67 slant with 1920 holley dies when engine heats up and choke opens.

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71twister3bytheknee6

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Hello,I have the above problem.Engine runs perfect until choke opens.I have replaced the fuel pump,and fuel filter.Engine is perfectly tuned,new points plugs,valve lash,timing adjusted.I have not found any vacuum leaks.I am not knowledgable about carbs.My next step,unless somebody has other tips,will be to install a refurbished carb I have had in storage for a couple of years,just for this scenario.It is a direct replacement,outside of one extra threaded hole intake near the needle adjustment.I just plugged it up with a bolt.Any suggestions would be greatly appreciated. Thanks,Rich
 
Carburetor operation and repair manuals and links to training movies and carb repair/modification threads are posted here for free download.

That "extra threaded hole" on your replacement carb means it is a '69 unit (unless it made a voyage down from Canada, where the '69-only-in-USA throttle plate anti-ice system was available starting in '61). The carb is calibrated for that air inlet at the throttle base to be open and flowing; it's best if it's routed via a screw-in hose nipple to the clean side of the air cleaner, but that might be more work than you're up for.
 
Slantsixdan,Thanks for responding.I took the old carb off,examined it,and where the fuel line flair inserts into the carb,I found two small pieces of rubber,I believe,no doubt starving the carb.I did this,though,after I put a refurbished carb back on the car.It runs allright,heh,better than the horror stories I have been hearing about refurbished carbs.But I am thinking of putting the old carb back on,though,Monday,Labor Day.Where the fuel enters the carb,there appears to be a black rubber membrane behind the small (about 1/8 inch) round opening to the carb.The small area I see seems fine.Could any of the small pieces of rubber I found have worked there way in a reverse direction,meaning there is damage to something in the carb? Or more likely to me,the rubber pieces came from the 2 fuel filter hose edges,maybe,and got hung up right before entering the carb fuel inlet. Rich
 
71twister3bytheknee6 said:
where the fuel line flair inserts into the carb,I found two small pieces of rubber,I believe,no doubt starving the carb.
Click to expand...

Trash pretty much anywhere in the fuel system is going to make problems. The closer it gets to the heart of the carburetor, the more problems it makes. However, it is very unlikely that trash in the location you mention would cause the problem you describe. If it were blocking the flow of fuel, the engine wouldn't run even with the choke closed. I think the carburetor exhibiting that behaviour has some clogged internal passages that need to be cleaned out.

It runs allright,heh,better than the horror stories I have been hearing about refurbished carbs
Click to expand...

There's nothing wrong with a properly refurbished carburetor. "Remanufactured" carburetors (and other parts) tend to be junk.

Where the fuel enters the carb,there appears to be a black rubber membrane behind the small (about 1/8 inch) round opening to the carb.
Click to expand...

Yes, that's the rubber tip of the inlet needle. It's supposed to be there.

Could any of the small pieces of rubber I found have worked there way in a reverse direction,meaning there is damage to something in the carb?
Click to expand...

Probably not.
 
slantsixdan said:
Trash pretty much anywhere in the fuel system is going to make problems. The closer it gets to the heart of the carburetor, the more problems it makes. However, it is very unlikely that trash in the location you mention would cause the problem you describe. If it were blocking the flow of fuel, the engine wouldn't run even with the choke closed. I think the carburetor exhibiting that behaviour has some clogged internal passages that need to be cleaned out.



There's nothing wrong with a properly refurbished carburetor. "Remanufactured" carburetors (and other parts) tend to be junk.



Yes, that's the rubber tip of the inlet needle. It's supposed to be there.



Probably not.
Click to expand...
 
The remanufactured holley 1920 carb...not so much:bogging down for some reason (possibly due to the one extra vacuum hole for anti-icing I had,which I plugged.But I also left it unplugged,and drove the car,filling it up with a little bit of cotton cloth for a temporary fix so it could breath,and the car ran,but not any better,or worse.Remanufactured carbs are now suspect in my book.I decided to clean and rebuild my old carb,and I have no experience with carbs.I understand the Venturi principle,but that is it.I did first put it on the car without rebuilding it (I had only cleaned the needle and seat assembly),but the cleaning,as Slantsixdan thought,didn't help it any.Well,I feel like a NASA engineer who had worked on the Lunar Rover,the car runs great,like it did before.After disassembly,I sprayed every orifice I could find with carb cleaner(next time I will invest in the soaking solution with pail you can buy).I then followed by boiling in water,but keeping one pivoting plastic piece on the main well and economizer assembly out of the water not to damage it.I could have removed it,but didn't want to take a chance cracking a probably near 50 year old part.I have no compressed air,so I put the carb in a warm,dry oven to dry it out.The carb kit and illustrations were great,and I took pictures prior.I am thinking of cleaning and rebuilding the remanufactured carb now.YAH BABY,GET YOURSELF SOME OF THAT,R. Rawlings,A. Kaufman,D. Short,E. China,and Slantsixdan (they would be keeping good company with you, Slantsixdan).I'm stoked that I have my car back,instead of a 2,750 pound,$10,000 paperweight. Rich
 
My slant is running great with the old,original carb I refurbished myself.I wanted to see if anything was amiss with the remanufactured one I have,which ran on this slant,but was bogging down on acceleration.Low and behold,I have a 50 jet size in it,and the Holley list #4165 states it is a 1969 carb,and should have a 56 for auto,57 for manual trans.If the jet numbers are linear,6 divided by 56 is almost an 11% loss.Do you think that could cause bogging? Rich
 
"Bogging" has a specific meaning; I think you mean you're experiencing hesitation. And yes, a № 50 is too small.
 
Thanks,SSD.Yes,I do mean hesitation on acceleration.By the way,this slant I have been talking about is a 225 CID,1967,manual transmission.I noticed that some 198s used a 50 jet. Thanks for being so helpful. Rich
 
Hesitation on acceleration, though, likely isn't because of a too-small jet. That's usually more to do with the accelerator pump producing an insufficient shot, either because it is faulty or because it is not adjusted correctly.
 
You should set the timing curve for your engine to eliminate the possibility of incorrect timing contributing to your problem.

If you floor the car from a dead stop and it hesitates, it can most certainly be because of a jet that s too small.
 
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