Holley carb help

[soyen]

I have a Holley Carb that has list-1850-3 and the # 2111 stamped under that. after it warms up I have issues with it cutting out and rendering it un-drivable. I can normally wait until it cools down and will be able to drive it again. the issue Is with the fuel delivery. I know it's fuel because when I look down the horn I can see the fuel stop pumping into the throttle body when it starts to cut out...

I've owned it for about 2 months and have replaced the fuel sender, cleaned the tank replaced the fuel line, the fuel tank switcher ( from manual to 12V off the Tank toggle), fuel filter, and now the fuel pump. I went through the float adjustment on Holley's website and adjusted the fuel in the bowls so it is just barley trickling out of the windows like it said to. I figured I had to be getting close, so in a last ditch effort I pulled the vacuum hose off between the carb and distributer and plugged both. everything seemed to clean up and I was able to drive it up the block and back. ( Im a little gun shy about getting to far away) .

My questions:
1) Is that vacuum line necessary?
2) I'm guessing that has something to do with Timing?
3) was my problem the timing all along?

 

[tbrend]

Do you know if it is a non-adjustable float model? 4160?

 

[bronconut73]

Could it be vapor lock?

 

[jckkys]

The list 1850 model is a 4160. My 1958 Merc with a 430 had one from the factory. The only thing that's changed in 56 yrs. is the Chevy throttle lever and Ford kick down for C6s and C4s. They all have externally adjustable floats. All floats are adjustable even the the newer Holleys that have to be adjusted by removing the float bowl.
Is your carb equipped with an automatic choke? Is the engine dying when the choke opens and the throttle closes to the curb idle screw? Have you tried increasing the curb idle speed or adjusting the idle mixture when the engine starts to "cut out"?
The vacuum advance hose shouldn't change anything at idle. You do want to put it back on for driving once this problem is fixed. You won't see fuel in the booster venturis at idle. The engine gets all the fuel it needs from the idle hole and transfer slot below the throttle plates.

 

[jckkys]

The list 1850 model is a 4160. My 1958 Merc with a 430 had one from the factory. The only thing that's changed in 56 yrs. is the Chevy throttle lever and Ford kick down for C6s and C4s. They all have externally adjustable floats. All floats are adjustable even the the newer Holleys that have to be adjusted by removing the float bowl.
Is your carb equipped with an automatic choke? Is the engine dying when the choke opens and the throttle closes to the curb idle screw? Have you tried increasing the curb idle speed or adjusting the idle mixture when the engine starts to "cut out"?
The vacuum advance hose shouldn't change anything at idle. You do want to put it back on for driving once this problem is fixed. You won't see fuel in the booster venturis at idle. The engine gets all the fuel it needs from the idle hole and transfer slot below the throttle plates.

 

[broncnaz]

Welcome
It sounds like you may have had your vaccum advance hooked to manifold vacuum which resulted in to much timing. You should have the vacuum line connected to the vacuum port near the front fuel level window. Not the one under the front of the carb.
Also if you have a dual port vacuum cannsiter on your distributer you only need to hook it to the front port. The rear port retards timing.
Might help to have some more info on your bronco like what year? what ignition? and Any issues you have now.

All the 1850's sold now are universal carbs with manual chokes.

 

[soyen]

The bronco is a 1969 not real sure about the distributer I've added some I always take pictures before I tinker ill try to get some pics on here
. oh also a manual choke. the choke was plastic and broke and melted so I ordered a replacement manual choke for it as well. according to your post broncoaz I had the vacuum on the correct port.. apparently I'm not smart enough to get the pictures uploaded to this forum.. I'll work on it after I get home tonight
.

 

[PaveBronco]

X2 on the Vapor Lock...or a tank issue, cap not letting air in, maybe try remove the gas cap and see if it drives the same, or just replace it...

 

[SHX669]

Or crud in the gas tank plugging up the intake tube. I've read about all kinds of stuff people have found in their gas tanks.
SHx

 

[tbrend]

X2 on the Vapor Lock... or just replace it...

http://classicbroncos.com/forums/showthread.php?t=241118

 

[pcf_mark]

I have not had vapor lock on a Bronco but on GM cars it can be a pain. Easiest check is let is get good and hot while driving then shut it down with the hood closed. After a few minutes (3-5) it will have really heat soaked. Open the hood and see if fuel is dripping out the boosters (round things down in each throttle bore in the carb). If it is really going you can see the waves of smoke coming out. The carb is heating up from engine heat and the fuel gets hot, expands, then flows out into the carb drowning the engine. Holley makes a nice little metal shield that goes under the carb that cures it. If your fuel lines are routed too close to the headers you need to wrap them too.

 

[soyen]

I've pulled both tanks and cleaned them just got a new fuel sender from TBP today for the rear tank I'll be putting that back together tonight. the Aux tank is plastic so there wasn't any issue with crud in that one. I'll try the gas cap trick tonight. the only thing I haven't done is take the carb off and try to clean it. I can't find the pictures or albums location on this forum to drop pics on this thread... is that a paid member option or something? IDK. so I uploaded some pics of the Carb and Distributer to my profile.

 

[soyen]

 

[soyen]

Ok I've posted some pics in my Gallery there is a link on the left hand under how many posts I have on this forum

 

[broncnaz]

Dist tag indicates its a 1984 so its probably been converted to electronic. ie factory duraspark.
Vaccum advance is not nessesary but it does help. It really shouldnt be causing your issue. You say it starts cutting out then when it cools down you can drive it again. Id kinda suspect the ignition module may be going bad. They act like that when they go bad.
Of course check the fuel system things that were mentioned first as those are practically free to check. I think some parts stores may be able to check your ignition module.

 

[tbrend]

You can also put on a clear fuel filter. Check if there is any gunk.

 

[jckkys]

The plastic manual choke is new to me and I have 3 or 4 1850s. Two of them have automatic chokes. The 1850 was Holley's first 600 cfm in 1958. The 1957 4bbl was a 390 cfm. The 1850 became the lowest price 4 bbl and as time passed they cut pennies everywhere they could. Both the manual chokes you show in your photos are left with the cable detached. Do you use the choke or leave it open for cold starts?
The early Duraspark transistor modules were known to malfunction when they got hot and cause the engine to die. When things cooled down they would work until they got hot again. In these cases the engine didn't start running poorly. It just died. A new or junk yard module could tell you if that's the problem. You want the one with the blue strain relief.

 

[soyen]

ok so after about the 3rd time my mechanic uncle canceled on me(The uncle with a timing light)I finally went out and bought a timing light. the Timing was set on the 26th mark and with the vacume attached it would go off the chart when I reved up the engine. I dialed it back to 12 at Idle and it seems to run better. what is the magic # everyone is running for timing at I've read between 10 and 14 at idle depending on how cold it is.. and I idle at around 700 to 800 rpm. feels good to get it figured out, but that was a lot of troubleshooting in the wrong direction.

 

[soyen]

oh and as far as the choke cable I'm '"in between choke cables" original one was broke and I was going to order one as soon as I got this issue fumbled through.. Thanks for all your help!

 

[broncnaz]

10-12 degrees tends to be a good spot for many engines. You kinda have to test whats best for your engine.



jckkys

The plastic manual choke is new to me and I have 3 or 4 1850s

Well step on up to at least the 1980's and the 1850 became a universal carb with a manual choke there was no electric choke option unless you bought a seperate kit. Now there are -1-2and -3 versions maybe more which most of the later ones have the plastic choke and secondary covers.
Highly doubtful that jetting was even the same. between there 1958 vintage and todays 1850. basic carb is the same but thats about it. Looking around and almost all the 1850's you will find are the universal ones you have to really look for a vintage one.