Makita Strimmer Won't Start - Carburetor changed

[spunko 28,372]

I have a Makita petrol strimmer, it's only 3 years old or so.

It starts up fine, and idles over. But as soon as I start to exert any pressure on the trigger, even before it gets to 50% power, it immediately cuts out.

I consulted Google and apparently it could be the carburetor, so I followed this video to the tee, tried cleaning out the carburetor but it still has the same issue. Does anyone know what else it might be - I don't want to take it in to the local rip off repair bloke if I can help it.

 

Interesting fact I learned: Americans call strimmers 'weed whackers'. Twats.

[Gloommonger 2,011]

State the obvious, but have you put 2 stroke fuel in it and what was the mix ratio? 

Also, did you store it with fuel in the tank?

Edited March 7 by Gloommonger

[spunko 28,372]

4 minutes ago, Gloommonger said:

State the obvious, but have you put 2 stroke fuel in it and what was the mix ratio? 

Also, did you store it with fuel in the tank?

Yes I stored it with fuel in it, didn't realise you couldn't do that until I looked into it. Are you thinking it's the fuel line?

Can't remember the ratio but I am quite sure I got that right at the time. I haven't used it for at least 6 months.

[Gloommonger 2,011]

I always let petrol tools run dry before storing, stops the fuel drying to a varnish and blocking the carb or jet. Could be fuel filter, blocked jet, spark plug (unlikely). The fuel cap should have a vent, check it's clear. Does sound like fuel starvation. As you have cleaned the carb, it's probably a blocked jet. Don't know how easy it is to poke a wire down it.

[XswampyX 11,289]

What model is it?

Do you have two adjusting screws on it?

Try it without the exhaust.

[Long time lurking 24,595]

If you stored it with a full carb and it was ok before that take the carb off put it in a can /bucket of petrol with a lid on let it soak for a few days then refit it 

The chances are the jet(s )are blocked with varnish from the dried up/evaporated fuel  it`s sounds like it`s running on the idle jet only 

[Andersen 1,841]

Best drain any old petrol and refill with fresh (and 2 stroke oil if needed). Let it tickover for a few minutes to warm up before revving it - that might help.

Get an aerosol WD40 etc - get a can with a long spray nozzle. The carb will have a few adjusting screws, for every one gently turn the screw *in* and count the turns until it stops, remove the screw and use the wd40 to blow through the hole. Refit the screw, turn it all the way in, turn it out to the same original position (number of turns you counted). Repeat for all the other adjusting screws. The carb will have a few vent holes, use wd40 to blow each one clear.

Last chance - remove the sparkplug - clean it with wire brush - try to start with the plug out to clear the internals - heat the sparkplug (on you cooker) - quickly fit while still hot and try to start.

[Chewing Grass 25,693]

Guy round the corner has a mower business, inundated with work at the moment, my x,y,z petrol engined thing wont work.#

First question, did you remove all petrol before laying it up for the winter ( or even a month or so)?

Answer is usually no, I left the fuel in.

To which he replies, petrol from a garage has ethanol added to it, ethanol is hygroscopic so absorbs water (rapidly) from air.

This means water gets in your tank, if you are lucky you can drain the fuel off, remove any water and put fresh in.

If you are unlucky, the water (which has no ions in it as its from the air) is highly corrosive so will attack, copper, zinc & aluminium i.e. brass and die cast parts and so destroy the carb.

E10 petrol (10%) ethanol is coming in August, do not use it, buy the 4x more expensive alkylate petrol, Stihl or Aspen, this is pure 100% petroleum distillate, can be left in a machine for 5 years and won't destroy it.

Big advantage with pull starts is this stuff generally works first pull from cold.

https://www.mowersandspares.co.uk/products/aspen-2-alkylate-pre-mixed-2-stroke-petrol-1-litre/

Edited March 7 by Chewing Grass

[onlyme 12,475]

There's also fuel stabiliser that can help, not sure it will be enough with 10% ethanol mixes though. 

You can get a small bunch of carb jet cleaning wires for about £3 on Ebay which are useful for the carb  jet cleaning toolkit as well. You have a garden and tools, you'll be doing it again. 

[Caravan Monster 5,520]

I get quite a lot of 'could you have a look' (I'm not going to pay you) neglected small engine stuff to waste my time on. Noticed last year or so far fewer problems with water in petrol, maybe something got changed or added. Hope incoming E10 nonsense doesn't take us back to square one.

Re @spunko strimmer, as mentioned checking jets and flappy fuel pump plastic sheet in carb is a good place to start. A cheap compressor is a worthwhile investment if you have 'stuff', blower best thing for carb jets. I'm not familiar with Makita equipment, do they have the little plastic slide for hot / cold air temperature? 2 strokes are quite sensitive to air temperature because of how it alters the air / fuel mix. For the 5 minutes it takes, check there is a decent spark at the plug - rest (don't hold ) it against a metal part of the engine and pull the starter, should see a decent spark.

[onlyme 12,475]

12 minutes ago, Caravan Monster said:

I get quite a lot of 'could you have a look' (I'm not going to pay you) neglected small engine stuff to waste my time on. Noticed last year or so far fewer problems with water in petrol, maybe something got changed or added. Hope incoming E10 nonsense doesn't take us back to square one.

Re @spunko strimmer, as mentioned checking jets and flappy fuel pump plastic sheet in carb is a good place to start. A cheap compressor is a worthwhile investment if you have 'stuff', blower best thing for carb jets. I'm not familiar with Makita equipment, do they have the little plastic slide for hot / cold air temperature? 2 strokes are quite sensitive to air temperature because of how it alters the air / fuel mix. For the 5 minutes it takes, check there is a decent spark at the plug - rest (don't hold ) it against a metal part of the engine and pull the starter, should see a decent spark.

Had a stone saw that had a spark plug problem, would start up eventually and then die as the engine warmed u 0 presumably the plug  breaking down with heat - more than a few seconds though, more like half a minute or so.

[Bricks & Mortar 2,937]

I never used to have this problem, but its been the bane of my life these past couple years.  Reckon I've stripped and replaced a half dozen carburettors.  I don't think there used to be so much ethanol in the fuel.

The fuel stabiliser has done well for a whacker and a generator that don't come out very often.

I will only buy tools with Honda engines from this point, (assuming there's a choice).  I keep a couple spare carburettors and other spares on the shelf, and the spare parts are v.cheap if you buy knock-off chinese copies.

[onlyme 12,475]

1 hour ago, Bricks & Mortar said:

I never used to have this problem, but its been the bane of my life these past couple years.  Reckon I've stripped and replaced a half dozen carburettors.  I don't think there used to be so much ethanol in the fuel.

The fuel stabiliser has done well for a whacker and a generator that don't come out very often.

I will only buy tools with Honda engines from this point, (assuming there's a choice).  I keep a couple spare carburettors and other spares on the shelf, and the spare parts are v.cheap if you buy knock-off chinese copies.

Had a GX160 clone carb inc petcock and seals arrive this morning - just over £8 delivered, only actually needed it for the petcock washer as the cheap engine I picked up (unused but s/h) had a leak from the petcock valve assign as it was turned on, the was he on its own would have been half that. The chinese copy components certainly are cheap but a lot are nasty and maybe one of the reasons for additional maintenance issues, trick is knowing which to buy / scavenge off of genuine hondas and which to not bother with.