Warm starting - 2l carb

[JohnFol]

Hi all, when engine is cold, I turn ignition on to get huco fuel pump running. I then press accelerator twice to set choke and  it starts pretty much straight away.

However when warm It eventually fires but only after 20s of cranking and random accelerator presses

The car has electronic ignition, DATR carb. I've replaced leads, cap, rotor, plugs, coil, battery, battery leads and ignition switch. Distributor, carb and alternator all overhauled (by experts) and starter is a wasp high torque that's energised via a relay not from ignition barrel.

I'm thinking it's user error so interested what works for others.

[peteracs]

Hi John

Well assuming all the new items are good (coil would have been my first port of call), I would suggest maybe flooding in the carb. When you crank does it smell of petrol at the exhaust? If so I suggest maybe faulty float/valve? Also what pressure is the carb input regulated to and do you still have the return line in use?

Peter

[JohnFol]

Hi Peter, return line is blocked so pump shuts off when float is high. Not noticed any petrol smell but will have a sniff next time. Not got a separate fule pressure regulator fitted.

In terms of "technique", I know about resetting the choke with a press on the accelerator when cold, but what is the "right" way to start when engine warm?

[JohnFol]

Just found this. Seems to be... If in doubt press accelerator.

[peteracs]

Hi John

Normally when warm, no need to touch the accelerator until the engine fires. If it is flooding, ie too much petrol vapour, then remember when you press the accelerator the accelerator pump literally pumps petrol into the carb, I use this to get the engine going when cold by pumping the accelerator a few times before cranking. This also sets the auto choke of course. When warm the auto choke should remain open, that is also worth checking.

If flooded then pressing the accelerator to the floor will help get max air into the cylinders, but do not pump for above reason.

Peter

[squiglyzigly]

Hi John,
My 2.0L Berlina does the same thing and I know for sure that it is flooding due to heat soak. If you want to check if yours is the same issue then take the airbox lid off after it’s been driven around and is nice and hot. You can see the fuel dribble down the chokes and into the inlet manifold.
So the best way to start it is to hold the throttle half or full down and crank. As Peter says, no pumping the throttle pedal.

This is not a fault with my float level or any other part of my car, just purely heat soak. The carb is hot too touch when its been on a run in summer and the engine bay is cooking.
I have an insulated spacer between the carb and inlet manifold but clearly this is not enough. One day i plan to fit the insulator between the head and the inlet manifold as fitted to injection models to see if this makes a difference. But my list of jobs is long and this is way down the list.

Good luck
Ian

[JohnFol]

Many thanks all for the replies.
Sounds like I have a few things to try.