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Discussion Starter #1 (Edited)
Hi everyone, I'm the new owner of a 72 Manta 1.9 (electric fuel pump installed and Dell'orto carbs) and have a start issue. Currently it takes about 4 attempts of turning the key and cranking for about 5 seconds to start up when starting from cold. First try, it cranks and starts for just a second, then sputters out. When I turn the key again, it'll turn over but won't start even momentarily. After a couple more attempts and while holding down the throttle, it will eventually start. . Once the engine is warmed up it will run and start again fine.

This is actually my first carbureted car, so I'm a noobie when it comes to carbs. I'd appreciate any direction, however basic!

The previous owner allegedly had no issues with cold starts. I know I'm getting enough fuel to the carbs with the fuel pump whirring. Could this issue be a symptom of flooded carbs, or possibly an electrical (ground) issue? Also, I don't have a choke installed - how much of an impact would this have?
 

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boomerang opeler
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how much do you put on the cold start /choke when first starting it ?
iirc the dell'orto's are like the weber dcoe and have a fuel enrichment valve that dribbles raw fuel into the venturi to add more fuel when starting from cold
 

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Also, I don't have a choke installed - how much of an impact would this have?
A lot. Cold engines need to run rich (higher fuel/air ratio) until they warm up. Can you have a manual choke installed?
 

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Discussion Starter #4
how much do you put on the cold start /choke when first starting it ?
iirc the dell'orto's are like the weber dcoe and have a fuel enrichment valve that dribbles raw fuel into the venturi to add more fuel when starting from cold
Hey, thanks for the info. I'm sorry, I don't think I understand your question. Forgive me, I'm still a complete noobie when it comes to carbureted engines. It makes no difference if I pump the gas pedal before cranking, if that's what you were asking. I also let the gas pump run for about 5-10 seconds beforehand.
 

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A lot. Cold engines need to run rich (higher fuel/air ratio) until they warm up. Can you have a manual choke installed?
Ok, I'm sure I could rig up a manual choke. I'm running double dual-throat Dell'ortos, so I assume I first connect both of the choke valves together, then rig up the choke cable... any recommendations on the routing of the cable, or does it really matter?
 

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boomerang opeler
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a carb usually has a flap that restricts air flow called a "choke" plate , this makes the engine pull more fuel in when cold to help it run
side draft carbs like the dell'orto's tend to not have this they have a valve that runs raw fuel into the venturi to make it run rich
so if you are not pulling open the valve ( there will be a knob in the cockpit , could be marked "choke" ) it will not get enough fuel to start and run

phone the previous owner and ask him to talk you through starting it as he will know where this is
 

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Ok, I'm sure I could rig up a manual choke. I'm running double dual-throat Dell'ortos, so I assume I first connect both of the choke valves together, then rig up the choke cable... any recommendations on the routing of the cable, or does it really matter?
Route the cable to easiest route for you. As long as you have free movement of the cable, you should be fine. Full choke when you start and gradually open the choke for the first 5 min of running. You will get a feel for it.

If they sell an automatic choke for this carb, look into it.
 

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Discussion Starter #8
Route the cable to easiest route for you. As long as you have free movement of the cable, you should be fine. Full choke when you start and gradually open the choke for the first 5 min of running. You will get a feel for it.

If they sell an automatic choke for this carb, look into it.
Roger that. I don't think they have an auto choke for this carb, so it would have to be manual. I just chatted with the previous owner, who said that he'd get no starting problems after pumping the gas pedal 10-20 times prior to cranking, which from what I've read seems slightly excessive.
 

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AFAIK there are no automatic chokes available for side draft carbs. Run the choke cable as has been suggested with no tight bends that restrict cable movement. Every engine seems to have a combination for easy starting whether it be pumping the gas pedal 1 time or 3 times and choke or no choke once it's warm.

Harold
 
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