MCCULLOCH The official McCulloch thread

[Maintenance Chief]

Im from europe so no shipping will be worth it... thanks anyways!

Ive ordered a rebuild kit, still isn't delivered, but it doesnt appear like they have a check valve included.

Meanwhile, i dont know how i didnt figure this out earlier, but i had spare transparent/meshy type membrane lying around, and the old check valve was from the same material...so i cut out a small piece that fits, put back that brass thingy and 3D printed welch plug (PETG), works like a charm! Cant feel any leakage at all while sucking through.

I did realize that the check valve kit would be difficult to get in the UK.

 

[Steve]

Im from europe so no shipping will be worth it... thanks anyways!

Ive ordered a rebuild kit, still isn't delivered, but it doesnt appear like they have a check valve included.

Meanwhile, i dont know how i didnt figure this out earlier, but i had spare transparent/meshy type membrane lying around, and the old check valve was from the same material...so i cut out a small piece that fits, put back that brass thingy and 3D printed welch plug (PETG), works like a charm! Cant feel any leakage at all while sucking through.

The check valve is made of the same material as the metering diaphragm. I have made one using a hole punch and a spare diaphragm.

 

[Al Smith]

I don't know about shipping to Europe would be but shipping to Australia Via US airmail for a small package like a carb rebuild kit would be about 5 dollars US funds .From Ohio to Australia takes about 4 days .
Some time back I had sent a CD with pictures for a 1938 Bridgeport milling machine to a web sight called "lathes UK" in England .It too was around the same price .Machine tools are another of my very many interests .
In addition I get generic prescriptions from an online pharmacy in British Columbia in Canada .They are shipped from India but go through Sweden .Slightly larger packages 10 dollars US shipping cost .

 

[Steve]

I don't know about shipping to Europe would be but shipping to Australia Via US airmail for a small package like a carb rebuild kit would be about 5 dollars US funds .From Ohio to Australia takes about 4 days .
Some time back I had sent a CD with pictures for a 1938 Bridgeport milling machine to a web sight called "lathes UK" in England .It too was around the same price .Machine tools are another of my very many interests .
In addition I get generic prescriptions from an online pharmacy in British Columbia in Canada .They are shipped from India but go through Sweden .Slightly larger packages 10 dollars US shipping cost .

I didnt think it was too bad either Al

 

[popopboat]

Okay, good and bad news.
Good news are that check valve still works flawlessly, bad news are that some new problems have occurred.
Saw starts right up, idles perfectly, accelerates perfectly (better than seen on the video, i have readjusted the carb afterwards)
Works flawlessly in the cut, four-strokes while lifted, doesnt when cutting, and it is really consistent, no changes in the rpms at all... and then the problem comes, after releasing the throttle after longer cut, sometimes idle starts running, sometimes just cuts off, then T screw has to be screwed to the right few turns, after starting again to the left for the same amount.
Carb is sitting there tightly, no temperature related air leak (because when started again it goes to absolutely normal idle while still being hot).

Any ideas?
Im thinking about tank vacuum, but not entirely sure because i think i have opened a tank and nothing changed.

Can anyone tell how should metering valve lever be adjusted? (ive set it a milimeter bellow carb "body")
How many turns by default (ive set it to around 1.5 turns out on L and 2 out on H)

 

[Steve]

Okay, good and bad news.
Good news are that check valve still works flawlessly, bad news are that some new problems have occurred.
Saw starts right up, idles perfectly, accelerates perfectly (better than seen on the video, i have readjusted the carb afterwards)
Works flawlessly in the cut, four-strokes while lifted, doesnt when cutting, and it is really consistent, no changes in the rpms at all... and then the problem comes, after releasing the throttle after longer cut, sometimes idle starts running, sometimes just cuts off, then T screw has to be screwed to the right few turns, after starting again to the left for the same amount.
Carb is sitting there tightly, no temperature related air leak (because when started again it goes to absolutely normal idle while still being hot).

Any ideas?
Im thinking about tank vacuum, but not entirely sure because i think i have opened a tank and nothing changed.

Can anyone tell how should metering valve lever be adjusted? (ive set it a milimeter bellow carb "body")
How many turns by default (ive set it to around 1.5 turns out on L and 2 out on H)

Metering lever should be flush with the two embossments on the floor of the metering chamber. Make sure the diaphragm is latched into the fork of the metering lever.

 

[Maintenance Chief]

Okay, good and bad news.
Good news are that check valve still works flawlessly, bad news are that some new problems have occurred.
Saw starts right up, idles perfectly, accelerates perfectly (better than seen on the video, i have readjusted the carb afterwards)
Works flawlessly in the cut, four-strokes while lifted, doesnt when cutting, and it is really consistent, no changes in the rpms at all... and then the problem comes, after releasing the throttle after longer cut, sometimes idle starts running, sometimes just cuts off, then T screw has to be screwed to the right few turns, after starting again to the left for the same amount.
Carb is sitting there tightly, no temperature related air leak (because when started again it goes to absolutely normal idle while still being hot).

Any ideas?
Im thinking about tank vacuum, but not entirely sure because i think i have opened a tank and nothing changed.

Can anyone tell how should metering valve lever be adjusted? (ive set it a milimeter bellow carb "body")
How many turns by default (ive set it to around 1.5 turns out on L and 2 out on H)

It should be set level with the carb body , not below.
The factory settings should be 1 full turn out from lightly seated.
Your needle settings might be high due to the fact that you have the metering lever set too low.
Check/ replace the cap duck bill valve if you have not yet.

 

[popopboat]

Ok, kit has arrived.
Replaced metering diaphragm, membrane, complete metering valve stuff.
Check valve still works flawlessly.

BUT IT SIMPLY WONT RUN, or pretty much start at all
I adjusted everything as it was before when it was running and starting beautifully (both screws and metering diaphragm), but now i have to pull and pull, sometimes it chonks a bit then dies, wont idle no matter what i do with L screw, when it starts running a bit i have to always pull a throttle so it doesnt die... What now?

I checked every passage, nothing is blocked, or anything else...
No holes in membrane or diaphragm, impuls line is working.

 

[Steve]

Ok, kit has arrived.
Replaced metering diaphragm, membrane, complete metering valve stuff.
Check valve still works flawlessly.

BUT IT SIMPLY WONT RUN, or pretty much start at all
I adjusted everything as it was before when it was running and starting beautifully (both screws and metering diaphragm), but now i have to pull and pull, sometimes it chonks a bit then dies, wont idle no matter what i do with L screw, when it starts running a bit i have to always pull a throttle so it doesnt die... What now?

I checked every passage, nothing is blocked, or anything else...
No holes in membrane or diaphragm, impuls line is working.

Pressure/vac test. Change the sparkplug. Could be fuel fouled. Also check spark. Should jump 1/4"

 

[popopboat]

Unfortunately cannot really do air leak test but, it can very easily be bogged town with excess fuel so i suppose no air leak present here.
And it blows through exhuast too good for any signiticant leakage.
I replaced sparkplug with working one (definitely), and i can light a room with the spark lol.
Im running out of nerves and ideas... Never had such an issue, everyhing else started working one way or another, but this one... just wont.
Metering valve is opening properly, leaks fuel through main jet when i press diaphragm with little screwdriver.

And yes, i tried with throttle wide open, wide close, LH both to the right... with choke... nothing.

 

[Steve]

I does not take much of an air leak to cause a problem. What is the compression?

 

[PogoInTheWoods]

Establishing the integrity of the crankcase is an absolute must before you do much else except maybe drain the crankcase out the plug hole (or exhaust) of what is probably a lot of accumulated fuel. At this point I'd guess it's terribly flooded and will take some time and effort to get it dried out. Hell, a perfect carb won't start a flooded saw. Just because it's flooded doesn't mean the case and intake are tight.

And ditto on checking your compression. Multiple factors could be involved in creating the current situation. Air leak(s), low compression, timing, carb still not right, or all of these. Eliminate (or identify) all the possibilities one at a time. You'll eventually find the problem(s).

 

[popopboat]

Well, perhaps it could be terribly flooded, even tho if tried deflooding it multiple times.
Dont know, im 99% its carb related :/, will check spark timing tommorrow.
Well, in the matter of compression, i usually dont use decomp valves, but on this one i have to.

 

[heimannm]

Mark

 

[popopboat]

View attachment 258205

Hmm, do i like yellow because these are yellow, or i like these because they are yellow...

Well i finnaly got it running atleast somewhat properly, wants to jump from acceleration, left it to idle while i stacked the firewood (cca 5 mins) didnt hear any significant rpm changes.
Doesnt die after cutting... Rpm sometimes slightly changes, but not enough to be near dying or spinning the chain. And all i did is repeated same stuff i already did 10 times.
However L screw seems to be overly sensitive, so i suppose something is a bit wrong with needle or the seat, cant do much yet.

But the thing is one hell of a drinker...

 

[Maintenance Chief]

Often multiple problems follow each other, fixed the carb and bad lines show them selves, carb ,lines and spark all fixed? Air leaks become more apparent.
First things first before you chase your tail , see if it has an air leak , get a can of non-cholranated(spell))?) brake cleaner, start the saw with out the clutch cover off and spray some at the seal ,(obviously dont have the bar and chain on the saw) , if it kills the idling saw BAD SEAL! its a little more difficult to get the starter side but the leak wil suck in the brake clean and shut the saw down.
Running it with a bad seal will eventually roach it.

 

[popopboat]

Nevermind, ignore everything prior to this. Found the problem... but dont know how to feel about it...

Im pretty sure that L needle hole shouldnt look like this... Dont know how i missed it all this time.
Someone was really sensitive while adjusting it.


Atleast im relieved by knowing that i didnt mess up anything... Just checked pictures i took more than a month ago, while assembling it first time, and it was like that all this time.
I guess ill have to live with it, atleast i can adjust it good enough so it idles somewhat properly.

 

[Al Smith]

As long as it isn't running lean you can deal with it .Eventually you will find a better one to use . Looks like somebody ham fisted that thing .It's a little screw not a cylinder head bolt on a big diesel .

 

[fossil]

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Mark

Great to see you finally got one Mark!

 

[Gizzard]

Not so common a 10 series recoil cover there Mark. Thanks for posting the pictures.