Hello wise people of the internet.
My Favorit has an issue that if I start it after sitting for more than 5-6 hours it will start normally but after 2 minutes it will stall and wont start for almost 10 minutes, after that it runs and drives great like nothing happened.
I have replaced the carb, choke and distributor and still this happens.
Even deleted the choke completely (in my warmer climate its not needed so much) with no change, checked for spark and was getting spark (cant tell if weak or not).
Thinking about changing the ignition module and coil with hopes that it will help.
No mechanic would have a look on it because no one works on older cars here so Im on my own.
If anyone can give their opinion on this please feel free to do so.

I know someone with very extensive experience @R_Blue

Hi,

I've also checked your previous topic.

You had issues with the carburetor setup.

Now;

 

14 hours ago, OmerGarabagi said:

I have replaced the carb, choke and distributor and still this happens.
Even deleted the choke completely (in my warmer climate its not needed so much) with no change, checked for spark and was getting spark (cant tell if weak or not).

 

- What kind of carburetor do you have right now?

New or used?

Which brand? Jikov? Pierburg? Vika?

 

Since you've said there is spark, we have to check other parts of the system.

 

- Does the new carb have been adjusted for correct idle mixture?

- Does the carb have earth connection to the engine? (Important safety detail. If there is no earth connection from carb to engine, sparks can happen inside the carb. causing fire)

Also, please check if the engine is connected with a proper, non-rusted earth strap to the chassis.

 

- There is a part on the carburetor called the carburetor solenoid. It cuts fuel when the ignition is off. There might be issues with stable electric delivery to that part due to corrosion. If the cable providing power to it, is corroded from inside, you might having the fuel cut off.

Please ensure the carburetor solenoid is working properly. If the carburetor is not earthed, there may be problems with this part's operation too.

 

- The cold start procedure for an engine is not only vital for cold climates.

For proper cold starting, there are helper components and adjustments on the carburetor. They all work with conjunction with each other.

The engine, when it's cold, is hard to turn. (By cold, I mean even at 20ºC)

So you need a higher idle setup* to be able to hold the engine at the same 800rpm level.  There is an adjustment on the carburetor called "fast idle". It's a screw sits on a cam which looks like stairs. It overrides the idle adjustment screw's setting when the engine is cold by providing higher opening degree for the throttle flap.

(*= Higher angle throttle flap position for more idle air. But that doesn't mean you'll get more fuel because the carburetor is cold and vaporization of fuel is low. So carburetor uses choke to increase air flow and suction from the fuel chamber. Some carbs have electric heaters built-in.But Jikov doesn't have that! So auto-choke operation is important)

Does your carb's fast idle adjustment is correct?

 

And you also must check proper fuel delivery and circulation.

But before performing that, you must determine if the car is running rich or lean just before stalling.

If the problem is from incorrect mixture level, you can tell by using your nose to sniff the exhaust.

If it's too rich to the point of stalling, the exhaust will smell very acidic and you can't stand the smell for mere seconds. It will make your eyes sore and tearful just in seconds.

If it's too lean, it will smell just like air before rain.

But, please don't smell it too much. Exhaust smoke is poisonous. It will cause dizziness even with very small doses. (In modern cars, the lambda sensor is doing this for us. Which can also be retro fitted in a carburetor car to provide helpful info for precise carburetor adjustments)

 

Also, please tell us more details about how the car starts? how does it idle after the start? just before stalling, does the idle decrease? If you keep the rev. at 1000rpm by pressing the gas pedal does it survive from stalling after 2 minutes?

 

With more details, I think it can be solved eventually.

2 hours ago, R_Blue said:

Hi,

I've also checked your previous topic.

You had issues with the carburetor setup.

Now;

 

 

- What kind of carburetor do you have right now?

New or used?

Which brand? Jikov? Pierburg? Vika?

 

Since you've said there is spark, we have to check other parts of the system.

 

- Does the new carb have been adjusted for correct idle mixture?

- Does the carb have earth connection to the engine? (Important safety detail. If there is no earth connection from carb to engine, sparks can happen inside the carb. causing fire)

Also, please check if the engine is connected with a proper, non-rusted earth strap to the chassis.

 

- There is a part on the carburetor called the carburetor solenoid. It cuts fuel when the ignition is off. There might be issues with stable electric delivery to that part due to corrosion. If the cable providing power to it, is corroded from inside, you might having the fuel cut off.

Please ensure the carburetor solenoid is working properly. If the carburetor is not earthed, there may be problems with this part's operation too.

 

- The cold start procedure for an engine is not only vital for cold climates.

For proper cold starting, there are helper components and adjustments on the carburetor. They all work with conjunction with each other.

The engine, when it's cold, is hard to turn. (By cold, I mean even at 20ºC)

So you need a higher idle setup* to be able to hold the engine at the same 800rpm level.  There is an adjustment on the carburetor called "fast idle". It's a screw sits on a cam which looks like stairs. It overrides the idle adjustment screw's setting when the engine is cold by providing higher opening degree for the throttle flap.

(*= Higher angle throttle flap position for more idle air. But that doesn't mean you'll get more fuel because the carburetor is cold and vaporization of fuel is low. So carburetor uses choke to increase air flow and suction from the fuel chamber. Some carbs have electric heaters built-in.But Jikov doesn't have that! So auto-choke operation is important)

Does your carb's fast idle adjustment is correct?

 

And you also must check proper fuel delivery and circulation.

But before performing that, you must determine if the car is running rich or lean just before stalling.

If the problem is from incorrect mixture level, you can tell by using your nose to sniff the exhaust.

If it's too rich to the point of stalling, the exhaust will smell very acidic and you can't stand the smell for mere seconds. It will make your eyes sore and tearful just in seconds.

If it's too lean, it will smell just like air before rain.

But, please don't smell it too much. Exhaust smoke is poisonous. It will cause dizziness even with very small doses. (In modern cars, the lambda sensor is doing this for us. Which can also be retro fitted in a carburetor car to provide helpful info for precise carburetor adjustments)

 

Also, please tell us more details about how the car starts? how does it idle after the start? just before stalling, does the idle decrease? If you keep the rev. at 1000rpm by pressing the gas pedal does it survive from stalling after 2 minutes?

 

With more details, I think it can be solved eventually.

Hi, thank you for responding.

- About my previous topic, I had 2 issues, one was “fixed” by replacing the carb to the current one I have on the car, the other still remains even after the carb replacement (this topic).

- I have a used pierburg 2e3, cleaned it from the inside, new accelerator pump, didn’t need any tuning because it runs great.
- Havent touched the idle screws of the carb since it runs great and with the previous carb I had the same issue so I thought it wasn’t the carb causing it.

- The carb has an earth connection to the engine and the engine is connected with a good earth strap to the chassis.

- I have checked the solenoid, it gets constant 12v (with ignition on) and has good earth connection.

- Fast idle is set to around 1800+/- rpm, choke closes and opens as it should with temp.

- The exhaust smells like an old car’s exhaust, doesn’t smell really bad or makes me ill, can I check the spark plugs after it stalls and if they are too wet from fuel it means that its too rich?

- The car starts like it should on cold starts, fast idles on 1800+/- rpm, choke partially closed and slowly opens, feels like a normal car for 2 minutes but after that it stalls then starts for a few seconds then stalls again and wont even start at all for about 10 minutes, even if I hold the throttle when it runs it stalls, like I cant control it.

After about 10 minutes it starts and drives great like nothing happened, and after I finish my drive and turn it off and let it sit for less than 5-6 hours it starts up like a champ.

I tried playing with the choke flap and held it on different positions, tried adjusting the choke, tried disconnecting the choke and even removed the flap completely, tried starting with no fast idle.

No matter what I do I cant prevent it from stalling after 2 minutes on cold starts.

Because I replaced the carb (to the current one I told about in the beginning) and tried all of the stuff I said again and this still happens I thought on moving to ignition stuff.
I hope this information helps you, and again thank you for helping.

 

Edited 16 January, 20251 yr by OmerGarabagi

4 hours ago, OmerGarabagi said:

- About my previous topic, I had 2 issues, one was “fixed” by replacing the carb to the current one I have on the car, the other still remains even after the carb replacement (this topic).

- Momentary stall after pressing gas pedal: Injection volume adjustment needed. Rough idle: Mostly from an air leak or incorrect idle mixture setting.

Do you still have the old carb?

 

4 hours ago, OmerGarabagi said:

- I have a used pierburg 2e3, cleaned it from the inside, new accelerator pump, didn’t need any tuning because it runs great.

It could be from any car from its era or, it could be from a VW T3 Bus! Maybe it's running but that doesn't mean it's running great. "Great" for a carb means; giving ideal mixture ratio at various load conditions. This will provide maximum power with minimum fuel requirement.

Maybe it's running rich all the time but you can't tell the difference without measuring the exhaust with a lambda probe on a live run.

If it's rich, you'll waste fuel. Plus, there will be carbon buildup inside the engine causing troubles later. If it's lean, you'll end up  with very hot burning chamber. Which may cause damage to the valves.

All jets must be adjusted properly for the healthy long-term operation of the engine.

 

5 hours ago, OmerGarabagi said:

- The car starts like it should on cold starts, fast idles on 1800+/- rpm, choke partially closed and slowly opens, feels like a normal car for 2 minutes but after that it stalls then starts for a few seconds then stalls again and wont even start at all for about 10 minutes, even if I hold the throttle when it runs it stalls, like I cant control it.

It shouldn't run that fast when it's cold. I'd decrease it.

 

5 hours ago, OmerGarabagi said:

- The exhaust smells like an old car’s exhaust, doesn’t smell really bad or makes me ill, can I check the spark plugs after it stalls and if they are too wet from fuel it means that its too rich?

Spark plugs can tell many about the health of an engine.

 

If you post the pictures of them, many members here can tell you about engine condition.

Please be careful when re-installing the spark plugs. You don't want to strip the threads on the aluminum head. Don't over-tighten the plugs too. (26nm for flat-seat washer type plugs)

 

 

Before advancing further, please reduce the fast idle speed by turning the fast idle screw counter-clock wise. Reduce it to a level, so the engine runs around 1000-1100 after the cold start.

 

After that, perform these tests:

- After the cold start and before the engine stalls, rotate the idle mixture screw counter-clock wise and listen to the engine if it increases the idle speed or not, as soon as you start rotating the screw. (Mark the position of the screw before trying this)

- After the engine stalls, remove the distributor vacuum line and try starting again.

 

You've said, after stalling, it starts for a brief moment and dies again.

Please try this and tell if there is any difference. After the engine dies, pump the gas pedal 3 times and start again. What happens this time? Completely zero ignition or more running time?

32 minutes ago, R_Blue said:

- Momentary stall after pressing gas pedal: Injection volume adjustment needed. Rough idle: Mostly from an air leak or incorrect idle mixture setting.

Do you still have the old carb?

 

It could be from any car from its era or, it could be from a VW T3 Bus! Maybe it's running but that doesn't mean it's running great. "Great" for a carb means; giving ideal mixture ratio at various load conditions. This will provide maximum power with minimum fuel requirement.

Maybe it's running rich all the time but you can't tell the difference without measuring the exhaust with a lambda probe on a live run.

If it's rich, you'll waste fuel. Plus, there will be carbon buildup inside the engine causing troubles later. If it's lean, you'll end up  with very hot burning chamber. Which may cause damage to the valves.

All jets must be adjusted properly for the healthy long-term operation of the engine.

 

It shouldn't run that fast when it's cold. I'd decrease it.

 

Spark plugs can tell many about the health of an engine.

 

If you post the pictures of them, many members here can tell you about engine condition.

Please be careful when re-installing the spark plugs. You don't want to strip the threads on the aluminum head. Don't over-tighten the plugs too. (26nm for flat-seat washer type plugs)

 

 

Before advancing further, please reduce the fast idle speed by turning the fast idle screw counter-clock wise. Reduce it to a level, so the engine runs around 1000-1100 after the cold start.

 

After that, perform these tests:

- After the cold start and before the engine stalls, rotate the idle mixture screw counter-clock wise and listen to the engine if it increases the idle speed or not, as soon as you start rotating the screw. (Mark the position of the screw before trying this)

- After the engine stalls, remove the distributor vacuum line and try starting again.

 

You've said, after stalling, it starts for a brief moment and dies again.

Please try this and tell if there is any difference. After the engine dies, pump the gas pedal 3 times and start again. What happens this time? Completely zero ignition or more running time?

I still have the old carb, its also a pierburg 2e3 and it’s the original carb (1 owner car so I know for sure).

The “new” used carb which is also a pierburg 2e3 I removed from another skoda favorit that was sitting in a junkyard after being in an accident, I assumed it was running good before the accident and the adjustment was correct so I just gave it a good clean inside and installed it on my car and it felt much better than my old carb.
I will reduce the fast idle speed and upload pictures of the plugs once I have some time (I have an important job interview next week), hopefully next weekend and will give you an update.

I also tried removing the distributor vacuum line about a week ago and it didn’t make any change.

When rotating the idle mixture screw counter clockwise it should increase or decrease the fuel flow? and If its running too rich when cold can it stall the engine after a couple of minutes? Because the stall happens instantly, it doesn’t show any signs of it about to stall and doesnt lower the rpm gradually.
 

The carb on the favorit is Jikov 28-30 LEKR which is a Pierburg 2E3 clone.  (Marked with yellow arrow) Maybe they had to use original 2E3 for some exports.

If you've pulled it from another favorit, then there should be no problem with the jet setup.

 

Please do this easy test:

 

After the cold start, wait for 1 minutes.

Squeeze the fuel hose marked with green arrow on the picture.

The engine will continue to run. Let it run until it dies from fuel starvation.

Release the hose, start the engine again.

See if it will start.

 

Why doing this?

This is the carburetor's fuel supply line. Cutting the fuel supply by squeezing the hose won't stop the engine immediately.Because, there is a fuel chamber inside the carb. Until it runs dry, the engine will continue to run.

Don't worry about stopping the fuel flow. The part marked with red is the de-aeration chamber. When the fuel chamber inside carb is full, there is a float in there stopping the flow from inside. Like you do now from outside. When the fuel is stopped from entering the carb, it is routed from the de-aeration chamber back to the fuel tank.

 

The float inside the carburetor is connected to a needle with a rubber tip. 

 

 

You've taken this carb from a car sitting in a junk yard.

The rubber tip of the needle might be hardened and not blocking the fuel flow well when the engine is cold. Causing the fuel chamber to overflow.

If the fuel chamber overflows, the engine will stop suddenly. Just like you've described and it won't work until the excess fuel vaporizes from the intake manifold.

 

8 hours ago, OmerGarabagi said:

When rotating the idle mixture screw counter clockwise it should increase or decrease the fuel flow? and If its running too rich when cold can it stall the engine after a couple of minutes? Because the stall happens instantly, it doesn’t show any signs of it about to stall and doesnt lower the rpm gradually.

Idle mixture screw only adjusts air flow of the idle and nothing else.  The fuel is only adjusted by replacing the jets.

 

Have a good luck with your interview.

My god @R_Blue is the carbie master.

10 hours ago, R_Blue said:

The carb on the favorit is Jikov 28-30 LEKR which is a Pierburg 2E3 clone.  (Marked with yellow arrow) Maybe they had to use original 2E3 for some exports.

If you've pulled it from another favorit, then there should be no problem with the jet setup.

 

Please do this easy test:

 

After the cold start, wait for 1 minutes.

Squeeze the fuel hose marked with green arrow on the picture.

The engine will continue to run. Let it run until it dies from fuel starvation.

Release the hose, start the engine again.

See if it will start.

 

Why doing this?

This is the carburetor's fuel supply line. Cutting the fuel supply by squeezing the hose won't stop the engine immediately.Because, there is a fuel chamber inside the carb. Until it runs dry, the engine will continue to run.

Don't worry about stopping the fuel flow. The part marked with red is the de-aeration chamber. When the fuel chamber inside carb is full, there is a float in there stopping the flow from inside. Like you do now from outside. When the fuel is stopped from entering the carb, it is routed from the de-aeration chamber back to the fuel tank.

 

The float inside the carburetor is connected to a needle with a rubber tip. 

 

 

You've taken this carb from a car sitting in a junk yard.

The rubber tip of the needle might be hardened and not blocking the fuel flow well when the engine is cold. Causing the fuel chamber to overflow.

If the fuel chamber overflows, the engine will stop suddenly. Just like you've described and it won't work until the excess fuel vaporizes from the intake manifold.

 

Idle mixture screw only adjusts air flow of the idle and nothing else.  The fuel is only adjusted by replacing the jets.

 

Have a good luck with your interview.

You are right, both the old and the new carbs are Jikov 28-30 LEKR, I thought they were pierburg because they look almost identical and I didn’t give much thought to the stamps (IKOV) on it.
Havent tried the simple test you mentioned yet, but when I cleaned the junk yard carb before installing it I did check the float operation, I exhaled in to the fuel supply to the carb and played with the float simultaneously, it did work properly.
Because both of the carbs have the identical stalling issue I now tried to take a look on the old carb’s float needle to see if there is anything wrong with it but it works good too (didnt remove it completely because I could not remove the float pin that holds them in place because the good tools are at my dad’s house), maybe testing with air isn’t good enough for checking if it will work with fuel pressure?
It just seems so weird to me that both of the carbs fail the same way and under the same conditions 🧐.
I will soon do the test you mentioned and will give you an update after that, and again thank you 🙏.

Edited 17 January, 20251 yr by OmerGarabagi

16 hours ago, Thefeliciahacker said:

My god @R_Blue is the carbie master.

Just an ordinary user. Who tinkers sometime.

 

To be called a "master" in my opinion, one needs to do this job for a living. One needs a workshop with professional tools and a dyno.

 

 

Without a dyno, adjusting anything out of factory spec, takes painfully long time.

 

If you play with a setting in the distributor advance or carb, (plus in my case, LPG adjustments) you must take the car on a test drive.

So what's the big deal? You saying.

It's not that simple.

The car can run fine on a flat road but when I force it on a sharp uphill climb, it may start pinking.

So, one must test it in various circumstances. Not satisfied? Stop, adjust again. Test again.

(When finally done, you might find your car start pinking when traveled to sea level 😒 )

 

15 hours ago, OmerGarabagi said:

It just seems so weird to me that both of the carbs fail the same way and under the same conditions 🧐.
I will soon do the test you mentioned and will give you an update after that, and again thank you 🙏.

You are welcome.

 

So this same issue was present with the old carb.

If the issue is about the carburetor overflowing, you can be suspicious about the fuel return route too. The fuel must return to the tank freely without any restriction. If there is any restriction present in the return route, it will increase the pressure on the float pin inside the carb. You know, the fuel lines are beneath the car. Sometimes they can be physically damaged. Causing a collapse on the line.

On 17/01/2025 at 09:57, R_Blue said:

Please do this easy test:

 

After the cold start, wait for 1 minutes.

Squeeze the fuel hose marked with green arrow on the picture.

The engine will continue to run. Let it run until it dies from fuel starvation.

Release the hose, start the engine again.

See if it will start.

 

Why doing this?

This is the carburetor's fuel supply line. Cutting the fuel supply by squeezing the hose won't stop the engine immediately.Because, there is a fuel chamber inside the carb. Until it runs dry, the engine will continue to run.

Don't worry about stopping the fuel flow. The part marked with red is the de-aeration chamber. When the fuel chamber inside carb is full, there is a float in there stopping the flow from inside. Like you do now from outside. When the fuel is stopped from entering the carb, it is routed from the de-aeration chamber back to the fuel tank.

 

The float inside the carburetor is connected to a needle with a rubber tip. 

 

 

You've taken this carb from a car sitting in a junk yard.

The rubber tip of the needle might be hardened and not blocking the fuel flow well when the engine is cold. Causing the fuel chamber to overflow.

If the fuel chamber overflows, the engine will stop suddenly. Just like you've described and it won't work until the excess fuel vaporizes from the intake manifold.

So I tried it, held the fuel line going to the carb with a vice grip, started the car, it ran for a minute and then stalled, went to check if there is no fuel in the carb (to check if it stalled from lack or fuel or because of the mystery problem) and when I pulled the accelerator pump it was still spraying fuel in to the carb so I think it stalled before running out of fuel.
After that I tried starting it again for a couple of minutes without the vice grip (usual morning routine😒), it sometimes started and idled for a few seconds and then stalled, but if I gave it some gas exactly when it tries to stall I did manage to keep it running but a few second later it stalled as usual even when I still gave it some gas , after a few minutes of fighting it did eventually agreed to not stall and run normally.

22 hours ago, R_Blue said:

So this same issue was present with the old carb.

If the issue is about the carburetor overflowing, you can be suspicious about the fuel return route too. The fuel must return to the tank freely without any restriction. If there is any restriction present in the return route, it will increase the pressure on the float pin inside the carb. You know, the fuel lines are beneath the car. Sometimes they can be physically damaged. Causing a collapse on the line.

About the fuel return line, I did check it about a month ago by spraying compressed air in to the return line from the engine and it was free, went to the gas tank with no problem.
So frustrating...

Edited 19 January, 20251 yr by OmerGarabagi

Maybe it will help if I elaborate on how it happens in different sceneries.
If I start the car and immediately start driving (very bad, only for test purposes), it will drive for a minute but then immediately (with no stuttering)  the engine stops responding to any input and if I shift into neutral it just dies (the car moving in gear keeps the engine spinning).
When I park on a hill (facing downwards, thank god for my house being on a hill) and try to cold start the car and it stalls as usual after a minute I simply roll it down the hill in neutral and I put it in 1st gear and it starts but responds intermediately for a few seconds (gain and lose power on and off for a few seconds) but then its ok and doesn't stall anymore, maybe because nothing is stopping the engine (the car rolls down a hill in gear) the problem resolves a lot quicker (in a matter of seconds).
I cant relax until I find what's causing problem, I've been dealing with this for a few months and it drives me crazy 😂.

So doing the last test did no change. Right?

 

If you had exactly the same problem with the old carb, there must be something related to other components.

You've said you had spark. (After stalling right?) So it's not ignition related. Also you have a new distributor too.

 

The most important component here is the fuel system.  You must determine if there is a too rich or lean mixture.

The last test was about that.

 

At the fuel system beginning, you have a float and pickup pipe inside the fuel tank. There is a rubber hose and the first filter inside. My rubber hose was rotten. It couldn't suck the fuel well, especially if the fuel level was low. I've discovered it after having many frustrations. It was a $0.1 fix.

Later that, there must be an in-line fuel filter placed before fuel pump.  Is it clean?

After that, comes the fuel pump. What is the condition of the fuel pump? There are diaphragms inside. Maybe they are worn and not effective anymore. The fuel pump has a lever which is sliding on a separate lob on the camshaft. There must be a spacer plate between the fuel pump and the engine. If the lobe or the shaft is worn or if the fuel pump is sitting too far because of thick gaskets then, it might not be operating at full power.

It must draw fuel from a long way from the tank you know.

Do not disturb the fuel pump unless you are %100 sure there is a problem with it.

It may start to leak fuel or oil leaks may appear between the pump and the engine.

After the fuel pump, there is the de-aeration chamber and one more hidden filter inside the carburetor hose connection part.

 

If the carb is not overflowing, maybe it's starving for fuel. I've written above for that.

 

I also wonder the root cause of this weird problem.

 

For trying, could you make a bridge connection from battery (+) to the coil (+) which is also connected to the ignition module from there. (Be careful not to short the battery.)

5 hours ago, R_Blue said:

So doing the last test did no change. Right?

 

If you had exactly the same problem with the old carb, there must be something related to other components.

You've said you had spark. (After stalling right?) So it's not ignition related. Also you have a new distributor too.

 

The most important component here is the fuel system.  You must determine if there is a too rich or lean mixture.

The last test was about that.

 

At the fuel system beginning, you have a float and pickup pipe inside the fuel tank. There is a rubber hose and the first filter inside. My rubber hose was rotten. It couldn't suck the fuel well, especially if the fuel level was low. I've discovered it after having many frustrations. It was a $0.1 fix.

Later that, there must be an in-line fuel filter placed before fuel pump.  Is it clean?

After that, comes the fuel pump. What is the condition of the fuel pump? There are diaphragms inside. Maybe they are worn and not effective anymore. The fuel pump has a lever which is sliding on a separate lob on the camshaft. There must be a spacer plate between the fuel pump and the engine. If the lobe or the shaft is worn or if the fuel pump is sitting too far because of thick gaskets then, it might not be operating at full power.

It must draw fuel from a long way from the tank you know.

Do not disturb the fuel pump unless you are %100 sure there is a problem with it.

It may start to leak fuel or oil leaks may appear between the pump and the engine.

After the fuel pump, there is the de-aeration chamber and one more hidden filter inside the carburetor hose connection part.

 

If the carb is not overflowing, maybe it's starving for fuel. I've written above for that.

 

I also wonder the root cause of this weird problem.

 

For trying, could you make a bridge connection from battery (+) to the coil (+) which is also connected to the ignition module from there. (Be careful not to short the battery.)

I have an inline filter before the pump, its about 1 year old and clean, I also cleaned the filter inside the carb when I replaced it (the filter in the old carb was clean too).
I need to check on the pickup pipe inside the tank but it seems odd that it will be an issue only when the engine is cold because its on the other side of the car and not affected by it.
I think I have a small electric fuel pump laying around in my garage, I can try bypassing the mechanical fuel pump with the electric one and see if it makes a difference.
Oh and I replaced the coil a few days ago.
by the way, I just noticed that both of the choke pulldown units on my 2 carbs are cracked in the same place, I did check if the pulldown unit on the carb holds air by breathing in to it and it does so maybe its good and just the plastic case is bad, and because this issue still happens even when I removed the choke completely maybe the pulldown unit doesnt contribute to this. 

The picture if from my other carb that’s not on the engine.

Edited 20 January, 20251 yr by OmerGarabagi

### UPDATE ###

@R_Blue's float needle theory did make sense to me and I wasn't very satisfied from the result of the test with the vice grip.
So I took a small hammer and gave the top area of the carb above the float needle (green circle) a few hits so if the needle was stuck due to temperature maybe the hits will free it.
Got to the car after sitting all night, removed the air cleaner, gave the green circle a few hits, went inside to start the car, and the car didnt stall!
I was so sceptic but it worked, but before I do anything I will try tomorrow morning to start without trying to free the float needle and see what happens, and the day after that I will try to free the float needle and see if it doesnt stall again.
I will update you guys soon.

Edited 20 January, 20251 yr by OmerGarabagi

So the float needle is getting stuck.

Every morning, the engine works with  the residual fuel left inside the carb. When it starts to stall you push the pedal, the injector inside the carb sprays the leftover inside the injector pump giving you the last seconds life and then it dies again.

On 20/01/2025 at 12:22, OmerGarabagi said:

Got to the car after sitting all night, removed the air cleaner, gave the green circle a few hits, went inside to start the car, and the car didnt stall!

I think I was lucky that one time, tried the same thing for a couple of days, the car did stall after all of them, but getting it back running was less of a fight than before.
I need to take a look at the float of this carb and see what is going on with it. 

Another update.

I replaced the float, needle and pin that holds them and it didnt help.
After a cold start the car ran for 2 minutes and then stalled.

 

My next step is to try a cold start again, let it stall then open up the top of the carb and see if there is fuel in the carburetor's bowl, if not then I will try replacing the fuel pump, maybe its acting up when cold. if there is fuel in the bowl then god help me because I replaced everything (except the fuel pump).
Hopefully I will update you guys soon.

Edited 1 February, 20251 yr by OmerGarabagi

On 20/01/2025 at 07:31, OmerGarabagi said:

I think I have a small electric fuel pump laying around in my garage, I can try bypassing the mechanical fuel pump with the electric one and see if it makes a difference.

As it is difficult to check the mechanical pump and a risk to remove it I would clean and check the electric pump and try your idea of bypassing the mechanical pump.  Clean the electric pump for fuel delivery and electric connection.  If possible I would connect directly to the battery live and return for a good powerful electric connection if required you could install an inline on/off switch or fuel valve/tap (subject to fully testing the switch or fuel valve/tap is fully operational and reliable as you do not want to introduce more problems) then before connecting to the carb test the electric pump for correct flow and pressure rates as you want sufficient and possibly not too much to overcome the carb.  Only after full testing of the pump connect it up to the carb and see if that makes any difference to your issue.

 

Lobe operated pumps do need to be fitted in the correct position of lever arm to lobe to work properly.

 

With the 1950s, 1960s and 1970s British engines that I was familiar with many owners that had the mechanical pumps fitted swapped to electric particularly because of starting issues,  and especially if the car had been standing overnight or much longer.  The older versions of the pump IIRC had a priming lever on them that would perhaps have overcome many of the issues.

 

Once an engine or car is running you stand more chance of sorting things or getting to where you want to travel to but if the engine won't start or continue running it is a right PITA (hence also the need of a good battery in good state of charge and health).

 

Even if an old engine runs badly the engine can at least still run and get you to where you want to go.  This was part of the problems with many owners of old cars if they ran, even if not as well as they should or could,  the owners would run them in that way, in ignorance or laziness. 

 

Personally though I do not often recommend stuff from Germany but I found the Hardi electric fuel pump to be fit and forget reliability (for decades from other users and 14 years with my car ownership) and  its performance was good, as it should be it done the job well so was never noticed, fit 'n' forget.  The pumps are basically body and head with selection of fittings to suit requirements so if your car is not listed by them look at the specifications and various heads and fittings available.

 

Other makes of pumps are available those little square ones, the name of I forget now, Facet, can be noisy vibration things that need isolation mounts (basically the old rubber exhaust bobbins) so they can be used, the cube is smaller, perhaps neater but not my preference after having one fitted for a short time, it did not like idle kickover nor I from the noise it made.    

 

Of course your issue might not be anything to do with the pump but it would be good to know for sure it is not the fuel pump.  Often it is the last thing you check that is the problem that is Sod's Law, if an issue(s) can be checked from the opposite ends of a route Sod's Law is you pick the wrong end to start at, but at least checking all other items means they are either checked or adjusted or attended to.

 

Good luck.

 

Edited 1 February, 20251 yr by nta16
ETA: hopefully better reading(?)

I cold started the car, it ran for 2 minutes and then died (as usual), I opened up the carb and this was the amount of fuel in the bowl (marked by the red line).
Correct me if I'm wrong but this isn't enough fuel to run, right?
I already replaced the float and needle so the fuel pump is my next priority, maybe its not working properly when the engine is cold, @nta16 the electric one I have ordered should arrive in the next couple of days.
The weird thing is that I can see fuel being pulled from the gas tank through the clear plastic filter that is placed before the fuel pump, maybe its not pumping good enough when cold (I hope).

I do not know the carb at all so better for others to comment. if the read lines are those very small red lines then, to me it looks low but the float is very deep and depends what all those markings are about.