Why would I ever follow courses on car mechanics when there are more detailed videos available on your channel! Another masterpiece on how clear pragmatic instruction video should be.
I Really enjoyed this video. You concentrated a lot on "flooding" I have a 78 MGB GT and when she is up to temp and I switch off, as you said in your video "bloody impossible" to restart. Most people on forums are telling me that "vaporisation" is the number one culprit, but i do not know how to sort. I am not a mechanic but i can do general serviceable things and have a decent automotive knowledge. The are twin HS Carbs. Thanks in advance
The main thing is to get the heat away from carbs. By using a shield of some sort.... there are several methods for this... of course if the issue is vapor
Fantástic!!!! I sometimes i see a drip in one choke of my 40 dcoe. Its not all the time , but sometimes it hapens. Only in one choke of the same carb. Changed the washer, cheked the fuel level.and everything is ok. After changing the return fuel jet from 50 to 60 it got better. Idles 20 minutes and no driping. While driving i canot see..... Thanks for your videos... You are the best sir!!! Cheers from Portugal
This could be the most informative video out there. Great troubleshooting, and simple explanation process. Thank you for sharing your experience, this video helped A LOT.👍
Great information, thanks for sharing. I am troubleshooting my 1977 Ford F150, It starts up, when cold in morning, after barely turning igniton with a little finesse with the pedal. After a drive for 15 or 20 minutes, and go to store or gas up. I takes a couple long cranks. I have rebuilt the carburetor a long time ago, it ran great for only a year or so. The symptoms are of heat soak or flooding. I might have a combination of the two. I also noticed after driving and warm, it WILL start up right away after I turn it off. If I wait 5 minutes or so it has trouple starting, which stresses the starter, definitley need to fix, no fun to deal with. I like the tip about the float needle valve and seal. Im still learning about this old truck.
You should add that if you replace your mechanical fuel pump with an electrical pump that not only should you have a pressure regulator but also a cut off switch that activates in the event of an accident.
Thank you for the comments, yes indeed that is an absolute must. Off course this video was about flooding and Vapour lock so I did not cover electrical fuelpump installations.
Great video as usual. I have a similar car to your DAX and years ago had a vapour lock problem (Australian summers get quite hot). The front mounted pressure regulated fuel pump (expensive American brand) would go crazy trying to pump vapour instead of petrol. I mounted the fuel pump at the rear next to the fuel tank and had no more problems. The fuel being under pressure no longer vapourises. Rear mounted pumps are different to front mounted pumps (eg Morris Minor front is different to a Mini rear). It must have something to do with the size of the valves or the stroke. No more standing alongside the car in 40deg celcius trying to squirt water on the fuel line. Best wishes and stay safe
Other problem with flooding is oil dilution, bore washing & in severe cases risk of hydro lock during cranking. Certain carbs are way more prone to floats sticking / not shutting off correctly particularly after being stood empty for a while. Never had vapour lock but have had carb icing which is at lower temps but also gives a fuel starvation issue which self heals as the ice melts!
One item you didn't mention was fuel frothing. Not so much an issue with most factory installs but many aftermarket setups bolt the carbs solid to the inlet manifold which can result in fuel being vibrated in the float bowls, fuel frothing & subsiquent overflowing / flooding. There are flexible elements (basically a bonded gasket which seals without being clamped solidly) which fit between the manifold & carb to reduce the vibration transmission into the carbs which can eliminate the problem.
You can also get flooding with Weber carburettors from vibration affecting the float. This occurs if you don't have isolated mounts to the inlet manifold or you over tighten the isolation mounts.
Fuel pressure and volume can also be a cause in vapor lock issues as well. If the fuel pump is getting weak, the pressure of the fuel can drop to the point that vapor can too easily separate from the fuel when it heats up in the lines. I experienced this when I was much younger on an old Dodge Coronet I had. Had vapor lock issues usually while in traffic in warmer weather. Replaced the original mechanical pump with a new one and the problem disappeared.....
Very helpful and informative. Just to make sure, so if my engine starts to acting up only when the engine is warm then stalls, and there’s no power on accel., then i check the main jet and finds no drip, i have a vapor-lock/starvation problem? Did i got that right?. And if my logic was right, if the fuel pump is getting weak, it could cause a fuel starvation right? Sorry if i asked too much, I’m only 19 and trying to get the hang of it, anyways thank you very much.
Your explanation is just the right way, scientific approach, just like we do in medicine. We first understand the normal physiology, detect the abnormality (symptoms), analyse them and come up with a diagnosis and eventualy a plan to treat. In one word magnificent. My Alfa spider has a double solex carb and it floods. Curious thing is that the dripping contineus even after stopping the engine and the fuel chamber wil be empty which gives a headache starting the car the next time. I am not understanding the abnormality causing contineuos dripping till empty!? any thoughts? kind regards Paul
Sorry for the late reply , as i was away for work. But thanks for the comments. Well you have what we call flooding, there are a few things that can cause this " wrong float level - to high" , to high pressure of the fuel pump ( note that the pressure remains for a while after the engine is stopped) and or a fault needle valve
At the end of your vidio you could have turned the fuel tap off after you shut the motor off to see How long the pressure remained on the gauge. Could save taking the carb off for testing.
Very profesional videos! I have Weber 48 IDA. planing to rebuild it, also had flooding problems caused by wrong float possition. Fixed, later found that pump jets have worn out O rings, which looks like causing fuel to overcome pump jets. So ended with full rebuild. When are you planing to release Weber dcoe 3 part - tuning? Are you planing t
hello greetings from greece your videos is really helpfull i wanna ask about something i have a bike with a keihin cvk carburator as the years pass the bike start to not have much power as the older days also the bike burn a lot more gas i open it and i clean the pilot jet and the main jet but nothing is changed the bike still lacks of power and fuel efficiency any thoughs?
I never had vapor lock until fuel was mixed with vodka (ethanol). So not only does this fuel cocktail absorb water vapor from the atmosphere, ruining old rubber components and causing rust, but it boils at a lower temperature leading to vapor lock. Modern cars have a sealed fuel system and high fuel pressure to mitigate these drivability issues. Old cars and even modern lawn/garden equipment react badly to ethanol/gas mixes. !00% gas/petrol, high octane, is now becoming more available in my area, although at a high price.
Changing the gas has always been my go-to thing to check after checking that there is oil and the air filter isn't clogged. Small engines and ethanol are a bad couple.
Thank you for the comments jak, indeed the addition of ethanol to gasoline has created a mixture with a lower boiling point, so gasses form much faster besides the fact that the methanol affects other parts
I think the hydroscopic nature of ethanol (ie. its ability to absorb water) strikes a double blow for classic cars because they tend to do low mileage and maybe don't get used at all over winter. Do you fill up the tank so there is less moisture filled air and less chance of condensation, or put in a minimum amount and refuel regularly to keep the fuel fresh?
I saw that different types of Dcoe.s have different fuel levels. I wondering if that the level is the same, no matter the type of Dcoe, if I measure by caliper (29mm)? Thx
How can I email you? I am having trouble with a pair of solex c40 addhe carbs and I’ve watched all your videos to get it close to running correctly but no luck in getting it tuned right. I would really appreciate the help sir! Great video by the way!
Triple 45s italian..Would float levels and/or faulty valve cause immediate 3.5 psi pressure at startup, with beautiful idle for about 5 min then rapid decrease to no pressure and stall? Help me D3Shooter!
Thanks for the comments, No it would not in full. There are three things at play here. 1.) Yes an electrical fuel pump prevents vapour lock as the pump is far away from the hot engine, so no vapour build up in the pump 2.) increased fuel pressure allows a higher boiling temperature, thus less vapour forming, however pressure needs to be regulated. 3.) as pressure into the carb, needs to be adjusted to the level of acceptation (for the carb), the initial higher pressure is not going to help as it needs to be regulated to a lower pressure.
Best Carburetor instruction on YT or in print. Well Done! Thank you!
Why would I ever follow courses on car mechanics when there are more detailed videos available on your channel! Another masterpiece on how clear pragmatic instruction video should be.
Wow, thanks!
I Really enjoyed this video. You concentrated a lot on "flooding" I have a 78 MGB GT and when she is up to temp and I switch off, as you said in your video "bloody impossible" to restart. Most people on forums are telling me that "vaporisation" is the number one culprit, but i do not know how to sort. I am not a mechanic but i can do general serviceable things and have a decent automotive knowledge. The are twin HS Carbs. Thanks in advance
The main thing is to get the heat away from carbs. By using a shield of some sort.... there are several methods for this... of course if the issue is vapor
Not only are your tutorials excellent your video production is first class 👍
Glad you like them!
I learned a ton from this video. Figured out my carburetor is flooding.
Thanks for the comments, good to hear
Fantástic!!!! I sometimes i see a drip in one choke of my 40 dcoe. Its not all the time , but sometimes it hapens. Only in one choke of the same carb.
Changed the washer, cheked the fuel level.and everything is ok.
After changing the return fuel jet from 50 to 60 it got better.
Idles 20 minutes and no driping.
While driving i canot see.....
Thanks for your videos... You are the best sir!!!
Cheers from Portugal
Thanks for the comments
This could be the most informative video out there. Great troubleshooting, and simple explanation process. Thank you for sharing your experience, this video helped A LOT.👍
Great information, thanks for sharing. I am troubleshooting my 1977 Ford F150, It starts up, when cold in morning, after barely turning igniton with a little finesse with the pedal. After a drive for 15 or 20 minutes, and go to store or gas up. I takes a couple long cranks. I have rebuilt the carburetor a long time ago, it ran great for only a year or so. The symptoms are of heat soak or flooding. I might have a combination of the two. I also noticed after driving and warm, it WILL start up right away after I turn it off. If I wait 5 minutes or so it has trouple starting, which stresses the starter, definitley need to fix, no fun to deal with. I like the tip about the float needle valve and seal. Im still learning about this old truck.
Thanks for the comments and write up.. Good luck
Thank you for taking the time to explain all of this. I appreciate your videos, they're very thorough and informative for each step in the process.
You're very welcome!
You should add that if you replace your mechanical fuel pump with an electrical pump that not only should you have a pressure regulator but also a cut off switch that activates in the event of an accident.
Thank you for the comments, yes indeed that is an absolute must. Off course this video was about flooding and Vapour lock so I did not cover electrical fuelpump installations.
Good details & explanations nice work 😊
you have exceptionally high-quality videos! thank you for the time and effort put into making them!
I appreciate that!
Great video as usual. I have a similar car to your DAX and years ago had a vapour lock problem (Australian summers get quite hot). The front mounted pressure regulated fuel pump (expensive American brand) would go crazy trying to pump vapour instead of petrol. I mounted the fuel pump at the rear next to the fuel tank and had no more problems. The fuel being under pressure no longer vapourises. Rear mounted pumps are different to front mounted pumps (eg Morris Minor front is different to a Mini rear). It must have something to do with the size of the valves or the stroke.
No more standing alongside the car in 40deg celcius trying to squirt water on the fuel line.
Best wishes and stay safe
Thanks for the comments and the great write-up.
A methodical approach , as always. Thank you!
Glad you liked it!
Other problem with flooding is oil dilution, bore washing & in severe cases risk of hydro lock during cranking. Certain carbs are way more prone to floats sticking / not shutting off correctly particularly after being stood empty for a while. Never had vapour lock but have had carb icing which is at lower temps but also gives a fuel starvation issue which self heals as the ice melts!
very good points
Outstanding as usual sir😎going to tear down my Chinese Weber 38/38 dges next week. Thanks for the through instructional videos.
Thanks for the comments
Really helpful tutorial, many thanks
One item you didn't mention was fuel frothing. Not so much an issue with most factory installs but many aftermarket setups bolt the carbs solid to the inlet manifold which can result in fuel being vibrated in the float bowls, fuel frothing & subsiquent overflowing / flooding. There are flexible elements (basically a bonded gasket which seals without being clamped solidly) which fit between the manifold & carb to reduce the vibration transmission into the carbs which can eliminate the problem.
Thanks for the comments and very good point... that is another aspect
Thank you so much for taking the time to share this information. really good quality video
Thank you
You can also get flooding with Weber carburettors from vibration affecting the float. This occurs if you don't have isolated mounts to the inlet manifold or you over tighten the isolation mounts.
Thanks for the comments and yes indeed...
I think i had that problema in One kg my Pump jet.... One sometimes was leaking during idle....
Fuel pressure and volume can also be a cause in vapor lock issues as well. If the fuel pump is getting weak, the pressure of the fuel can drop to the point that vapor can too easily separate from the fuel when it heats up in the lines. I experienced this when I was much younger on an old Dodge Coronet I had. Had vapor lock issues usually while in traffic in warmer weather. Replaced the original mechanical pump with a new one and the problem disappeared.....
Thank you for the comments John, and indeed higher pressures lower the boiling temperatures of liquids. That is indeed a cause for vapour lock.
Very helpful and informative.
Just to make sure, so if my engine starts to acting up only when the engine is warm then stalls, and there’s no power on accel., then i check the main jet and finds no drip, i have a vapor-lock/starvation problem? Did i got that right?. And if my logic was right, if the fuel pump is getting weak, it could cause a fuel starvation right?
Sorry if i asked too much, I’m only 19 and trying to get the hang of it, anyways thank you very much.
Thanks for the comments , indeed that is correct. Off course your engine should have no other issues like ignition and compression/ valve issues
Great, in-depth video. Thank you.
very clear carburetor troubleshooter!
Thanks for the comments
Your explanation is just the right way, scientific approach, just like we do in medicine. We first understand the normal physiology, detect the abnormality (symptoms), analyse them and come up with a diagnosis and eventualy a plan to treat.
In one word magnificent.
My Alfa spider has a double solex carb and it floods.
Curious thing is that the dripping contineus even after stopping the engine and the fuel chamber wil be empty which gives a headache starting the car the next time.
I am not understanding the abnormality causing contineuos dripping till empty!?
any thoughts?
kind regards
Paul
Sorry for the late reply , as i was away for work. But thanks for the comments. Well you have what we call flooding, there are a few things that can cause this " wrong float level - to high" , to high pressure of the fuel pump ( note that the pressure remains for a while after the engine is stopped) and or a fault needle valve
Great video dear Sir !!!
Thank you very much for this video.
thanks i got lost, will watch again , until i understand
Thank you for the comments, sorry maybe I went to fast ?
@@D3Sshooter i heard each word, just me,
my mind is to slow, ha ha
At the end of your vidio you could have turned the fuel tap off after you shut the motor off to see How long the pressure remained on the gauge. Could save taking the carb off for testing.
Thanks for the comments , indeed
Very profesional videos! I have Weber 48 IDA. planing to rebuild it, also had flooding problems caused by wrong float possition. Fixed, later found that pump jets have worn out O rings, which looks like causing fuel to overcome pump jets. So ended with full rebuild.
When are you planing to release Weber dcoe 3 part - tuning?
Are you planing t
Thanks for the comments, I would think in a month or so,,,,
An excellent Video, well done!
Thank you a lot maestro.
My pleasure
hello greetings from greece your videos is really helpfull i wanna ask about something i have a bike with a keihin cvk carburator as the years pass the bike start to not have much power as the older days also the bike burn a lot more gas i open it and i clean the pilot jet and the main jet but nothing is changed the bike still lacks of power and fuel efficiency any thoughs?
I never had vapor lock until fuel was mixed with vodka (ethanol). So not only does this fuel cocktail absorb water vapor from the atmosphere, ruining old rubber components and causing rust, but it boils at a lower temperature leading to vapor lock. Modern cars have a sealed fuel system and high fuel pressure to mitigate these drivability issues. Old cars and even modern lawn/garden equipment react badly to ethanol/gas mixes. !00% gas/petrol, high octane, is now becoming more available in my area, although at a high price.
Changing the gas has always been my go-to thing to check after checking that there is oil and the air filter isn't clogged. Small engines and ethanol are a bad couple.
Thank you for the comments jak, indeed the addition of ethanol to gasoline has created a mixture with a lower boiling point, so gasses form much faster besides the fact that the methanol affects other parts
@@bejoe6 Indeed
I think the hydroscopic nature of ethanol (ie. its ability to absorb water) strikes a double blow for classic cars because they tend to do low mileage and maybe don't get used at all over winter. Do you fill up the tank so there is less moisture filled air and less chance of condensation, or put in a minimum amount and refuel regularly to keep the fuel fresh?
Ahh finally, the wait is over...Let me get my notepad to hand 😃
Thank you for the comments
You're right about taking notes.
I saw that different types of Dcoe.s have different fuel levels. I wondering if that the level is the same, no matter the type of Dcoe, if I measure by caliper (29mm)? Thx
Thank you, very clear an d very usefully.
Glad it was helpful!
How can I email you? I am having trouble with a pair of solex c40 addhe carbs and I’ve watched all your videos to get it close to running correctly but no luck in getting it tuned right. I would really appreciate the help sir! Great video by the way!
steve@flashsplash.be
Great information. 👍
Glad you think so!
1 question, when does the return come into play?
The return is always a good feedback mechanism as it keeps fuel circling and as such cools it
Goed verhaal!
Thanks for the comments
Triple 45s italian..Would float levels and/or faulty valve cause immediate 3.5 psi pressure at startup, with beautiful idle for about 5 min then rapid decrease to no pressure and stall? Help me D3Shooter!
Is there a link to the vapor lock video?
Thanks for the comments , yes ua-cam.com/video/tu6F_8jYlFk/v-deo.html
Wouldn't an electric fuel pump cure vapor lock?
Thanks for the comments, No it would not in full. There are three things at play here. 1.) Yes an electrical fuel pump prevents vapour lock as the pump is far away from the hot engine, so no vapour build up in the pump 2.) increased fuel pressure allows a higher boiling temperature, thus less vapour forming, however pressure needs to be regulated. 3.) as pressure into the carb, needs to be adjusted to the level of acceptation (for the carb), the initial higher pressure is not going to help as it needs to be regulated to a lower pressure.
👍
Lĺó
Thanks for the comments