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Wouldn't Start, Now Starts but Revs to 6000+

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Activating the choke on a DCOE allows air/fuel mix in thru a separate circuit with BIG holes behind the throttle plates. The plates/shaft don't move with choke. But it appears from the pix the cable is attached and choke is shut. Tho I have seen the tines of the choke piston actuators break and allow the pistons to rise on their own. Many factors involved here, trying to narrow 'em down, starting with the easiest first.
 
DrEntropy said:
Activating the choke on a DCOE allows air/fuel mix in thru a separate circuit with BIG holes behind the throttle plates. The plates/shaft don't move with choke. But it appears from the pix the cable is attached and choke is shut. Tho I have seen the tines of the choke piston actuators break and allow the pistons to rise on their own. Many factors involved here, trying to narrow 'em down, starting with the easiest first.
Click to expand...
Ah, I need to look at one of these sometime. I think you are getting close to the problem talking about holes behind the throttle plate, its another source of air with the butterflys closed then. Hmmn, next time at a car show I want to see one of these. I know they are supposed to be one of the best for performance.
 
Next best thing to injection.

If a DCOE is set up right, they're rock proof.

Only car in my sigfile without DCOE's is Diesela... and if I could figger a way to adapt a set to a five jug squish-bang SHE'd have 'em too. :wink: :jester:
 
Still working through this problem...

Just measured the float levels from the bowl cover/ gasket. Here's what it's reading:

Full Drop: 15.72mm
At Rest/ Just Touching: 7.73mm
Closest to Cover/ Float All the Way Up: 4.82

Everything I've read say that the top 2 measurements are all that matter. I assume that the at rest measurement is the more important of the other 2 as it's the one that determines when the valve is actuated.

On the DCOE carb, the float level is adjusted "by bending the float arm tab that presses against the float needle assembly."

will post results shortly...
 
OK, I adjusted the float movement and now it's measuring 8.47 and 10.55. I'm happy with that. I adjusted the tabs that limit the movement of the floats by simply squeezing them towards each other as they are positioned in an L shape at the fulcrum point. I don't want to risk taking either movement past the desired measurement as it appears that adjustments in the opposite direction would be pretty difficult.

I wonder if my living room smells like gasoline. I can't smell it anymore but I can only imagine! Back out to the car...
 
DrEntropy said:
Another thought: insure the ball valve at the bottom of the bowl (#43 in that diagram) is snugly fitted to the bowl. Only way to test it tho is to remove it and that means allowing fuel to dump into the intake... or sopping the fuel out with paper towels first. Then it's the same test procedure as the cloat valve... blow from the "bottom" it should pass air. From the top, not.
Click to expand...

THIS MIGHT BE THE PROBLEM. I just checked the valve when I went out to install the newly adjusted floats. The ball valve is performing opposite to how Dr. E. said it should. Air is definitely able to go from top to bottom but not the other way around. It's passing from the slotted side (bowl side) towards the bottom (threaded side). It seems to me that that's the way fuel would want to pass but I don't know these carbs.

I reinstalled everything to see if the float adjustment fixed the problem but it still wouldn't start.

ugh
 
valve1.jpg
 
that tab should not move, it holds the checkball in place.

My turn to be brain-dead. It's working properly. :shocked:
 
Jim will sort it out, certes.

We still wanna know what it is that caused this, Sean.
 
theleisure said:
I gave up. Off to Boffo Motor Works.
Click to expand...

good call - sometimes you just need to git 'r done
 
I picked up my car yesterday and I'm happy to say that it started right up today. They said it was an issue with- get this - the floats. Doh. I'll always wonder if some kind of blockage worked its way loose while the car was getting towed but who knows. I'm thrilled that it's running again.

In other news, I'm expecting 1-3" of this superfine white stuff inside my car by evening rush hour. It's funny to look around while your driving and see that it's snowing inside your car as much as it is outside of the friendly confines of your softtop.
 
glad it is working - Ms Triss is watching it snow through the garage window and grumbling. (Or at least her owner is)
 
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