carburettor engine hot start problem

[Gerhard]

Hello togethe,

 

I've a hot start problem with my Robin Hood. When I get the engine on 80° Celsius and turn it of, I have to wait about 10 minutes to restart it. Normaly it's not a graet Problem, but when I stopp at a Gas station to refuel, I had also to wait. Mostly I have to push the car away from the gas pump. That's not so funny.

Has or had anybody the same problem, or could fix it?

Thank you and greatings form the very warm Germany

Gerhard

[alanrichey]

I know your details say you have a ‘Super Seven’ but do you actually have a ‘Super Spec’ ?   If so this is a known problem with this design.  Various suggestions have been made:

1.  Poor earthing  (Add an extra earth strap between engine and chassis)

2.   Overheated starter motor  (I have added a tube from the front of the car pointing at the motor to try and keep it cool)

3.   Poor battery (fit a new one)

4,    Ignition advanced too much (in theory the ECU programming is at fault)

5.    Tolerances to tight between starter motor and flywheel (Not much you can do about that)

I have fixed the first 3 and don’t suffer any more.

if you don’t have a Superspec the above might still be useful.

Al

[Gerhard]

Thank you for your repley.

1. Ok, there are three straps

2. Ok, no problem

3. Batterie is new

5. The engine turns

The starting problem is only while the engine is warm. When I wait about ten minuten, everything is fine and the engine starts on the first turn.

[richyb66]

So the engine is turning but it won't start? 

That leaves fuel and ignition and the problem is probably related to heat build up. I'd probably start looking at ignition first, possibly the coil or the ignition module if you have electronic ignition. 

[Gerhard]

That's all checked and ok. In cold Status, the engine starts in first turn, also in hot status after 10 minutes.

I think it's a problem with heat and the carburetor. I took a hose with a fan nein to it to cool it. It don't work.

[richyb66]

Ok, next thing is are you having problems with the fuel in the carburetor evaporating? Can you try a bit of fuel down the carb inlet and see if it starts. Underbonnet heat can be a problem but normally the fuel takes time to evaporate, not like when you part up to put fuel in. If you have a mechanical fuel pump, sometime is can struggle to refill the carb and it takes a lot of cranking. An electric fuel pump normally fixes this issue.

One other thing, did your welcome pack get to you OK?

[Gerhard]

I received the Packard and everything was ok.

Thank you.

I tried the mechanical fuel pump in cold condition, there it works fine. Maybe I should really check it in hot.

[Gerhard]

But one question, when I stop the engine and try to restart it immediatly - should there not be enough fuel in the carboretor?

Rember: it's always the same situation.

[Gerhard]

I found the problem!

The engine was also available with an catalyst. So I used unleaded petrol. Now I read in an workshop book that you, if you did so, should turn the ignition timing a bit later. Since the engine works good while running, I decided to ad lead addition to the fuel. It works! No more hot start problem.

It could be so easy!