Weird problem with Solex / cold start

Well, I've been having lots of problems with cold starting since my Jeep's been up and running (I've posted a few threads about it). After checking and testing around, I finally realized that the new mechanical pump I bought was either draining back or losing prime while the Jeep was sitting...which created a situation the next day of taking FOREVER for the Jeep to start and stay running. I opted to switch the mechanical pump out for an electrical one, but I still have an issue. When the Solex carb sits, it seems as though the float or needle/seat is getting stuck, preventing the carb to fill up back up. When its cold, I can crank and crank the jeep, pump the pedal, and sometimes get it to fire for a second. If I get out while the key is on (pump running), I can gently tap the side of the carb with a mallet and you can actually hear the gas rush into the bowl. Once I do this, you can work the throttle and actually see the accelerator pump finally shooting gas down the carb. Then, the jeep will start and run fine.

Anyone else encounter this with a new Solex? Carb is only a few months old and everything is new on the motor. The thing runs great other than this. I'm about to pop the top of the float bowl when its cold and find out what's going on, but I wanted some input first from the Solex guys, cause this is annoying.

 

One thing when you pump the pedal all you will get is whays left in the carb.You should just turn over the engine and the fuel pump will get the gas to the carb if your not getting gas to the carb lines clogged or fuel pump is not working proper imo hope this helps some

 

my new solex seems to drain back past my also new fuel pump, but I haven't had any problems with starting. It usually only takes 2 attempts before it sputters and starts, then I don't have any further problems.

 

The instructions that came with my solex stated to "Not pump the
pedal". I pull the throttle knob out, switch on the electric fuel pump
for 5 seconds and it starts right up. After a minute or so, push the
throttle knob in about half way and after another minute or so, push
all the way in.. That is for a cold start. After it warms up to operating
temp., I don't use the knob again. I'm using an electric fuel pump with
about 2 lbs pressure.
So far I like the solex...

 

I would suggest pulling the top off like you said and ensure everything is aligned properly with the float but also with the valve in the top. There is also a screen filter on the intake of the carb. Possibly an obstruction if the electric pump does not have an internal filter like the mechanical ones.??
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I have had the same problem with my Solex. I'm learning from this thread on how to try to start up using just the choke, but I installed a one-way check valve inline between the carb and the mechanical fuel pump. I don't know yet if it'll solve the problem but it was the only fix I could think of.
W-

 

Sorry, I don't mean to hijack your thread here but I just bought a new Solex and was looking at it and I'm confused about how the choke works. There is no butterfly valve for the choke, I thought it was missing some parts until I read this from Glenn.

 

The Solex doesn't have a choke per se, but an enrichening circuit. They add lots more fuel instead of using less air and a little more fuel.

My Solex acts like everyone elses. After several days, have to crank and crank to get it to fire. But the enrichener doesn't require pumping the accelerator and if fires right up.

My Carter on the MB "welds" the needle and seat shut after it sits awhile. Usually I can bang on the top of the carb and it will start, but sometimes I have to pull the top off the carb and manually separate the two.