Makita 6401 carb source

[howellhandmade]

I have an ex-HD rental 6401 that has been a great saw, except for idling issues. Always hard to keep it on the line between dying and the chain spinning at idle. Finally took a closer look and realized that the L screw appears to be stripped. If I push hard on the screw I can get it to catch and turn all the way in, but when I turn it out it loses those couple of threads and just spins, has no effect. Saw will run fine and sounds rich enough at full throttle but is slow to respond off idle, clearly too lean on L, using too much S to control idle speed.

I haven't pulled the carb out yet, but considering its age I'm thinking I'd better have a line on some parts, maybe a new carb before I get it apart. I signed on here for the first time in a long time looking for fordf150 and saw that he'd had a fire, search shows no posts since Oct. 2020. Dang.

I'd much rather order parts from a person than a website, both for the quality of information and to keep dollars turning where it will do some good. Recommendations?

 

[Oldsawnut]

A used husky 372xp

 

[Wood Doctor]

No guarantee, but you could try swapping the hi adjustment screw with the lo and see if that works. Like you, I hate it when parts suddenly are no longer available, especially for a good saw like this one. Mine starts and runs very well. Knock on wood.

 

[howellhandmade]

Thank you, Doctor. I can get a replacement carb, about $140, from Jack’s Small Engines, and I guess the saw has earned it. I reckon if anything would strip it would be the cast aluminum (?) carb body rather than the steel screw. An interesting solution would be to tap the hole larger and machine a new needle/screw, but I’d rather do that experiment on a spare carb. I guess I was hoping that there was a favorite AS Makita parts dealer.

OSN, that’s an interesting comment. A few years back I went through a bumpy patch and sold all of my saws but two. I sold my 660Magnum first; over the previous several years I’d actually needed it only once. I sold my 346XP because the 260Pro that I’ll keep if I have to sleep in the car with it was better handling (to me) and got used more. I sold my 361Pro because it was worth more than the Makita and, when I needed a bigger saw than the 260Pro, I almost always grabbed the Makita. I sold a nice Redmax 621 and kinda wish I hadn’t, didn’t get a lot for it and it had a great oiler. And I sold my 372XP. It was indeed a great saw and would have made a good saw for anything too big for the 260Pro, but it was really a pretty rare occasion when the Makita wasn’t enough while the Husky was if anything, a bit much. And the idea was to bring in cash. Besides that, I like inboard clutches.

I’ve been looking at new saws, and if I can’t get the Makita back on its feet it will probably be between the 372XP and the MS462. Used would be fine, too, but around here guys buy saws and sell Picassos.

 

[huskihl]

Thank you, Doctor. I can get a replacement carb, about $140, from Jack’s Small Engines, and I guess the saw has earned it. I reckon if anything would strip it would be the cast aluminum (?) carb body rather than the steel screw. An interesting solution would be to tap the hole larger and machine a new needle/screw, but I’d rather do that experiment on a spare carb. I guess I was hoping that there was a favorite AS Makita parts dealer.

OSN, that’s an interesting comment. A few years back I went through a bumpy patch and sold all of my saws but two. I sold my 660Magnum first; over the previous several years I’d actually needed it only once. I sold my 346XP because the 260Pro that I’ll keep if I have to sleep in the car with it was better handling (to me) and got used more. I sold my 361Pro because it was worth more than the Makita and, when I needed a bigger saw than the 260Pro, I almost always grabbed the Makita. I sold a nice Redmax 621 and kinda wish I hadn’t, didn’t get a lot for it and it had a great oiler. And I sold my 372XP. It was indeed a great saw and would have made a good saw for anything too big for the 260Pro, but it was really a pretty rare occasion when the Makita wasn’t enough while the Husky was if anything, a bit much. And the idea was to bring in cash. Besides that, I like inboard clutches.

I’ve been looking at new saws, and if I can’t get the Makita back on its feet it will probably be between the 372XP and the MS462. Used would be fine, too, but around here guys buy saws and sell Picassos.

I think he means a “used” carb from an older 372 will fit on your Makita. A Walbro hd6 or hd12, or Zama c3m from a 372 or 365 would work

 

[Wood Doctor]

If Huskihl is correct, this is indeed worth a gamble:
https://www.ebay.com/itm/2839417441...MI86unrfSy7wIVheHACh0m9AMfEAQYAyABEgIC-fD_BwE

 

[howellhandmade]

I think he means a “used” carb from an older 372 will fit on your Makita. A Walbro hd6 or hd12, or Zama c3m from a 372 or 365 would work

Ah. Thanks for that, I thought the linkages were different. My apologies, OSN.

Edit: confession time, all that for nothing, I pulled the carb, was able to reseat the L needle and retune from scratch, saw now starts, idles, zings right off idle. And it’s all clean! I’ll still hope to find someone who deals in Makita parts, because you never know.

 

[huskihl]

The 7900 uses a plastic choke handle with a metal rod. The 372 and 365 use a plastic choke with a larger plastic rod. The only issue using those carburetors on a 7900 is the size of the choke rod hole on the carb linkage. It’s a little bit sloppy on a 7900, but a piece of fuel line on the metal choke rod tightens it up and seems to keep it in place well enough

 

[howellhandmade]

The 7900 uses a plastic choke handle with a metal rod. The 372 and 365 use a plastic choke with a larger plastic rod. The only issue using those carburetors on a 7900 is the size of the choke rod hole on the carb linkage. It’s a little bit sloppy on a 7900, but a piece of fuel line on the metal choke rod tightens it up and seems to keep it in place well enough

Thanks, I’ll keep eyes peeled for one.

 

[kevin j]

Two or three years ago I bought a supposedly legit Zama c3m carb for my 7900 from a place called Mitty supply. I think it was Indiana Kentucky somewhere in there that part of the country decent price around $55 they said it was actually Zama Not a knock off, and that appeared to be correct. The company sells goat milking equipment and chainsaw carburetors. I have no idea how those two products got connected in the same company
You need to find an OEM mahle cylinder and piston take that thing up to 79 cc. You won’t have any more dreams of a 372

 

[Oldsawnut]

I think he means a “used” carb from an older 372 will fit on your Makita. A Walbro hd6 or hd12, or Zama c3m from a 372 or 365 would work

Yeah and way easier to source.. I do remember either flipping the choke plate or swapping it with the one from the dolmar... It was quite a while ago now and I don't have any more dolmar to swap out a 372 one with anymore