trimmer MCCULLOCH not running right any help/idea on this

angellonewolf

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to try to tell you all the story bought a trimmer non working would not start or run

guy said he replaced the fuel lines and diaphragm kit

i got the unit and all the filter in the carb was full of gunk so i removed all the bits carb cleaned and air line put back together unit started but would not throttle up

took the carb apart again and boiled the carb and air line blow through all is perfect and clean tryed starting again excect same problem if i put the unit on half choke it will mostly work fine throttles up ok

im thinking its starved of petrol or to much petrol

any ideas thanks for any help

ps will post a pic later
 

billsmowers

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THERE ARE 2 AJUSTMENT SCREWS ONE FOR THE HI SPEED ONE FOR THE LOW SPEED AJUST THE ONE NEAREST THE ENGINE 1/8 TURN OUT AND THE ONE NEAR THE AIR FILTER 1/4 TURN OUT TRY THIS AND SEE WHAT HAPPENS
 

angellonewolf

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Will have a look on this but can't remmember seeing adjustment screws I think it's one with no just meant

Forgot to say if choke on full the engine starts on runs I thought if unit is on full choke your supposed to pull untill it try's to start and then half choke to start ?
 

billsmowers

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OK POST A PICTURE OF THE CARB IT MAY BE ONE OF THE ROTARY CARBS IN WHICH CASE YOU WILL NEED A ULTRASONIC CLEANER TO CLEAN IT
 

angellonewolf

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Is there any point in trying to open up the by just bending the arm to try to let a bit more fuel in ?
 

billsmowers

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NO IT WILL FLOOD POST A PICTURE OF THE CAEB AND I CAN ADVISE YOU BETTER IF I CAN SEE THE CARB YOU ARE DEALING WITH OR POST THE MAKE & MODEL OF THE CARB
 

angellonewolf

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i think i may have cracked it from a thread i read a few months ago they said to cheak if there are any leaks on the carb and through to the engine by spraying some carb cleaner near it when this was done i heard a change in tempo so sprayed a fair amount and it runs ok and throttles up ok so i assume there must be a leak ?

i have taken apart the carb and extra plastic bit off the side of the engine but cant see any real holes or ways but now asking the question can i make my own gadgets for a temp measure to cheak if this is the right problem i do have make your own gadget paper but not the right gauge would this do just to cheak ?

thanks for the help i have added a few pic smoe of the pic are not that great
 

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Ifixdit

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i think i may have cracked it from a thread i read a few months ago they said to cheak if there are any leaks on the carb and through to the engine by spraying some carb cleaner near it when this was done i heard a change in tempo so sprayed a fair amount and it runs ok and throttles up ok so i assume there must be a leak ?

i have taken apart the carb and extra plastic bit off the side of the engine but cant see any real holes or ways but now asking the question can i make my own gadgets for a temp measure to cheak if this is the right problem i do have make your own gadget paper but not the right gauge would this do just to cheak ?

thanks for the help i have added a few pic smoe of the pic are not that great
It would be much wiser to buy the proper gaskets than to try and make your own. Their cheap and will save you a ton of headache. When you disassembled the carb did you also remove the needle and the pivot arm and the spring under it? If so, it needs to be reset properly or it just won't work. There is also a small round screen that can get clogged with debris very easily or can become completely clogged from varnicized gas and it won't run unless that is replaced. If you can't see through it, gas can't get through it. The screen is on the opposite side of the carb from the needle. Buy a walbro or zama complete rebuild kit with gaskets and the needle, spring, lever arm and new screen for around 10 bucks. Good luck and keep us posted how that works out.
 
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