b. Clean the carburetor – pay close attention to the electronic choke area. 5. Scooter starts and idles fine but falls on its face when accelerating / scooter does not have good top end. a. The scooter could have one of a couple of potential problems. i Clogged carburetor . – check the jets! They are probably dirty. Just like others have said,I mainly believe it's how they refomulate the gas.From your fuel pump to the carburetor it seems it's evaporated and what's in your carburetor has evaporated too. My Camaro does it all the time with temperatures above 90 and with the Corvette it starts ok but the idle is off about 100rpms until it runs a few minutes but I've got an air gap intake on the Corvette. QuadraJet Idle Problem from corvetteforum.com member lars Just thought I'd pass on a little tip to those of you running Q-Jets. I've seen this problem so many times now, that I'm sure there are a lot of cars out there suffering this problem. This weekend, I was once again working on a guy's car that was suffering from eratic idle once warmed up, and the idle mixture screw on the passenger side ...
It is very easy to test the function of the accelerator pump. Start the engine, and warm to normal operating temperature. Shut off the engine. Remove the air cleaner. The choke butterfly should be fully open, as the engine is warm. Observe the pump jet in the carburetor, and with your hand, work the carburetor throttle to the wide-open position. If it still won't start, the problem could be the spark plug, fuel line or carburetor. See our DIY chainsaw repair page for symptoms and step-by-step repair instructions. 1. It's so basic, but it happens: make sure the On/Off switch is set to On when you start it. 2. Old fuel collects moisture, making the fuel difficult to ignite. The carburetor is the most common problem area in all small engines. The carburetor is where the fuel mixes with the air to be burnt. Carburetors are on almost all types of combustion engines. When an engine sits for a long period of time without being ran, the fuel will start to break down.
Fuel can also boil inside the carburetor due to missing gaskets, spacers, or heat shields. Also check to see if the exhaust heat riser is stuck, allowing excessive heat under the carburetor. #3 Excessive fuel pump pressure: Avoid extremes in fuel pressure. Aug 04, 2015 · Kick Starting an Old Four Stroke - A Millennial How To - Duration: 6:32. Hermit DaVlog 236,120 views Why carbs cause cold-start problems. By Ken Corkett Oct 28, 2011. Share this article: ... A non-hot start with a carburettor engine, normally after a drive on a hot day, and then sitting for a ... My 72 super beetle will not start when she's hot. When the weather is mild, she runs like a champion, but I live in CA in the central valley, so 6 plus months of the year, I can't drive anywhere during the day.
Aug 02, 2017 · (7) Carburetor adjustments . Any problems in the above areas can cause the following: (1) No start or hard starting – hot or cold (2) Rough engine idle and stalling (3) Hesitation on acceleration (4) Loss of power on acceleration and top speed (5) Engine to run uneven or surge edelbrock marine carburetor 1409 edelbrock marine carburetor 1409; edelbrock vacuum ports edelbrock vacuum ports; oldsmobile cylinder heads oldsmobile cylinder heads; 5.3 supercharger 5.3 supercharger; cam 350 chevy cam 350 chevy; chevy crate engine chevy crate engine; crate engines chevy crate engines chevy; crate engines ford crate engines ford
I have no particular problems with hot-starting, but if the weather is really hot as well as the engine, then the gasoline will evaporate in the carburetor and I also guess that the check valve function in the fuel pump allows the fuel to drain backwards.
The first step in understanding your carburetor and how it operates is to describe the throttle slide (or valve) openings. Breaking them down into sections will help later in diagnosing where the jetting problem is happening and thus what adjustments are in play at each throttle opening.
If you can't start after you are hot, then you may be flooding usually caused by playing the throttle while kicking. If flooded, turn your ignition and fuel off, open your throttle full and kick over three times to clear your cylinders.
Before adjusting the carburetors, verify that the following items have been checked for proper operation. Many suspected carburetion issues are actually caused by faults within the ignition system, making this the first place to look before making any carburetor adjustments. Why carbs cause cold-start problems. By Ken Corkett Oct 28, 2011. Share this article: ... A non-hot start with a carburettor engine, normally after a drive on a hot day, and then sitting for a ...
Re: Quadrajet hard starting when hot? definintely make sure the choke is all the way open when the motor is hot. Also, you may want to look at it (the choke) opening after you put power to the inginiton wires and the motor is warm, some of them open slowly and may take 5 to 10 seconds to open fully Author Topic: Mercruiser 140, starts when cold, won't start when hot? (Read 18364 times) (Read 18364 times) 0 Members and 1 Guest are viewing this topic. Removing the solenoid is the best way to test, that allows you see it actually open and close. If you have a power supply problem, use a dvom or test light to check for power. If the solenoid fails the mower won't start, and a failing solenoid will cause problems like, only working when it wants to, or shutting down the mower. While not often associated with a carburetor problem, an exhaust leak is often overlooked and can lead to off-idle hesitation and deceleration pops. The gaskets between the head pipes and the exhaust ports of the heads is a crush fit that will leak if the pipes are removed, reinstalled, or over/under torqued. Author Topic: Mercruiser 140, starts when cold, won't start when hot? (Read 18364 times) (Read 18364 times) 0 Members and 1 Guest are viewing this topic.
When starting cold, are you using the choke? If so, try using no choke. Still no start, try pulling the hot start (once fixed) and if it fires up, pilot circuit is to rich. Worst case, you say you have a 400EX with a TRX carb? Swap them and see if it helps, that will tell you if the problem is carb related. Just like others have said,I mainly believe it's how they refomulate the gas.From your fuel pump to the carburetor it seems it's evaporated and what's in your carburetor has evaporated too. My Camaro does it all the time with temperatures above 90 and with the Corvette it starts ok but the idle is off about 100rpms until it runs a few minutes but I've got an air gap intake on the Corvette.