fuel level and performance

[Posi]

I've set the timing to 12 degrees with a light. I just got a vacuum gauge and will check that today. Is there a better place to attach the vacuum gauge to get the best reading?

Factory is 5*, ok range is 3*-7*
Full vacuum port on the intake.

 

[thistle3585]

I just completed the vacuum test. It held steady at 19. Dropped to zero when reved then came up to about 23 then back to 19.

Yes, I plugged the vacuum line when I set the timing. I'll recheck it. I remember it being two tick marks back, so it may be 7 not 12.

It has been sitting on an incline, nose up, and it has been running/idling no problem. On level ground, it goes back to being more erratic. I'm still thinking its a fuel level issue in the bowl. I am going to put the float from my old carb on it and see if that allows me to set it so the fuel level is higher. Why does the fuel level in the bowl affect it if the level doesn't ever go below the jet height where it would be sucking air?

 

[Lumpy Grits]

Does your fuel filter have the 2 outlets?
The larger goes to the carb.
The smaller is a return line and MUST be at the 12 o'clock postion.
LG

 

[thistle3585]

No return on fuel filter.

 

[Fastatv]

I just completed the vacuum test. It held steady at 19. Dropped to zero when reved then came up to about 23 then back to 19.

Yes, I plugged the vacuum line when I set the timing. I'll recheck it. I remember it being two tick marks back, so it may be 7 not 12.

It has been sitting on an incline, nose up, and it has been running/idling no problem. On level ground, it goes back to being more erratic. I'm still thinking its a fuel level issue in the bowl. I am going to put the float from my old carb on it and see if that allows me to set it so the fuel level is higher. Why does the fuel level in the bowl affect it if the level doesn't ever go below the jet height where it would be sucking air?

This post pretty much tells me that the problem is associated with the carb. As I mentioned before, my carb problem seemed identical to your....including idling fine on an incline. I had said earlier that a cleaning and rebuild eliminated the issue I had, however, I failed to mention that my carb base gaskets were a mess, and looked as tho they could have created vacuum leaks. Along with rebuilding the carb, and cleaning and installing new base gaskets, the problem went away...and has stayed away for about two years now. I hope this helps in some way. And good luck...keep us posted.

 

[thistle3585]

It was a fitting in my manifold that had been capped. I was using it to do the vacuum test which is why I couldn't find the leak. It leaked with the cap but the vacuum testing hose sealed the leak. Still having issues with the fuel level float but the it is performing much better. I need to go back and retune the carb and see where I stand after that.

 

[Lumpy Grits]

It was a fitting in my manifold that had been capped. I was using it to do the vacuum test which is why I couldn't find the leak. It leaked with the cap but the vacuum testing hose sealed the leak. Still having issues with the fuel level float but the it is performing much better. I need to go back and retune the carb and see where I stand after that.

BTDT-
Get some of those little thin tie-wraps, use them on every dang vacuum fitting you can find.
LG