Hello everyone,

I rebuilt my carb last week and threw it on the 6 cylinder 223. Truck fires right up and I tuned the fuel/idle screw with with a vacuum gauge. Set timing 4deg BTDC using a timing light. Truck idles great and has power in all gears.

Weird thing is the truck will bog whenever I make any long sweeping left turn like crossing and intersection. As soon as I straighten out however engine speed picks up and im back to the races.

Any suggestions would be helpful. Thanks

 

How was the float when you rebuilt the carb?

 

Its a brass float that didnt have any visible punctures or dents. I threw it in the the can of parts cleaner and it was floating with no air bubbles. When installing it I read the best way to set the float level is turning the carb upside down and make sure the top of the float is exactly parallel with the edge of the float bowl. Is that correct?

Im visualizing the fuel sloshing to one side of the carb bowl. Taking a left turn would move fuel away from the acceleration circuit. I cant for see the fuel moving so much that it wouldnt be getting enough fuel though.

 

If set too high, could it flood a little in a turn? Or dies it sound like it is running out of gas? Does it do it in an empty parking lot if you turn slowly?

 

Havent tried doing donuts in the parking lot yet. If I swerve in an open street itll have some hesitation the moment I swerve a little to the left.

Not really sure the difference in feeling of when engine runs out of gas or floods.

 

Either way I think it has to be a float adjustment issue.

 

Without being there in person, say it’s flooding. Dollars to donuts says it’s a flood problem

 

You can recheck the float level and lower the fuel level slightly. If you run out of fuel on a hard pull, then you know its too low!

Kinda strange its only left turn. I had a similar issue but was a wire shorting out when the harness shifted on acceleration randomly. Just another possibility.

BMC

 

Thanks for the replies. Going to try to bend the float bowl down and see how it reacts.

 

Float height is just a bench setting, to get it reasonably close. The shop manual or carb manual will have a fuel height specification somewhere in thar, sometimes called "wet height" - after a carburetor is actually installed on the engine. This is what really counts, because the carburetor is calibrated from the factory for a certain level of fuel or column height in the bowl and air bleeds &c for siphoning action. Ever notice how much easier it is to get a siphon started from a full gas tank than one that's half empty? Adjust the float up or down as required to achieve the fuel height specification once its on the engine.

The engine does not need to be running to do this.

Anyhoo - for a lasting repair to begin with first make sure the carburetor is getting both the correct pressure and volume output from the fuel pump.

Let the engine idle for a few seconds and direct the pump output into a clean container. At least a pint in 30 seconds would be reasonable. Check static pressure output using a mechanic's vacuum gauge, they all will test mechanical fuel pumps. 4 to 5 psi. is plenty, more is definitely not better. Excessive fuel pump output on new manufacture replacement pumps is kind of a thing now. Nobody hardly used to check fuel pump pressure, probably because it wasn't often a problem. Well, it is now.

 

Worked on the truck a bit today. Bent the tab up, down, and what I thought was where I had it. Truck is still doing the same thing however it is now flooding out of the weep hole at the top of the carb after idling more than 5 minutes.

I will try cranking the engine over and see what the flow rate is of the pump. I feel that isnt the issue since truck was running just fine going straight and doing right turns. I checked the static fuel pressure before I rebuilt the carb. 5 psi. Ill check it again tomorrow for the heck of it.

I have a spare universal 1904 carb thats brand new. Havent tried running it before.

 

Well there will be an actual fuel height (not float height) aka "wet height" spec in the shop manual, within 1/32", the idea is to move the float up or down by bending the tab as required to achieve this. I like to remove the float when doing this, so as not to maybe damage the viton needle & seat. Check the parts diagram carefully too, make sure all the parts are installed, all the little springs, checkballs, gee-gaws and fiddly bits. Some aren't reproduced and or aren't necessarily included in the rebuild kits. For some reason rebuilders like to throw stuff away. If a part is included, the OEM really thought it was necessary, or they would have eliminated it and saved .50c

Different carburetors have different ways of wet height adjustment, when the carb is actually installed on the engine, some easier than others. Holley of course has their patented jamnut & screw, allowing for fuel height adjustment on the fly while engine is idling, till it just reaches the weep hole. The Autolite 2100/2150 series can be idled with the air horn removed and fuel height observed if necessary.

If the float height or fuel height is off significantly from spec it will be either starved for fuel at high speeds or hard acceleration, or tend towards flooding out if extreme. The plugs would likely be at least a bit fouled if it was the latter. If ignition and carb and everything is tuned well spark plugs should be very clean burning with modern gasoline.

 

Thanks for the lengthy reply. This a 1904 Holley which doesn’t have any wet height adjustment it seems. I think other holleys have an adjustment screw on the bowl. There is no fuel height check hole either unfortunately to see if the fuel is indeed too high. Really wish I had a glass bowl to see what’s going on.

i bought my rebuild kit from mikes which seemed pretty comprehensive. I tried cranking the motor with the bowl cover off while holding the float up to see if it would seal the needle and it did. However this isn’t an accurate test since manually holding the float up is providing more force than it would see from the buoyant force.

 

I can't be of any help. I fought this issue with 2 different Holley 1904 and finally gave up, but mine do it on really sharp Right turns.
There is a wet fuel level spec, I don't recall what it is. You have to remove the little 3 screw cover on top that holds the diaphram/shaft with spring for the power valve and measure from the top of the carb body to the top of the fuel level. I have a glass bowl model and have moved the float level up and down a little but that never changed anything. If you have gas coming out of the top thats a problem. Years ago I read on off road jeeps using 1904s also had issues.
Is the new carb you purchased one of the cheap Chines repops that are on Ebay all the time?

 

That’s a bummer to hear hiball. What did you end up doing to the motor? Just driving as is? I got the spare universal carb from mikes carburetor.

https://www.carburetor-parts.com/190...ew_p_3141.html

https://www.carburetor-parts.com/***...RB_BOOKLET.pdf

there isn’t very much information online But the company Daytona appears be reputable.

ill slap it on and see how it goes. I kind of wish I didn’t mess with anything in the old carb as it wasn’t flooding before at idle.

I’ll keep tinkering and post if anything new comes up. I was hoping to have this thing running decent so I could take pictures with it on my wedding day. I have a spare 289 engine that I may need to figure out how to drop in now. Didn’t want it to come to that.