McCulloch spark plug

[ipbr21054]

Hi,
Just purchased the following.
McCulloch Euroma H60 hedge trimmer.

Im looking to purchase a new spark plug preferably NGK
Anybody have a prt number.

Ive contacted McCulloch & NGK & both a waste of time.
I cant go by the plug fitted as its finger tight & not sure if its the correct item

Thanks

 

[Burnerman]

Give me a pic of the thing and I’ll have a go.....if its short but with a large hexagon then BPMR7A won’t be far off.
John

 

[conny]

If it's only finger tight that may be the problem. Take it out, check it's clean, should be a light brown colour. If blackened or oily wipe with a dry cloth and gently brush with a light wire brush. Check the gap is correct, (should be 0.6-0.7mm). Re-fit and tighten by hand. Once finger tight use a plug spanner to tighten fully but do not over tighten. There should be a compression washer fitted to the plug. If this is missing buy a new plug and check gap before fitting.

 

[ipbr21054]

Hi,
Plug now ordered thanks.

I purchased this item cheap to do two small jobs it was also a non runner which is ok as i think i can get it going but so far i have failed.

First i must ask,the on / off switch is missing so they have connected the two wires through a fuse.
When you start these petrol items you put the switch to on & start it up then off to kill the engine.

My question is what is on when using this fuse Connected or Disconnected ?

So not knowing if the fuse is to be connected or disconnected for the on position i have done the following variations.
Fuse connected & then fuse disconnected.
Choke off, then on & then half way.
Throttle lever applied & also left alone.

None of the above worked so i have then done the below but still does not start.

I have used a known working spark plug.
Checked that a spark is present at the spark plug & yes there is.
I have taken the carb off & also apart & then cleaned it using carb cleaner.
I have also removed the fuel tank & drained off the oil fuel,cleaned it out & replaced with fresh fuel/oil.
I have removed the fuel lines & fuel filter & cleaned them out.
I also squirted some carb cleaner in the plug hole.

I then screwed both H & L screws in then out 1 1/4 turns.
When i pull the start cord the blades do move against each other.

Any advice what to do next or did i miss something

As yet i have not touched the exhaust side

 

[ipbr21054]

Here are some photos attached.
As you can see the fuse is connected so would this be the same as the switch in the ON or OFF position ?

I have removed foam air filter and also exhaust.
Still no joy.

 

[ipbr21054]

With the air filter and carb off should i then operate the lever the operates the flap inside the carb should I see a squirt of fuel as I don’t.

Primer bulb seems to stay full of fuel.
If I pump it I also don’t see a squirt of fuel.

 

[ipbr21054]

Here is the full primer bulb.

Also asking if fuel pipes are on the correct way around.

Top hose green has fuel filter on it.

Bottom hose white is just placed in the fuel tank.

 

[Burnerman]

Who knows why a fuse has been used here.....it certainly isnt necessary but I would imagine you would only get a spark with the fuse removed - do check it!
A full primer bulb is a good sign but isnt an indication that fuel is being drawn into the engine, unfortunately.
Does the spark plug ever seem to be wet with fuel?
Just to ascertain the engine isnt flooded, take the plug out, turn the machine so the plug hole is downwards and pull the engine over. Any spray of fuel here shows flooding.
John

 

[ipbr21054]

Hi,
I will check that tomorrow.
Before I finished for the night and my right arm is three inches longer than the left with all the pulling it nearly started.
With the fuse removed then the wire isn't grounded so I left it off.
I removed the plug, it seemed a little wet but not much.
I held a lighter flame to it for a while and tried once again. It was at this point it nearly started.
The first / second pull I would start a white mist came out of the exhaust I say mist as I don't think it was smoke.
Two three times then nothing.
So with the original plug I did the same with the lighter.
Put it back in and same as above.
I thought it was going to start as it was the best result that I had.

Does this sound like no spark or little spark as I burn off the dampness with the lighter and I thenhave a ray of hope. Maybe not sparking enough or at all just makes it damp full stop.
Earlier I said there was a spark and I stand by that as I had seen the spark.

 

[Burnerman]

With these engines, pushing the primer button does not give a squirt of fuel at the carb jet.....it simply fills up the chambers of the carb, ready for the fuel to be sucked into the engine.
Vent the engine as I said in post #8 then:
Give the engine full choke and full throttle, pull the starter briskly until the engine fires once then;
Full throttle, no choke, pull again and the thing should start.
Heating the plug up is an old trick, and for sure worth a try!
John

 

[ipbr21054]

Ok
Should I be checking for coil resistance also with multimeter?

Just asking now so I can gets a head start with time / replies this morning.

Thanks.

 

[Burnerman]

No need...just look for a spark with the machine in the dark or shade. The spark sould be blue in colour.
I presume, the machine has good compression - you can feel the compression as you pull the engine over?
John
P.s. I see numerous machines like this where the owner just doesnt have the correct starting technique - so its well worth mastering.
J.

 

[Nozzle]

I have removed foam air filter and also exhaust.

Put them back on again, the exhaust at least. 2 strokes run like a bag of spanners if you go messing with the gas flow, as taking off an exhaust would do

Nozzle

 

[ipbr21054]

I only removed them one at a time so i could see if there was any difference of which there wasnt.
I didnt remove them & leave them off

 

[ipbr21054]

Here we go with an update.


The fuse was only used i assume as a kill switch as the on / off kill switch is missing.
Not sure why he used a fuse as he could of just touched the wire to the engine.

Sometimes after trying to start it i remove the plug and it is damp.

As per post #8 i removed the plug & turned it on its side & pulled it over,didnt see anything come out so i tried again using some tiisue but still dry.

Plug removed & finger over plug hole then pulling the cord i can feel the compression wanting to push my finget away.

So now i have turned both screw in then out 1/2 a turn.
I have put tape on the throttle handle to keep it open.
I have then tried to start it with the choke on, then 1/2 then off.

After a few pulls of each i then turn out both screws 1/2 a turn each again & try again with the choke operations.

After i got to 2 1/2 turns & choke off it started & run for say 3 seconds then died.
Tried straight after but nothing.

So now i have stopped & started to write this for you to await your thoughts on this or what to do next