2 Stroke Carb

[KE4AVB]

Correct.

[lefty]

Thanks. Knowing feels better than fixing. Is that weird?

[Fulltilt]

So let me try to understand. I'm guessing that because I can clearly see the movement of fuel through the lines when I pump the primer that the check valve there is working in at least one direction. And the fact that I don't see it flow in the opposite direction when I release the bulb that the valve is working, at least preliminarily speaking.

On the fuel supply side, if I'm not mistaken, the diaphragm acts as the valve? So with the carb disassembled, I should not meet any resistance on that side?

Forgive me if I'm off base here.

Well, bud, it seems that you didn't bother to read the link that avb gave you, no? http://www.zamacarb.com/page/carburetor-systems-operations
If you did, you would have a much better understanding of how the carb functions as a whole and how the individual systems contained in that little cube work, right?
I was going to link you to the walbro info,( pretty much the same stuff) but why bother... it seems you don't read it anyways.

As an aside...it seems some other people should read ( and understand ) the Zama info too.

[lefty]

Fulltilt

I'm not sure what about my post suggested to you that I didn't read that link. And since I'm new at this and did read the info in the link but maybe find it slightly challenging to wrap my head around, it appears you're just calling me stupid.

But having slightly more knowledge in human interaction than in engines, and observing some of the back and forths on this site, I've learned that you may not play very well with others.

So because your post adds nothing to the topic other than insults, I'm going to assume you were using my post as an opportunity to take a shot at someone else here and I just got hit with shrapnel. Because I know you wouldn't call me stupid.

[KE4AVB]

Something of note about primer side. It is normal for bubbles to appear when priming as some designs will allowing a little feedback air through the mixture needle paths. It is when there excessive amounts that you need may have a bad main nozzle check valve, bad metering diaphragm, leaky gasket or a combination of these. This something that will you learn as you gain experience with these carbs. Pressure and vacuum will only get you so far as you only test certain areas other you just got reason through and use modified testing methods such a section of clean fuel line that you can blow and suck on individual check valves and metering passages.

I had several Stihl Zama carburetors in the last few years that this has been a source lack of priming conditions even though primer section itself was fine.

The best diagnostic tools we have is our brain when used properly. As you probably already there are some that we deal with can make you wonder if it works at times. What I call running on Autopilot. Sorta like the guy that came by that couldn't start his mower after he removed the battery. Made my day.

[Fulltilt]

Something of note about primer side. It is normal for bubbles to appear when priming as some designs will allowing a little feedback air through the mixture needle paths. It is when there excessive amounts that you need may have a bad main nozzle check valve, bad metering diaphragm, leaky gasket or a combination of these. This something that will you learn as you gain experience with these carbs. Pressure and vacuum will only get you so far as you only test certain areas other you just got reason through and use modified testing methods such a section of clean fuel line that you can blow and suck on individual check valves and metering passages.

I had several Stihl Zama carburetors in the last few years that this has been a source lack of priming conditions even though primer section itself was fine.

The best diagnostic tools we have is our brain when used properly. As you probably already there are some that we deal with can make you wonder if it works at times. What I call running on Autopilot. Sorta like the guy that came by that couldn't start his mower after he removed the battery. Made my day.

Good point !
I suspect you meant to say clear fuel line, but either way, the ol' suck and blow method is the best ( and quickest ) way to determine the condition of the check valves.
I use a length of tygon that I cut squarely with a razor blade.

[KE4AVB]

I suspect you meant to say clear fuel line

Nope. I meant clean otherwords you don't want nasty stuff either going into the carburetor or in your month; unless, the taste of fuel mix or dirt is someone's cup of tea. Besides the air here is still clear so I can't see it moving. Now for how long it stays clear I don't know with the EPA dropping some of the clean air regs.

A little water in the line could be use an indicator but with experience you can get the feel if they are operating correctly so it is not necessary for the line to be clear, just clean.

[lefty]

So I ended up getting a kit for this carb since it's only 6 bucks and I figured I'm going to have a lot of spare parts from it for future endeavors.

My carb tools arrived too (thanks 38racing for the recommendation. They work great). So I pulled the low/high screws and because I want to give it a good cleaning. I figured I should remove the o-rings as well. So I grabbed my dental pick and gently pulled the first one out. Unfortunately, with my advancing age, I now need a pair of readers to see stuff up close. So when the o-ring popped off the pick and fell to the floor, I couldn't see where it bounced off to because of the glasses.

So I spent 2 hours today....Rick Moranis style, inspecting every inch of my shop floor looking for this tiny little O-ring. I regret to inform you all that I was unsuccessful.

Go ahead and give it to me Fulltilt. I deserve it this time...

For the life of me, I can't seem to find it online. It didn't' come in the kit and the parts lists I can find don't show it as a gettable part. Do I head to the hardware store to find a close match? I've made due in the past with generic o-rings. I managed to hold onto the other one so I have a good reference.

[NO0C]

Grab the calipers, size it up and head to a good hardware store.