Received Asian MS440 Big Bore Triplets Today

[MustangMike]

The most frustrating ones are when there are multiple problems, 1st the carb, then the coil!

Nice when you get it all worked out! Currently have all 3 440 Big Bores Runing, plus my 046 D project. The Hemi jug 460 is also ready to go, they just sent me 440 tank holders instead of 460, and the moron on ebay does not seem to understand the problem.

 

[MG porting]

That happens sometimes a lot of guys think everything on the 440 and 460 are the same but nope not same. Lol. Some people I tell you.

 

[MustangMike]

Damn, this saw (#3) faked me out again! I changed the carb today, put an original HD-16 Japan carb on it. Sounds good, will see if the problem goes away.

Last time out she ran great for about 4 good size rounds, then started crapping out! If it is not the coil, and not the carb, I will try the fuel line and filter next.

Just hope it is not an intermittent air leak, but I'm leaning more toward a fuel problem. She idles just fine, it is when you pull the trigger that she falls on her face. If not the carb, perhaps a pinching fuel line???

Will be away this WE, doing the floor in my cabin.

 

[MG porting]

Damn, this saw (#3) faked my out again! I changed the carb today, put an original HD-16 Japan carb on it. Sounds good, will see if the problem goes away.

Last time out she ran great for about 4 good size rounds, then started crapping out! If it is not the coil, and not the carb, I will try the fuel line and filter next.

Just hope in it not an intermittent air leak, but I'm leaning more toward a fuel problem. She idles just fine, it is when you pull the trigger that she falls on her face. If not the carb, perhaps a pinching fuel line???

Will be away this WE, doing the floor in my cabin.

Are you using a oem vent?

 

[brshephard]

Might be a tank vent.
I had an 044 do what you described. The vent would pass just enough air to let it idle, but would run out of gas and go lean at WOT.
To check the vent run it till it dies and crack the fuel cap, if it's under vacuum you'll hear a woosh as it sucks air in.

 

[brshephard]

Are you using a oem vent?

You beat me to it lol

 

[MG porting]

You beat me to it lol

Lol. That's OK great mind think alike sometimes.

 

[MustangMike]

Nice thought guys, but I already checked that base, it is not the problem.

 

[MG porting]

Nice thought guys, but I already checked that base, it is not the problem.

hum very interesting you got good pals to the carb?

 

[MustangMike]

?

 

[brshephard]

I think he means impulse

 

[MG porting]

I think he means impulse

Yes Lol

 

[MustangMike]

Back from a WE upstate, ran saws briefly. #3 runs great with OEM carb, but sometimes choke does not come on. Worked when I first installed it, and looks the same (AM / OEM), but for some reason the AM chokes come on, OEM ones don't???

#2 started and ran great (has AM carb), but briefly gave me a "lean sound" also. I think I'm going to rip these AM carbs down and check the metering lever. I think they may be too low (I adjust #3 in the wrong direction the first time, these carbs look different than others I have seen, and was not sure where to adjust the lever).

Will keep you posted when I have time to do it.

 

[MustangMike]

Well, I have saws #2+3 running pretty strong, but will need to go back into #1 and give it some more intake.

So I go to run 2 + 3 today … 2 won't start (a first for it) even after 15 pulls, and I checked, the choke is on!!! and 3 starts, but runs like it has an air leak. Idles, but almost dies when you give it throttle.

I put OEM Walbro carbs on both of them and #2 popped on the second pull and ran fine, and #3 also ran just fine. The only problem I now have is the choke does not come on reliably. I have figured out how to fix this problem with a minor mod to the control lever, I just have to do it.

I think I'm going to buy some rebuild kits for my ZAMA C3M carbs and put them on the 440s, and keep the Walbros for my 046/460 projects. My 044 runs just great with the ZAMA.

 

[Terry Syd]

I think I'm going to buy some rebuild kits for my ZAMA C3M carbs and put them on the 440s,

You've got some Zama C3M carbs? You might want to send one to Poleman to mod and rebuild.

 

[Wonkydonkey]

what magic does poleman cast with his hands on these carbs.

 

[Terry Syd]

The 'twin jet' C3Ms can be modded for just about any engine. They have a superior idle/transition circuit to the Walbro and they can be made to pull like a tractor off the bottom (with the same top end). Poleman has a lot of experience for modding the carbs to different applications.

We used to be able to get the cheap Chinese 'twin jets' for less than $20. You could take one of those cheap carbs, with all new internals, and turn it into a great carb. Unfortunately, the Chinese replicas are no longer available.

MustangMike says he has several of the original Zama C3Ms. If he wants to, he can bump up the performance of his saws by modding those carbs - or sending them to Poleman to do his magic.

 

[MustangMike]

Good to know, thanks for the info. Funny how for years everyone posted that the Walbro was better, but I always liked how the ZAMA performed on my 044.

 

[huskyboy]

I liked the zama on my old 44, didn’t like it on 365/372 series saws. Walbro behaves better imho.

 

[MG porting]

I liked the zama on my old 44, didn’t like it on 365/372 series saws. Walbro behaves better imho.

Funny how that works out. Lol. Every saw has its own personality. Lol