Cold Non-Start

How old is the battery?

I might be lead to believe that a tired battery could crank the starter (do you have an old, lazy starter that cranks relatively slowly?) without generating the necessary oomph to get the car to fire, which would be exacerbated (how's that for a word) by the cold weather.

DO NOT USE THE CHOKE. IT'S ORNAMENTAL.

DM

 

i thought i was the only one who thought that. i have never used the choke on the dino and could never figure why someone would (but then again, i have never driven the dino in very cold weather)

 

The choke at best is best left alone. Usual procedure is wait a few seconds for the fuel pump to pump and then to pump the throttle 3 times and crank.
I you flood it, floor the throttle and crank till it starts. Have you checked points and ignition system lately?

 

I know to pump 3 times starting cold, but I don't know why. Can someone please explain the theory behind?

 

the car firing when pushed but not when rapidly turning over makes no sense to me, as the engine is being rotated either way.

Pumping the gas pedal squirts raw fuel into the intake system because you activate the acceleration jets. These consist of a little lever arm behind a rubber diaphragm, and as you step on the gas it pushes the diaphragm in and squirts (literally) gas into the carb throat. This then evaporates and enrichens the mixture, leading to firing.

My car has 40 IDF carbs rather than the stock ones, but the choke works great. A properly set up choke also has a fast idle arm that keeps the revs up as the engine warms and progressively decreases as you let the choke off.

For those of you who never use the choke, do you have to keep pumping the gas to keep it running after it fires?

Jim

 

the car firing when pushed but not when rapidly turning over makes no sense to me, as the engine is being rotated either way.

Pumping the gas pedal squirts raw fuel into the intake system because you activate the acceleration jets. These consist of a little lever arm behind a rubber diaphragm, and as you step on the gas it pushes the diaphragm in and squirts (literally) gas into the carb throat. This then evaporates and enrichens the mixture, leading to firing.

My car has 40 IDF carbs rather than the stock ones, but the choke works great. A properly set up choke also has a fast idle arm that keeps the revs up as the engine warms and progressively decreases as you let the choke off.

For those of you who never use the choke, do you have to keep pumping the gas to keep it running after it fires?

Jim

 

My US spec car has a functional idle advance. When the car is cold, a little wheel on top of the forward cylinder bank slightly advances the idle (500 rpm) and slowly backs off as the head gets warm.

Took me two years to find the parts to make it work, but when I did, it has made a major difference in the way the car runs when cold.

DM

 

Pandino:

when push starting, the battery is not being drained by the starter and can give all its attention to the ignition. Typically the engine is spun much faster on a push than by the starter, that helps also, but the ignition issue is the main one. As you stated, each pump squirts juice into the chamber, so too much pumping and the mixture may be too rich, engine won't fire and the plugs will be fouled with gas. 3 pumps seems to be the magic number.

 

Mine was hard to start on cold mornings. Threw away standard plugs, went to platinum/iridium. Problem went away. I used to live on a hill and used to have to roll down hill to crank, battery only had to fire ignition. Seems that the diference between 12/13 volts going to ignition and 8 when cranking makes a huge difference. Small electrode plugs are magic. NGK iridium, #7 heat works just fine.

John

 

Is that the square thing on the front bank cam cover that I see on Us cars?

 

Nope.

This is it.

DM
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Dunke!

 

Check the battery even though it's new. It may be weak for various reasons. Also, how old is the ignition coil and wires? You may be getting a weak spark that only manifests itself when you need it most; I'd check the obvious electrical system components. I had the same problem last week with the Lotus; my 6 year old battery cranked the engine okay in 25 degree weather but it wouldn't start. Starter spray fired it up, and I bought a new battery. Starts like a real car again!

Ken

 

...and have you replaced the Marelli CD ignition box with something more modern and powerful. If not, this might be your problem.

 

My starter is really really weak, it only has enough juice to crank for 1-2 seconds before it stops completely and it sounds like I'm starting with drained battery. It amaze me that I am still able to fire up the engine on first crank most of the time, and I usually don't need to hold the gas for more than a few seconds. Maybe my high idle speed(1100rpm) is helping. The choke is disconnected, can I use it to control just the rpm advance?

 

It's most likely the temp. that has affected the battery output. Air temperature decreases will drastically reduce battery output. I've always lived in relatively warm areas, but I have heard that people actually would put their batteries in the oven on very cold days to maintain the output. If the battery is not at it's optimum level to begin with, there is a potential for the battery to be just to weak to start the engine.
Scott

 

I wonder how important can the Dinoplex be. My car has no dinoplex or any other electronic ignition system, and it still fires up on first crank.

 

Do you think you may have gotten a little condensation in the distributor cap from the colder weather? It might be worth removing it, inspecting it and blowing it our with compressed air.

 

Not compressed air; use a warm hair dryer. If that solves the problem, you'll need to replace the cap as it has a leak somewhere even if you can't see a crack.

Ken

 

Check the voltage at the coil while cranking. I would bet you will see around 8 volts and will track it back to melted connections at the amp gauge. Been there 3 times this summer with identical symtoms.

Dave