on the ECU. Ideally it should be grounded directly to bare metal on the ECU & motor

Just for grins I ground all the paint off both sides of the box and ground off the paint on the fender. Also installed a new ballast resistor. AND of couse it's raining out so I have to wait for it to stop to do a check ride. Before doing all that I did check continuity of the box to ground and it was a direct short.

just an FYI: you can measure 0 ohms resistance but the connections ability to handle Current is another thing all together.

Grounds can also sometimes be intermittent and a challenge to identify. Increasing the engines RPM may raise the alternators V and current (I) output enough to mask a bad connection or ground. A small wire braid ground strap between the motor and control box is ideal.
Also I have seen more than one ballast that is on it's way out cause issues like your experiencing. The resistor is breaking down internally resulting in the issue occurring. Again raising the RPM may provide enough current to "bridge" the internal resistance. Measuring them when cold may show good Ohms wise, but hot may be another reading keep us posted

Box is grounded for sure...new resistor.....same result....more of a fuel issue I believe as it started to stall and I caught it twice by playing with the gas peddle. Seems to be loading up at idle...today I am changing the base plate as there is a leak there that noticeably affected idle. To be continued...looking at throttle shaft as that a week or so ago I noticed the shaft was very loose and tapped it beck into place..the issue of stalling was before and after tapping the shaft back in. Pretty solid but I sprayed the shaft with gumout and the idle dropped noticeably and then came back up as the liquid vaporized.

Bummer, problems like this can be challenging to diagnose I'm assuming you are getting good response from the mixture screws when adjusting them ? if so that would indicate the idle circuit is doing it's job and functioning as well as compensating for the suspected shaft leak.

I just had another thought When idling, have you tried SLOWLY restricting the air into primary side of the carb? Think of very slowly closing a door. IF you get to a point in which the idle picks up / smooths out it indicates a small vacuum leak that is otherwise not noticeable,
i had one years ago that drove me nuts for a quite a bit, I finally just checked & tightened the intake bolts,
MAGICALLY all was well
Keep us posted

the throttle shaft was loose when getting to the shop. 23 mile run. Took the carb off and put a race base plate on it (only thing available) and the carb ran at 2000rpm and stalled at 1800. definetely not good. looked at the original base after about an hour and the throttle shaft was solid as concrete. Explains why it stalls after getting to temp. The race base wouldn't work so I have the original back on to get home. Looking to get a new carb as why throw money into parts for a 27 year old carb that has seen better days

They make bushing kits for the throttle shafts......I've never done one but it might be worth a shot if the carb otherwise works the way you like:

https://www.google.com/search?q=hol...86j0j15&sourceid=chrome&ie=UTF-8

All things that ran good at one time can be fix to run good again, the hard part is figuring out what wore out or went bad to cause the repair issue
You can fix it, don't GIVE UP You can fix it

The Quick Fuel Brawler carbs are nice for the money. The only thing bad is the IFR is in the top position and the T slot needs restrictors. Everything else is tuneable even the pvcr is threaded with small jets.

Saw that but why waste time and money on a 27 year old carb...Thx

Thanks Coach but I'm tossing in the towel on this one....lol

Installed new proform 850 ...tuned and is ok now. Thanks moparts...thanks to all who contributed

Well...the new carb didn't fix the problem.

I believe I finally found the problem. My alternator belt always was not real tight but I had no problems with the battery charging enough to keep it starting with no problems. So a friend said that possibly at idle the alternator is not putting out enough to support the ECU and it cuts out at idle. This would confirm why it never did during warmup(higher idle) or when in neutral at a high idle. So I start to pull the alternator and get it loose and turn to get a tool off the bench and when turning around I see the interior of My car is full of smoke. Alot . So I now disconnect the battery and see the GM 108 amp alt slid down and grounded the hot wire to My block.

I remove the alt...get it checked and it checks ok. I change the half ass mounting bracket for the alt and install it and get a very tight belt. After changing a few wires under the dash and installing a new amp gauge,the car fires up..(starts) and I take it out for a long run and no stalling at any light. Been out a few times and no stalling. So I assume the belt was not tight enough to supply a good charge at idle and that caused the ECU to quit.

All of this...new carb...fuel pump...fuel filter...for naught. But replacing that 27 year old carb with a new Proform seems like I picked up a bunch of more power. Like that's needed with a 472 Hemi.

I posted this because IF someone has a similar problem...this is something to check. I got a lot of responses to this problem, and I appreciate all and MOPARTS for the help.

I'm a bit confused as the OP was "terzmo". You are now saying a loose alternator belt was the cause. That also doesn't make sense as the car should have kept running off the battery

I lost My password as TERZMO and got frustrated trying to log in so I started another account under My alternate email. I contacted the administrators but got no where with that. The belt was not right as far as tension...tightening it and I have had no problems with stalling since. Been out 4 to 5 times...sat at lights..idled through parking lots trying to get it to act up and it hasn't. It stalled after warming up during all the conditions just noted. I should of checked alt output at idle before tightening but didn't Now at idle , at the battery. It see 14.1 volts. That's all I did after changing fuel pump..fuel filter and filter placement and carb.

OK...I'm back as terzmo and Checker is temporarily sidelined. Thanks again for all the input

"That also doesn't make sense as the car should have kept running off the battery "confused shruggy I can only assume by interrupting the voltage or running a negitive charge because of loose belt, the ECU would shut down at idle speed.( I have seen meters go to the negitive side at low idles) Electronics have an operating input and output threshold . All's I know is after doing all the other changes, nothing fixed it. Even by shorting the alt and burning wires, the alt checked good at a long time experienced electric shop. ( I was shocked it checked good and still putting out 108 amp-s plus) I have taken the car out about 5 times on decent rides and it has yet to quit.

Strange??? Welcome to the world electronics. one would have to have a complete accurate schematic to figure this one out as in theory it should have run off the battery unless it was too low. But then it wouldn't have started again. Almost sounds like the ignition is getting it's power from the Alt. thanks for the feedback

1955 work as well ?
https://www.ebay.com/itm/115491061377?hash=item1ae3cdbe81:g:FHwAAOSwNNli9E3t&amdata=enc%3AAQAHAAAAsKk1sDtPwSGytc%2F76Kq0P4RzO9xPwi03NWCaOzvGf6Ho%2Fka7Ud8vyX2%2B8LOsjWNDkWXp6VVNLiCqyteYoPKwIZ3c0OGyW2UZ6i36BccALXZ0FE0Ck8qjunEvpE3V%2FdiIrRrMJOgh7Y2yJlS5evQBShDkVUcCnThHlHDodOF%2BqRJSmHAUERgCtH9H1xmH1v5tIJcIqw%2BMtZHRChTQpmA4O8vuNw6mcK6%2F%2BNVHJMh%2FO7Fs%7Ctkp%3ABk9SR-Dc1pnzYA

another one listed on same page but scroll down further

https://www.ebay.com/itm/115491061377?

this better ?


well, no, it ain't.............
that link is to a ferd truck [?] script badge.......

Why does this Mopar Hemiroid motor not look like a BB Mopar?
Probably because it is not BB