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Discussion Starter #1
The spica to carb conversion is complete and the car starts but dies after a few seconds.
What's in it:

*facet fuel pump 4psi
*filterking fuel filter/regulator (unadjusted, if it need adjustment I don't know how to do it)
*thoroughly cleaned and rebuilt DHLA40's
*carbs fitted with standard jets and emulsion tubes for a 2l per jetting.exe, carb books and consistent recommendations from a number of you.
*euro camshafts with 2l euro timing (using centerline templates and not the US camshaft bearing mark)
*static timing set a 7* BTDC as per euro specs (yeah it's different from the 2*- 4* published in US)
*tried every.5 turn setting from 1 to 5 turns out from seated on the idle adjustment screws

Because it starts I suspect a fuel delivery issue rather than an ignition problem. The first thing I rechecked was to make sure my carb fuel floats were properly set and I confirmed the 15mm and 25mm travel respectively in the up and down float position (from gasket to float top) but I was surprised to find just 30mm of fuel as measured on the bowls closer to the fender. Does that sound right? The level is consistent on all 4 carb bowls.

Here are a couple of pics of the fuel level. Any other recommendation as to where I should look? Thanks!
 

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are you using the chokes (bypass actually) or just kicking the accel pumps? on my Dell'ortos, I finally hooked up the bypass and a hand "choke" knob, much easier starts and keeps running from cold start.
cliff
 

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Discussion Starter #3
Cliff, I haven't hooked the choke cable yet and wasn't really thinking it would be necessary considering California weather.

I read a post in which 29mm fuel level was discussed for a weber but I'm not sure if it was measured similarly.

Thanks.
 

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I run 45 DHLA on my 2liter engine and I never use the choke. You can do that on
Dell'Orto carbs but not on Weber carbs

Happy Motoring
 

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Oh Sorry, if you don't use the Kingfilter than bypass disconnect it or run a bypass. My 2 cents that that's the problem.

Happy Motoring
Rob
 

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Discussion Starter #6
Rob,

you are right, the kingfilter was my problem. I bypassed it and no longer have the fuel delivery issue I had. I'll take it apart to see what's up. I noticed that it's "adjustable" ... (scary word). Would you happen to know which way the top screw should be turned for more fuel pressure?

Thanks.
 

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I am not 100% convinced that you need a fuel pressure regulator with Webers. Yes, I know the factory used a regulator on the Veloces. But, with the proper fuel pump output pressure, and with the pump installed at the rear of the car so that the long fuel line acts as an accumulator, I believe that the carbs receive a consistent supply of fuel at the proper pressure.

Now, the FILTER function of the regulator/filter probably is important.

Given that Alfaseb has a regulator mounted, he should probably experiment with the adjustment screw cranked all the way left, then all the way right, to see if the car will run on either extreme setting. If having the regulator bypassed produces satisfactory operation, then having it cranked all the way into unregulated territory should produce similar results.

I'm sure there will be rebuttals.....
 

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Rob,

you are right, the kingfilter was my problem. I bypassed it and no longer have the fuel delivery issue I had. I'll take it apart to see what's up. I noticed that it's "adjustable" ... (scary word). Would you happen to know which way the top screw should be turned for more fuel pressure?

Thanks.
Hi Seb, No I am sorry but I never dealt with the actually adjusting them. But when you open up the housing you can figure out what it does. But why bother it's working. Replace the regulator with a good in-line fuel filter.

good luck and Happy Motoring
Rob
 
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