2 stroke strimmer engine without air filter?

[visor_down]

Hi all,

I have just bought a second hand brushcutter/strimmer and having had a play about with it, I have found that when you remove the airbox cover there is no foam filter element?

Is this right? There are some fins moulded into the air box that would only stop the biggest of particles as in like chunks of wood!
Im sure it should have some sort of guaze or foam element, but there is no mention in the manual or on the net as far as i can see. Model is JCB-PBC25
/F

Cheers

 

[malcolm]

We've got a JCB strimmer - just as you describe without any filter element. Ours is completely rubbish - it doesn't start and cuts out when it gets hot. Only £25 new though so no great financial loss, but a waste of resources and space.

EDIT - looks like I have the cheaper model.

 

[Debs.]

Google would be your friend.

I`ve just done a quick Googley-search using the model number and there are quite a few results mentioning "a commercial grade air filter"......which may-well be a disposable paper element (rubber edged) type: missing from your filter housing.

 

[shenion]

I picked up a Homelite that was similar. There is a foam filter for it.

Malcolm, yours is probably running lean. There are adjustments on the carb for the mixture. Usually one farther from the engine is high-speed. Turn out until it starts 4-cycling (engine pitch sometimes cuts in half.) Then turn in a bit. Probably the idle is a bit lean too as hard starting. Running even a bit lean will overheat the engine.

Note: use synthetic oil. Cheap oil will run the bearings. I destroyed the bearings on a $300 R/C engine using Poulan oil. It turns to goo when cold and the balls slide in the races until they get warm enough to get loose from the cages.

Synthetic will also not foul the plug. Had a buddy that had to change the plug every year as it was dead each spring after sitting. Regular oil residue breaks down and becomes conductive. Had him switch to synthetic and no problems and no more smoke either.

 

[pointer2null]

I would have though there should be a foam type filter - they are usually soaked in oil (not saturated, just 'dampened'). Without it as mention the motor will run lean and also hot.

 

[a1fitter]

all engines use air filters to stop dust and grit geting into the cylinder it will score the piston and cylinder if a filter is not used the cost for a filter is penneys cyl/piston pluse labour ?????

 

[malcolm]

All engines should use air filters. Especially strimmers where you could kick up a fair bit of dust. But we're dealing with cost down experts here. My JCB strimmer was supplied without. Suspect the opening poster's one was too. They only have to last past the guarantee.

 

[visor_down]

Right as i suspected and as has been confired on here it should have a foam air filter. In case anyone Googles this in the future and comes across this post ....details are

Air Filter Sponge to fit JCB-PBC25
Available from Pulse Home Products 0161 6521211
Cost for this piece of foam £8!!! I avoided this and made my own in the end.

Thanks for the assistance, looks likely it has been run without the filter in the past, im guessing there is no way to say how much it will have shortened the engines life but can i check anything to see if it has been damaged? It starts first time and runs ok ATM.
Cheers

 

[Stuggi]

For any engine missing an air filter. Get some medium density foam (test it by blowing/sucking air trough it), soak it in synthetic 2-stroke oil, wring out the excess and install!

 

[bigwillyz]

go to a garden machinery dealer and ask if they got
any old pre-filters in the workshop honda,b&s,kawazaki etc
they all use them

if not new ones are very cheap just explain what you want
and if there any good they should help you out

when you got cut to shape and bobs your uncle

dont worry bout soaking it in oil we hardly ever do that anymore
nearly all machines now are dry only seems to be the old stuff

mike

 

[shenion]

Yes, dont just go grab any foam. The oil can dissolve many types of foam. I just grab any old foam filter and cut a slice the right size or get a prefilter.

 

[Stuggi]

Yeah, but if it's old you need to clean it, and nothing cleans filters better than petrol, and then you're going to need to re-oil it. The oil helps filter out most of the really fine crap, so it's quite desirable on any machine that's going to be running in dusty conditions.

Yeah, you have to make sure it's good foam, soaking it in petrol and seeing if it dissolves is one test that usually works.

If you decide on using an old filter, make sure it doesn't crumble as it isn't pretty when some synthetic plastic foam gets into your engine.