MYSTERIOUS BOGGING DOWN

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Harold Bascom

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My Zenoah G290RC began bogging down badly every time I applied heavy throttle. Having read that when this happens it's an indication that the Low Speed Needle (LSN) is too rich and an overwhelming amount of fuel is being dumped into the combustion chamber, I began leaning it out by gradually by turning the needle clockwise in small increments. That didn't stop the bogging.

Another post prescribed leaning out the High Speed Needle (HSN). That didn't work either; the bogging down continued. It was a 'wits end' moment.

I Googled some more opinions and stumbled on something I never knew and hence the reason for this share, just in case there are others like me. Lol.

A response said that the problem was in the oil in foam of my air filter; that it was oversaturated, and that everytime I grabbed a handful of throttle, the oil from the air filter got sucked directly into the carb and caused the engine to bog down. (The truth was, the day before, I oiled the inner foam pad of my air filter and had a sneaking suspicion that I put too much filter oil on it.)

So, I took the oiled foam pad out, pressed it between wads of paper towel, and got the oil out. I then looked into the cavity of the air filter, there was an obvious amounta of oil in it. I swabbed it out. I put the filtering system back together, reset the needles to factory, and guess what?

The bogging stopped. PEACE!

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Proper oil filter maintenance is MANDATORY for healthy engine longevity. An excessively used dirty oil filter , or a filter that's not properly sealed will guarantee a blown crank. I'm running a custom 2 stage filter, and Maxima foam filter oil. I also like to smear a light coating of grease on the carb flange just to ensure no dirt can get past the filter.
 
Proper oil filter maintenance is MANDATORY for healthy engine longevity. An excessively used dirty oil filter , or a filter that's not properly sealed will guarantee a blown crank. I'm running a custom 2 stage filter, and Maxima foam filter oil. I also like to smear a light coating of grease on the carb flange just to ensure no dirt can get past the filter.
Thorough. I like that.??
 
Nice find @Harold Bascom. I came from nitro, so it was always common practice to use the sandwich bag method and press the excess out with paper towels after saturating. But there are a lot of newcomers for whom this is their first gasser of any kind and have never had to deal with this before, so this is definitely a great piece of info to pass along!

Cheers! (y)
 
Nice find @Harold Bascom. I came from nitro, so it was always common practice to use the sandwich bag method and press the excess out with paper towels after saturating. But there are a lot of newcomers for whom this is their first gasser of any kind and have never had to deal with this before, so this is definitely a great piece of info to pass along!

Cheers! (y)
I need to say this, I've ALWAYS used the sandwich bags to spread the oil completely through the foam element. The problem was I had too much oil saturated through it. It wasn't a case that after taking out of the sandwich bag the foam element was dripping. I KNEW it had more oil than usual but I told myself that all that would likely happen was something good: trap more dust. Lol. But I always say that everything, no matter how wrong, happens for a positive reason. With all my experience from nitro to my introduction to 2-stroke rc engines, I've learnt something new.
 
I KNEW it had more oil than usual but I told myself that all that would likely happen was something good: trap more dust.

Agreed on that sentiment 100%. I'd rather have my engine bog out because of too much oil than for any crap to get past it and totally wreck the cylinder!

Keep on rockin' that beast!
 
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