hello folks, I have a little problem with the start when engine is warm.
When cold it start with a half turn key, after a break of 5 minutes, it restart well as it should with a half turn key, but after a 15 minutes break, I must insist with the key, sometimes 4 or 5 turns. But, and here the strange, after a long break, 2 or 3 hours, it start as well as it should with a half turn key. I asked my carb specialist, and he says that could be a matter of vapor lock, One of the guys that have american car says that could be a temp sensor thsat does not work as it should and gives wrong information to the carb. A TEMP SENSOR???? Possible? these engines have temp sensor ??? I haven't found anything about in the owner manual. the only thing I found about cold and warm switch on is that when cold it must engagé the stasrter and turn the key without press the trottle, but when warm must press the trottle for half its stroke and turn the key. I do so, but after a 15 minutes break it needs 4 or 5 turns of the key to start. Some suggestions? the engine is the 350 with a 2 barrells carb and seems all original, but I'm not sure about

 

The temp sensor he is referring to is probably the choke. Make sure when the car is fully warmed up that the choke flap is fully open.

 

hello Eric, I don't know where the choke is placed, IO suppose in the nose of the air filter housing on the top of the carb, in effect there is a device with a hose on the down side that arrive to the carb, but I don't know how to control it, but surely my mec knows it. Actually the car is at the body shop for a little restoration, as I decided to remove the rusty spots in the fenders and the rockers, I will check your suggestion the first time I will use the car after restoration, in effect some thing wrong must be in, as last times, even when warmed, it remained accelerated, and I had to push down the trottle to find its natural idle, while before it arrive to its idle naturally wqhen warmed. Thanks Eric, I will let you know

 

The choke is on the right (passenger) side of the carb. Your symptoms describe a choke not pulling off once the car warms.

 

Agreed. With the choke closing when it is NOT supposed to [warm engine] the mixture is becoming too rich. Therefore it needs more air. Opening the throttle partway will let more air it to help but what you probably need to do is to open the throttle ALL THE WAY which then engages the choke unloader system as well. This feature, specifically engineered and put in place to alleviate a flooded engine, gives the driver more control over the choke by forcing it open at least a bit. Plus the main throttle is then 100% open for max air flow. Sure you get ONE shot of accelerator pump fuel, which makes for more richness, but if you depress the gas pedal exactly ONCE, and to 100% open, that is how to cure an excessively rich {flooded} engine.

This feature is probably described in the owner's manual, and certainly described in the chassis service manual's carb section.

A good cleaning of the choke mechanism, and adjusting it properly, and checking the thermal coil, wouldn't hurt. Make sure that the carb is opening 100% when the gas pedal is all the way down, and that this causes the choke to be opened a bit even if it wants to be closed.

 

Mhm it's not that I have understood so much in what you wrote man, but when it will be the moment(when the froggy will be ready from the body shop) I will contact the carb specialist, surely he knows , and in the meantime I will ask my mec what he think about . thank you anyway and happy new year to everybody