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Discussion Starter · #1 ·
on the dhla cold start circuit, when the lever is moved toward the front of the engine/radiator is it enriching the mixture?

i have read that to start the idle mixture screw is turned 2 &1/2 turns out. the carb is marked dhla. a good place to start?

thanks

bill
91 164L
88 Milano 3.0
73 spider and gtv
 

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Bill,
If my memory serves me, moving the choke valve lever to the rear of the car on right side mounted carbs will activate the cold start circuit. They should spring return to the front of the car and to the normal operating position.

I am assuming you have installed new carbs to your car and you are trying to get the car started/running. I have various dellorto and weber carburetor manuals and troubleshooting guides in electronic format that I can send you by email. The weber and dellorto carbs are similar in form and function. Send a PM to me with your email address and I can send you the manuals.
 

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Discussion Starter · #3 ·
alex thanks for your kind offer, pm sent.
i have the haynes weber manual and pat bradens weber manual.
i found a description of the cold start circuit on page 143 of the haynes.
i have just put a pair of dhla's on my spider and just want to be sure they operate in the same way as the weber's however as i think of it why would the choke lever operate differently.
thanks again

bill
 

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Discussion Starter · #4 ·
I got the carbs on today and started with the idle screws at 2 1/2 turns out.
the car started right up and I drove it around the block, it stalled at stop signs a couple of times until it warmed up. now it idles a little low but even and it runs and pulls great. no time left to play with it today.
 

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... and just want to be sure they operate in the same way as the weber's however as i think of it why would the choke lever operate differently.
Bill:

Well right, there is no reason why Webers would operate one way, and Dellortos the other. However, there IS a reason why both types of carbs would come in "pull left to choke" and "pull right to choke" versions: some engines mount their carbs on the right side (like Alfas), and some on the left side.

The Weber enrichment device uses a lever to rotate the shaft that controls one barrel, and a pair of gears to drive a second shaft that controls the second barrel. See part #42 on the diagram below. Mirror image choke parts exist that attach the actuation lever to the other shaft, so that the mixture is enriched when you pull in the other direction.

Dunno if Dellortos have a similar means of reversing the direction of pull to enrich the mixture - I'm less familiar with them.

Moral: When buying a Weber on ebay, study how the choke operates. It may have come off a car with the carb on the left side of the engine.
 

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the idle screws only set the mixture, the idle is a screw between the carbs that stops the travel. there is another that ballances the two carbs. setting the idle mixture is necessary when you get excessive popping on deceleration. back off all four (screw out) a half turn at a time till it stops. te idle mixture screws can also be used to fine tune the idle for minimum shaking on idle after warmed up.
cliff
 
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