Hot start problem

[67mutt]

Any one else have, or had one that is difficult to start hot? Mine fires up instantly when cold in the morning, no choke at all, and runs very well. When it gets up to operating temp. and is shut off, it is difficult to start. You usually have to crank it at least twice, and on the second try, If you crank it a few revolutions and then push the accelerator down about half way, it will usually start. Usually! Sometimes you think the batteries aren't going to make it, but it finally starts. I've tried it with and without choke. Its been this way as long as I've owned it. Could this be modern gas, or something else? It has, new module, wires, plugs, fuel pump, re-built Zenith carb.I've skipped over the coil because I've heard the replacements aren't reliable,and I think this one is O.K. ...HELP !!!

[rickf]

When you start it hot there are two ways of doing it.One or the other will always work. Try not touching the gas pedal at all, just hit the starter and after it kicks over then hit the gas. Try that a few times. If that method does not work then try pushing down the gas pedal about 1/4 and then crank it. That is what works on mine. Just so you know, pumping the gas pedal before you start does nothing at all. The vacuum operated accelerator pump will not work when it is not running.

Rick

[czechnology]

Do you have an A2 or an A1? Try to take out the hose from air filter to the carb (when warm) and check if there is any excessive gas in the hose. There should be nothing. If yes - then you have gas level too highly adjusted in the carb. As the carb is so close and unshielded to the exhaust manifold and pipe the hot temperature evaporates the gas inside the carb in just a few seconds, and the gas evaporates and stays in the air intake hose where it coagulates again. When you try to crank, the engine gets air extremely rich in gas fumes, and of course it won´t start. This effect is even worse with A1 because it does not have return line from the carb back to the tank. Solutions is simple - remove the carb and adjust the gas level in the float chamber accordingly. Good luck.

[rickf]

Do you have an A2 or an A1? Try to take out the hose from air filter to the carb (when warm) and check if there is any excessive gas in the hose. There should be nothing. If yes - then you have gas level too highly adjusted in the carb. As the carb is so close and unshielded to the exhaust manifold and pipe the hot temperature evaporates the gas inside the carb in just a few seconds, and the gas evaporates and stays in the air intake hose where it coagulates again. When you try to crank, the engine gets air extremely rich in gas fumes, and of course it won´t start. This effect is even worse with A1 because it does not have return line from the carb back to the tank. Solutions is simple - remove the carb and adjust the gas level in the float chamber accordingly. Good luck.

Czechnology, I have to take exception to what you say here. There will ALWAYS be some gas in the intake hose because of the vacuum operated accelerator pump. When the engine shuts down the pump puts out a squirt of gas as the vacuum drops off. That is what helps the cold restart and sometimes hinders the hot restart. That is why I always tell people to have the hose hooked up to the air cleaner whenever working on the engine. You have to have the the real world restrictions and carburetor quirks when tuning it up.

Rick

[67mutt]

Just for the record, It is an -A1. So the hot start problem is somewhat "normal"? I have recently been starting it hot with the accelerator to the floor, and it seems to start a little better. It is equipped with a glass sediment bowl, and I've not found any air bubbles in it, and its clean. So maybe I'll have to investigate my air cleaner and see if it's restricted, preventing proper ventilation. Any recomendations on cleaning the "horse hair" element? Last time I cleaned it I just carefully hand washed it with dish soap and cold water. It hasn't gone many miles since then, and runs very well, once started, so maybe its not even a problem. Heck, I dunno! Btw, anyone know who has a fuel hose with fittings on both ends? Mine is starting to show some age.

[rickf]

Just like any old car these can be temperamental. They all start differently so you have to try different things. Once you hit on the right combination you will never have trouble again. I have no idea how old you are but I have seen a lot of people that never driven a carbureted car have problem with starting because they are used to just turning the key and the computer does all the work.


Rick

[67mutt]

I'm 52 yrs. And I do miss points, plugs, and carbs. Sometimes cranky, but much simpler, and easier to work on.

[czechnology]

Rickf: Okay - they may be a little - but not much of the gas in the hose. I suspect this is gas lever in float chamber too highly adjusted, been there done that...

[67mutt]

I will check the float level. I absolutly trust your judgement. Thanks to all who replied. The wealth of knowledge here is incredible.