Why does a gasoline overflow occur in the bicycle?




 Float level
SimsonSR1


Advanced Member


Group: members
Posts: 146
Membership number: 718
Member since: 07/22/2007



Hello dear Essi friends,

I recently bought the book "Simson-Mopeds" by Erhard Werner. I think this book is really great, of course, all special problems cannot be dealt with, of course, but that's what the forum is for!
I had the problem that my float needle valve was leaking; sometimes it worked, sometimes the carburetor overflowed. So I bought a new one from "S ******* d" for € 10. I screwed it in and took a test drive, after a few 100 meters the engine started to stutter and went out.
After actuating the "tipper", the engine started again immediately, but ran again only for a short while. When I got back home with "oh and no noise", I noticed that the float needle valve wasn't 100% the same. In the said book I read how to set the float level correctly, there it was also reported that the engine can be seriously damaged by a "gasoline hit" if the carburetor overflows. Newer carburettors have a hole for the petrol overflow. With older ones
The author strongly recommends carburetors to make this hole later.
According to the author, I made an "adjustment device" from an old syringe and a brass sleeve. It is not perfect, there is no way to drain the fuel. But I was able to set the swimmer
the rest will be improved ...
Now my question to the professionals: What do you think of the subsequent drilling for
Gasoline overflow, did you ever have the case that the crankcase is full of fuel
ran? And: do you set the correct fuel level by bending the stop tongue of the float on the needle valve or can you put different thin washers under the needle valve? (If the fuel level is too low and for fine adjustment)

Many greetings Heiko

Attached image


--------------------
The longer here, the later there.
the Lehmann


Advanced Member


Group: moderator
Posts: 8548
Membership number: 487
Member since: 02/17/2007



Hello Heiko,

the fastest option for setting is the option with the measurement, already described by Norbert. I have put the photo here that I already presented with my conversion instructions. Look here

There are three basic types of carburetors, which differ from one another in terms of structure and setting. With the NKJ 121-01 (-1) and 122-4, for example, a seal belongs under the valve, with the 123-4 not. This is of course crucial for the setting. The setting is always made via the flexible metal tab on the float. The exception here is type 121. There is nothing on it to bend. You could use the washer method here.

Werner's recommendation is to be taken seriously. The overflow holes on the NKJ are all higher than the intake duct. If the fuel tap and the valve are not tight here, a disaster can occur. That must have happened more often in the past, otherwise the conversion recommendation would not have gone out to the workshops. To be on the safe side, I made this hole everywhere in my carburetors.

Many greetings, Jürgen

Attached image


--------------------
Many greetings, Jürgen

Participation UT 1 to UT 6 and UT 8 to UT 13
UT 14 in Saxon Switzerland also canceled in 2021!

"The ability is the measure of the may!" Paul Preuss
SimsonSR1


Advanced Member


Group: members
Posts: 146
Membership number: 718
Member since: 07/22/2007



Dear community,

Thank you for your answers, we can really rely on you. Otherwise I wouldn't know anyone around here to talk shop. When I did my first test drives with my Essis (in the meantime I have built an SR2 out of the fun of it), the local Westphalians opened their eyes like drumsticks ....
So Norbert, the bottle of "Jever" can hardly be seen, nevertheless you discovered it and "caught" me. I usually like to drink Wernesgrüner, but I always wondered where you get your in-depth knowledge from. I thought the "Jever" was, so to speak, the "drink of wisdom". So I drank a box, but it didn't really get me anywhere, your expertise has to come from somewhere else !? So, it has to be fun

many greetings and see you soon Heiko!


--------------------
The longer here, the later there.
Topic is being read by 0 user (s) (0 guests and 0 anonymous users)