Makita EK6100 disc cutter self revving while idling. can someone clarify what the issue?

[Jonny Vee]

I got this disc cutter off Ebay in a box completely apart I have to say that I have never seen this disc cutter running. I found out piston ring was missing and took me a month to get one in stock. Assembled the saw. Started at first pull but I'm having hard time to tune it. And while left idling sometimes it self revving.

I got the impression a crankcase seal may be leaking. But would like to hear some of you.

I wouldn't not think about carburetor issue but happy to hear from you.

Thanks

 

[Burnerman]

Self revving is usually due to a weak mixture at the low end of the engine RPM range....power may suffer too as the engine accelerates.
This may be due to an incorrectly adjusted carburettor (there could be two screws on the side of the carb marked L and H - it's the L one to adjust here.
Firstly though, does altering the tickover screw (often marked LA) make any difference?
Crankcase oil seals on a two stroke are vital in their condition......as the crankcase is under negative pressure then air can be drawn in as the piston rises. However, you may see oily deposits in that area, behind the flywheel for example.
Grab the flywheel and see if you can move it up and down.....seals usually fail with the roller bearing behind failing too.
Personally I'd try to hunt down some carb diaphragms and gaskets for this one - stone saws get one hell of a hard life! Do be scrupulous regarding air filter condition too....often there are three of them.
John

 

[Jonny Vee]

Self revving is usually due to a weak mixture at the low end of the engine RPM range....power may suffer too as the engine accelerates.
This may be due to an incorrectly adjusted carburettor (there could be two screws on the side of the carb marked L and H - it's the L one to adjust here.
Firstly though, does altering the tickover screw (often marked LA) make any difference?
Crankcase oil seals on a two stroke are vital in their condition......as the crankcase is under negative pressure then air can be drawn in as the piston rises. However, you may see oily deposits in that area, behind the flywheel for example.
Grab the flywheel and see if you can move it up and down.....seals usually fail with the roller bearing behind failing too.
Personally I'd try to hunt down some carb diaphragms and gaskets for this one - stone saws get one hell of a hard life! Do be scrupulous regarding air filter condition too....often there are three of them.
John

Thanks John

I tried to set the L screw as seems like Makita does not allow you to set up the H. Can't see much through the hole but there a screw but can't be moved with a screwdriver like for the L ones. Nothing has changed still behaving odd.

Parts for those saw are a nightmare and expensive but will investigate and see if can get carburetor kit.

Will update

 

[Burnerman]

Genuine carbs are around the £60 mark, but diaphragm kits are available......there will be some sort of ID on the carb body itself which you will need.
There should be three adjusting screws; L for low speed (11/2 turns out from fully in); H for high speed 21/2 turns) and a larger one beneath those two which mechanically touch an arm coming out from the carb.
My usual recommendation of GHS Ltd may come up trumps here.
Good luck with it!
John