Steve, putting all your video's togetherr, you almost build one of the best syllabuses in the world for car enthousastics. Now we have are cars back in the road again in all their glory, what's next? Race tuning? Suspension , stiffness, .. . Great video, in full detail, thx
As always end up learning so much from your videos. Also so refreshing not bugging viewers to like subscribe half way through the video. That comes naturally when talent and good content is recognized.
@@D3Sshooter It is a real problem on final approach with tightly cowled aircraft. You have to keep a little throttle on to keep the lines cleared or the engine will cut off. Also it is an issue when on the ground doing a quick turn around. You land pull into the local FBO and drop your passengers and then have to get back out start up with in 15 min. We would have to purge the lines with the boost pump hoping you do not blow a jug. Once you learned the procedure it was no big deal. You just had to be aware of it. I have lots of years flying lots of different aircraft. Jim
Thanks to you for the time and professionalism used in explaining the cause of the engine failure and what the solutions to the problem may be a greeting from the city of Catania
Thanks for the comments, Me too... but to be very honest , the , modern cars are not that much different, they are just more computerised. What I see with many young tech's is that they just follow flowcharts, read the ECU stored faults and start to replace parts untill its fixed. ( faut code gone). Often to many parts are replaced that way... They don't apply in many cases common sense and logic..sad
@@D3Sshooter Yes, we have an expression for that 'tactic' in America. We say the mechanic 'threw parts at the problem'. It obviously does not show very much diagnostic moxie. A common point of view in America is that mechanics of all stripes do not like cars older than about 1996, because that is when OBD2 came in. With OBD2, the computer tells you what it does not like. You replace that, and the computer is happy. Of course, there are other things, but the complex electronic stuff is thoroughly dependent on the computer telling the mechanic what the story is.
Another fine video, another great explanation of potemtial problems followed by very good solutions. I never had fuel evaporation issues with the Jaguar's I have owned but have with Series petrol Land Rover's and Triumph cars owned by the family as I grew up.
8:50 Looks like you need to replace your mounting studs with longer ones to make up for the spacer. 19:20 He is exactly right! Many, MANY DIY'ers think that the right thing to use here is "dielectric grease/compound" and they pass this error along to others. You are NOT trying to insulate or protect anything here; you are trying to transfer as much heat as possible.
Exposing electronics to heat is always a bad idea and should be avoided wherever possible, the Rover SD1 Vitesse V8 has the amp mounted on the bodywork, not the distributor, a much better idea. There are also lots of cars where the coil is mounted on the engine, equally insane. Anything which can be done to lower temperatures in the engine compartment is good, improved ventilation and exhaust manifold insulation come to mind. Your well informed and clearly presented videos are much appreciated, thank you sir.
Re: the ignition trigger circuit, I had a similar problem with my old '91 Dodge van. My mechanic replaced the distributor, the coil and the computer, and could not get it to work, so he returned it to me, still broken. (!) In my case, this was pre-OBD2, where the computer blinks a light on the dash in sequences to give you the code, and it complained about the distributor not giving any signal. Having the real shop manual, I rigged the distributor up with the 8 volts specified, and hooked the output to a scope, and spun it like you did, and it gave no pulses (from a remanufactured distributor)! So I replaced just the electronic part of the distributor and timed it and the engine ran again. My mechanic had no scope, nor the electrical savvy, and I have found that my local Dodge dealer is not very good at electrical stuff, either.
Thanks for the comments Dennis, That is very common for dealership / mechanics. They don't work anymore as we used to do at the time. Back to basics' test and diagnose, understand and fix... I have had new parts that were bad (like this new dstributor in the video).
Sheffield University did a lot of research on fuel vaporization on an XPG engine and in the end concluded that adding 5% of heating oil raised the boiling point of fuel high enough to prevent problems. However they also found considerable variation in ethanol content in 95 Octane fuels, but not in the 97 Super fuels, which they recommend. Power was not affected with their engine on their dyno.
As you observe Steve, the modern "fuel" that we have to run on is extremely volatile, this cause problems with the warm manifold/carb being at, or above the evaporation point of the fuel, tests carried our recently at Manchester University found that one way to overcome this problem was to add 5-10 % of kerosene to the fuel, this went some way to solving the problem, it does, of course reduce the octane rating , so can cause problems in high compression engines, quite why we have been inflicted with this modern rubbish fuel is a mystery, it causes vehicles to do much less miles per gallon, so can hardly be considered a "green" alternative to proper fuel, but no doubt it appears on a different chart as "better" for the environment, so ticks the right box as far as politicians are concerned, you know, the ones that jet off to exotic places for the weekend. Stay safe! Chris B.
Another great video. Your explanations are excellent. Have you made a video on classic car electrics?? Can imagine your presentation skills would make understanding electrics easy.
I had that problem with my 97 Volvo 850 which continued after replacing both the MASS Air flow sensor and the Engine Coolant Temperature sensor. What finally fixed it was replacing the Ignition Coil.
I have designed in the distant past but have been more involved in the core network hardware repair side (component level) of all the major manufactures..Cisco, 3com, Enterasys ...etc etc. My interests, although quite amateur compared with yourself, are also with home DIY and car maintenance so your channel just ticks all the boxes for me especially now you’ve got the ‘scope out :)
Shaun Cymru that is a coincidence. I am very busy with Cisco Asr’s and Nokia network designs based in SDN and Segment Routing IPv6. Seems we have a few things in common
D3Sshooter very impressive Steve, Cisco 9000 ASR,s are some high end core kit ..let me tell you they are a bit*h to fix lol...much prefer the 6000 or 4500 platform for repair!. You really are a man a many talents and on behalf of your community, would like to thank you for the effort you put into this channel and hope it gets some serious subscriber numbers it deserves. Thanks for commenting back Steve.
Really clear explanation. I just posted this question to another forum and was referred to this video. Have a similar problem on my 1976 TR6 with points. Starts up cold easily. Turn off when warm and restart immediately it starts up (like when your working on engine in your garage). Go for a ride and then park and wait for 15 min or so and it won't start start up. Sounds like its just about to catch though doesn't. Cool down and starts up. I have replaced plugs, wires, distributor cap, rotor, and added aluminum heat shield. No luck. Have adjusted timing, maximized vacuum by turning distributor. If it starts right up when you turn if off and then on though doesn't after it sat for 15 min after drive doesn't that point to a fuel vapor or percolation issue rather than an electrical issue?
Thanks for the comments, It could be fuel or ignition issues. And I can see your frustration with it. It can be very hard to find the issue. If you have points, then you will not get the issue with the amplifier. I would, if I was you run up the engine until warm. Stop it, then try to start. If its does not, take the HT lead coming from the Coil into the distributor cap out the cap. Plug a spark plug onto that HT lead and make sure there is ground to the sprak plug. Have someone to start the motor and see if you have a solid and good spark. IF that is OK, then you have a fuel of carburettor problem. Vapor look, or starvation. One way is to drop or spray some fuel into the intake manifold and try to start ( off course put the HR lead back). If the engine was suffering from starvation ( Vapour lock or so) it will fire-up with that sprayed/injected fuel. If it does not start, then you have an issue with flooding, try to look into the intake manifold through the carbs by lifting the floats ( I assume is a stromberg or SU) and see if the intake manifold is wet. If that is the case , the engine suffers from flooding.... that is fuel pressure , float levels . Its a long process to find it, but you will. There is one last possible issue and that is ice-ing. sounds strange , I know. But fuel when evaporating cools the surroundings and its not uncommon in very damp / high humidity environments that ice is formed around the jets... And there is one last one, and that is valve clearance. If that is set wrong , it can be that the valves don't close entirely when hot. That would make a cold start hard.... I hope that this helped a bit, Steve
Very good video. I have a Renault van on diesel with a brand new engine (bought from Renault factory two months ago). Last week it started this warm engine issue. I have to mention I hear one click after I turn the key. Could that be an indicator of the cause? Thanks!
Hi loved the video, I have two questions I have a similar setup for a range rover classic , two questions: I need the part number for the lucas amplifier also how did you setup your return line I have the same carb and regulator. Thanks Ole
On the ignition coil: small correction. It reads 1.6 ohms, which becomes 1.3 after subtracting the lead resistance, which is good. You called it at 2.6 becoming 2.3 ohms.
A very good video 👍. One question: in a returnless fuel system, how is the vapor lock issue solved by design please? My car is having warm start issue, but I don’t see any special device on the fuel rail, except a fuel pressure sensor (with a vacuum hose connection). How vapor can be purged in such a dead-end system please? Thanks!
Fuel lines located too close to exhaust system commonly causes this. Move or Insulate the lines. Or insulate the exhaust pipe or header causing the problem.
Could vapor lock be an issue on a 1988 carburettor car? I've tried everything in the ignition system but it's not fixed the hot start problem. Changed spark plugs, ht leads, ignition coil and I've been assured everything that could be replaced in the distributor has been changed. Still won't start when hot.
It might , or its flooding... Both are an issue... If you have an electronic ignition , that might also be an issue when its hot. I had that once on the MGB GT V8
Used to have that problem vapor lock on high hp motors we used to install a aluminum plate between carb and manifold ..then use electric fuel pump with braided fuel lines with a return to gas tank..
My 2017 Lexus LS460 will not start or have trouble starting when the AIR TEMPERATURE is hot outside, usually about 80 degrees Fahrenheit and above. It's quite annoying and the dealer said it's not the battery and they frankly do not know what it is. It seems to happen most with hot weather when the car has been sitting in direct sun. After a minute or so of trying to start the car it usually starts. Any ideas?
Thanks for this video. I have same problem with my Audi a6 from 2007. it starts fine when it is cold but when I drive and turn off the engine the car does not start immediately but has to wait like 3 minutes then it starts again. I dont know whats the problem problem yet:-(
Thankyou so much - Your videos are absolutely brilliant for a novice like me trying to figure it all out. My 1977 Camaro (inline 6) is not happy after warm starts - it starts fine from warm but the idle is always very low and weak after a warm start - then the car hesitates and stumbles under load for the first mile or so but then it runs absolutely fine when back up to operating temp. Could this be a symptom of vapour lock ? The car has recently been fitted with an electric fuel pump which has made a huge improvement and carb has been fully rebuilt along with new distributer and coil and fuel filter. It runs beautifully from cold and runs fine when up to operating temperature but it just always seems grouchy and hesitant when the engine is started from lukewarm and has been sat for an hour or 2.
Sorry for the late reply , as i was away for work. But thanks for the comments. I would think that yours suffers from flooding.. have a look after a ride ( warm/hot engine) and look inside the carb ( engine turned off). There should be no dripping of fuel. If you do see dripping inside the carb ( you need to look down into it) then you have a flooding issue
I have the same exact issue with a 350 and a holly carb. Runs fine from a cold start but as soon as i shut it off for more than 30 minutes it wants to die upon startup. I actually have an AFR gauge installed and when this happens the mixture is reading EXTREMELY lean, like up in 19-20’s. It’s heat soak. Our carbs are sitting under the hood in basically an oven so when we try to fire it up again it’s trying to use all the heat soaked gas and vapor left in our carborator. So until that old mixture is blown out of the carburetor and replaced with fresh fuel from the tank it’s running lean and “grouchy”. I need to get a good phenolic spacer for my carb because the body gets super hot and I’m 99% sure my fuel is getting way to hot
Thanks so much for your reply - I’ll have a look next time after a drive and see if there is any dripping in the carb. It’s also developed another weird habit lately where occasionally it will sputter and nearly cut out when I take a sharp right corner at slow speeds. When it does this I get a strong smell of fuel so I’m thinking your most likey right in that it is a flooding issue
Bone Thang - it certainly sounds like yours is mirroring the same symptoms as mine. mine does smell quite rich at times though so I’m not sure if it’s a lean condition.
Good day, I have a 98 Nissan Sentra. I just have a quick question. My car doesn't want to start but has spark. However, I have a mechanical fuel pump which I only put on a few months ago and already no fuel seems to be coming through. Could it be due to my carburetor being bad or should the pump still have pushed fuel through to the carburetor. I think I might have an aftermarket pump.
Well it seems that you might have a clogged fuel line or dirty fuel-filter, try to remove the fuel tank cap and take off the hose on the fuel-pump that comes from the fuel tank and blow compressed air into the hose. You should here the air bubbels in the Fuel thank. If not then you have a clogged tank or fuel line...
I have the same issue with my Nissan patrol tb42s engine it appeared after I changed my carburetor to an aftermarket China made type An easy way to solve this issue without changing anything is to keep wide open throttle when starting the car
Hey Steve I have a 2003 Chevy Silverado with a 4.8 engine I’m having this problem rn I changed the fuel pump,fuel pressure regulator,fuel injectors,spark plugs and I have performance coils and this only happens when my engine is hot and in the mornings it turns on perfect any help I would appreciate it
Hi, so this car i shaving an injection and is not naturally aspirated. Based on what I read, you have changed and inspected most parts. I suspect that you have sensor issue, such as the MAP, MAF ,MAT etc Those measure the condition of the engine state in terms of manifold pressure, temperature , airflow and other. I would first connect a OBD2 scanner and see what faults are logged by your ECU. If you have none logged or pending, scan the live data with a running engine and check the values.... Its hard to stated what it exactly is by the information provided... But at least this is a good start. You might also have a bad ground, make sure that the engine and injectors are all having a good ground ( - Battery)
I was dying to understand how old car carburated engine was really working withought computer, but i didnt know what they called it at first, i was srarchimg using old engine key word and that didnt get me what i need, that impressive, everything is mechanical. And the important part is the carburator that regulate the fuel/air mixture. In a comoutirised car, the computer do that by using sensors.
Hello, I have a problem with a bmw e60 model 2010. When I walk up hill for about an hour, after stopping and turning off the engine for a few minutes, I can't restart the engine and I have to wait about an hour for the engine to succeed again, please advise me
I have Audi TT 3.2 2009 model When the car is parked under shade it starts normal but when the car is parked under sun heat it do not start or starts after long cranks
Sir, I have an old carburetted car here in India. It has the same problem of not starting when hot.Nobody here seems to know what the problem is. Is there a Email address that I can get to further discuss it at length with you?
Hi this is a perfect video....i have similar problem with my fathers car... it's a mitsubishi l300 van model 1982 with 4g33 engine 1.4 cc carburator.so here is what happens.when it is cold it fires up immediately (what a perfect feeling).then when i go for a drive and the car reaches the operating temperature and come to home and let it for about 45min to 1 hour and started to fire it ......then it hesitates to start and starts after 5 to 7 cranks simultaneously.....then if i turned it off and immediately start it again it fires up perfect.....what should be? I change the carb with new one i put new sparg plugs with new sparks put new mechanical fuel pump .put another ignition coil (but a used one that said to me that is ok) the problem exist.... ,🙄🙄🙄🙄🙄🙄what must I look....i m very confused....seems not to be vapor lock or heat perculation...i m not sure what to do.....maybe new ignition coil???? I m looking for the amplifier u said but i m trying to locate it in my car.......any ideas i will try to post photos.
Hmm maybe i found the problem...i saw that my mechanical fuel pump isn't the correct one.doesnt have 3ports which one is the return line.someone put a pump with 2 ports snd the return line is bloked....so it is possible that thing makes heat percolation....i will put the correct one and then try again
Could be several things, you will need to test it by removing hoses while it has the issue, maybe spray some gas into the intake manifold, test the ignition with a sparklug out of the engine... etc... I wrote a complete part on that in one of the comments.
@@D3Sshooter i m very desperate...i thought i found the problem but.....no..... I was thinking that must be a fuel problem but I fail. I have put 3different carbs and the symptom is always the same.so back to ignition...i change sparks spark plugs new coil ......the same thing.....the only that remains is to test the distributor....any ideas how to figure how? Do u think that a distributor will make that problem i have described above be solve?
There a RU-vid where they do Off Road recoveries in the desert where over 100 is normal. I saw one where a jeep with fuel injection wouldn't start and they poured cold water on the fuel rails and it started right up, He said they used the same trick on carbureted cars pouring water on the carburetor to cool it down
