How to Rebuild a Zama Carb for a Chainsaw

[@watkinwilliams1]

Many thanks for the video, I was just in the garage pulling my carb apart off my McCulloch and the needle valve assembly fell out, you saved me a lot of hassle, thanks

[@jonparkmac]

Cool. Glad it helped ya. Those tiny parts are almost too small for my sausage fingers 😂

[@FernsAndForest]

Excellent video; great instructions and filming. Thank you so much!

[@jonparkmac]

Glad it was helpful!. I always wonder if these reach people so glad to hear it's worthwhile ✌️👍

[@garymcmullin2292]

I never heard of a pulse feed to the oil tank for automatic oiling. You have to have an impulse signal to all diaphragm carburetors to be able to pump fuel into the carburetor. That impulse from the crankcase can be routed via an external hose crankcase to carburetor or it can be internally routed impulse through the cylinder/crankcase and directly into the carburetor body with no external hoses.

[@jonparkmac]

Now you have lol. The oil tank is indeed pressurized from a pass thru pulse on the carb .. that's why there is a 3rd nipple.. Many chainsaws use that system. You are correct about pulse and the fuel pump diaphragm. This is a branch off that pulse circuit. Check out my video on the HL Little Red and you'll see how it works. You can also read the Zama carb manual to get a better understanding of how they work. I too think this is peculiar ..but that's just how it works (and it does work)

[@michaelthompson839]

It was one part that you didn’t replace. You moved it at the 22:56 mark on the video. What is that part (little medal plate) called and how would you replace it?

[@jonparkmac]

Those are called welch plugs. When they drill these bodies they have to make turns and channels and the only way is to have openings. Then they press in those thin plates to cover it up. You CAN replace those and if the carb is dirty inside you should because there can be debris behind them that you need to clean out. If the carb is clean inside, I skip it. The ones I've opened are always clean. To remove them, drill a tiny hole and pick them out and clean the opening. Press the new ones in with the shank end of a drill bit. Sometimes you need to use an epoxy so it seals ..very small amount. Good question and thanks for pointing that out.

[@FASKY2788]

Thanks for bothering - really helped me!

[@ME-pw3kc]

what size screw is it for holding the carb pull lever on? mine fell out

[@jonparkmac]

Don't know ..you can go to hw store and thread check.

[@kyleree6757]

What's the little silver triangular pan for?

[@jonparkmac]

Those are new welch plugs and your supposed to take them out to clean the hidden area behind it and then press the new one in. I rarely do that ..only on a carb that is very dirty inside. But technically to be thorough..you should

[@kyleree6757]

@@jonparkmac Thanks

[@kajetancalczynski965]

@@jonparkmac Great video, unfortunately I watched it too late! I ended up trying to the the old welch plug out and scratching it in the process, before realizing that I dont have to change it. What is the correct procedure to get it out and press in the new one?

[@jonparkmac]

You can take drywall or other self tapping screw and carefully turn it into it till it touches the body underneath. Then you can work it sideways and it will come right out.

[@ddyeo503]

I have a Zama 2 and under the diaphragm there is a nylon piece with a round almost flat and also has a little pin on it to press on the needle and seat. On the diaphragm. This I have never seem before. The diaphragm is just flat with no center pin to press on the arm of the needle and seat,,,,,,,,,,,,,,,,,

[@jonparkmac]

All the 2 stroke carbs I've worked on have a disk on the underside and a small bump in the center that contacts the lever. Some are plastic and some are metal like this one. Common mistake is upside down and n/s never opens. Other mistake is gasket order wrong making it open too soon or two late

[@ddyeo503]

@@jonparkmac You know I couldn't find any videos on this older Zama carb. but I let the little pin like feature on the nylon piece not rest on the lever for the needle and seat and now it works fine. But putting the little pin on the lever where it is dented some, it will not work at all. That feature is very confusing ,,,,,,,,,,,

[@hmdwn]

How about a Zama "C1X" carb without any numbers/letters after C1X? It's off a very old Eager Beaver Leafblower.

[@jonparkmac]

@hmdwn I could not say for sure. I usually take apart the old carb and lay all gaskets out then compare to the photos on Amazon for the kit to make sure they all match

[@artgoat]

If you take the high and low adjusting screws out, the plastic retainer falls off with them. No need to rip it apart with pliers.

[@jonparkmac]

Well now ya tell me 😂. Good to know, makes sense thanks for the tip!

[@charlesoverton]

Do you use a Warburo vacuum gage.

[@jonparkmac]

No I don't use any vacuum gauges for 2strokes. I use pressure gauges for pop off and leakdown test tho

[@TheRancher03]

@20:41 just concentrate and don't let the spring fly off or you'll spend most of the time searching for it.

[@jonparkmac]

Ain't that the truth. Some people do it in a plastic bag lol. I've done this so many times and work on jet skis and gotten good at not loosing the little jimmies lol

[@_droid]

NASA needs to send up a craft to collect all our parts from orbit because I don't know where else they could be. 🤔

[@oldmanrock7542]

It's difficult to manipulate tiny parts with bear claws. My wife is very mechanical. I've been known to enlist her help.

[@jonparkmac]

So true .. these things are cheap to buy for the same price. I just like the journey and learning 🤘

[@timbrown2637]

I'd like the tech to show me where these imaginary check valves are.

[@jonparkmac]

Yes. I don't know what that's all about either. I don't see the need for any other ones beyond what's on the membrane.