Elton Ace Carb bubbling

[tom-c]

Why is this happening?

https://youtu.be/1KNJrOsQ2Gk

[legendre]

If I had to guess, from what I see..

The carb is flooding, and fuel is being pushed out of the top vent whenever the intake manifold pressure rises above atmospheric.

If you’ve ever been able to carefully observe the intake on a running engine, you’ll sometimes notice that fuel charges are repeatedly ejected from the carb mouth and then abruptly sucked back in, as the cycle progresses. This is the result of pressure in the intake rising above atmospheric during a cycle.

If the fuel level in the bowl is too high, I can see a situation where the pressure pushes fuel right out of the carb vent.. as the same pressure that bears on the intake also bears on the fuel in the bowl, via the main jet (and possibly other passages).

[tom-c]

I recoated the cork float. maybe I didn’t position it down far enough?

[legendre]

quote Tom C:

I recoated the cork float. maybe I didn’t position it down far enough?

Anything that influences the carb float height can cause fuel level issues. I have no direct experience with the carb you’re working on, but they all have one thing in common – there is a relatively tight range for correct fuel level. By ‘tight’, I mean within +/- 1/16" for a small carb like this.

Also, I have no idea what condition your float was in prior to re-coating. If it had absorbed fuel, it’s still going to be heavier than spec, and as such, setting the fuel level too high. If you can easily adjust the float to a lower level, do it – move it by 1/16" or so, and see if it changes the behavior.

BTW, how does the motor run otherwise? Is it rich, lean or seem to be A-OK?

[ggoldy]

What year Ace do you have? I’ll see if I have a carb parts breakdown. Although Garry will probably beat me to it LOL

[kevinf]

The Ace has a valve lift of 1/8" and and the fuel level is 23/32" from the top of the bowl to the gas level if that helps

Kev

[The Boat House]

• This reply was modified 6 years ago by The Boat House.
• This reply was modified 3 years, 9 months ago by The Boat House.

[tom-c]

Thanks very much! I’ll get to this in the next few days since I have out of town visitors and a very busy family weekend! I hate it when I have to mess up my priorities! 😉

[legendre]

@Tubs

Does the float valve pin on this carb lack a locating groove for the retainer clip, as found on others such as Johnson TD/HD carbs?

Can the float be set at an arbitrary position on the pin, varying the fuel level, such as when one bends the float arm on an automotive carb?

[garry-in-michigan]

Yes, there should be more of the float pin showing.

[Author]

Posts