Be nice I'm part Canadian being my mom's from Victoria its a awesome place its very clean and there people are nice including Neil. people are different in there own way, where your from does play a big part its called culture.

Lol.. Joking...I love your bacon! Hate your fighters.

Damn, just changed bearing in my pratice engine - STS D21T - which is ABSOLUTELY not a high power engine The front bearing was full of dirt and so was the house like the photos from Neil on page one.
The bearings is only 6 liters old, but is extreme low costs bearing. After a few liters of fuel I could drag the crank in and out (just a little) but no side play. After 5 liters I started to ruin plugs after ½ a liter of fuel. Guess it was due to a big play in the bearings, so the crank pin and conrod thouched the backplate.
Don't know if thats the problem, but now I've blocked the vakuum hole and installed new bearings.
Read something about bearings. ABEC# is a standard for bearings. ABEC3 bearings is up to 32500 RPM (the once I just removed). ABEC5 bearings is up to 37000 RPM like e.g these bearings from ABEC35 14x25.4x6 steel

I realize this thread is a year old but i hope someone still follows it. Doing the soapy water test, my front bearing has a good leak in it but it doesn't leak oil or fuel which means it is probably sucking air in and this engine runs horribly inconsistent and the only way to keep it running is to turn the idle screw as far open as it goes. No this is not due to improper tuning as it will be fine and then all of the sudden start acting up which is what i mean by inconsistent. So what is this bypass port, where is it located, and how do i plug it up?

P.S. This was a brand new motor, nothing but problems straight from the box.

Make and model?

Some engines are just not well built

redcat aftershock 3.5. I spend more time trying to make it run than i do running it

You aint the only one thats had problems with trying to get a redcat nitro car to run

I highly recommend getting something worthy or contacting

yeah well the way i see it, after all that money spent on shipping, then redcat probably telling me its not covered under warranty and having to pay more shipping to get it back, i might as well overhaul the motor or buy a new one to slap in for roughly the same cost as the shipping. I want to get the Savage x 4.6. Anyway so how do i plug the bypass port, worth a shot

Most don't have that "bypass port". I would doubt that your engine does.

well how do i make the engine stop drawing in air through the front bearing? the OS 40 FP on my plane seeps oil through the front bearing and runs like a champ. My .25 POS on my redcat car does not. When the engine works right, it runs great but it can be seemingly perfectly tuned and then a tank or so later, won't run again

There are a lot of things that will cause those issues, not necessarily a front bearing. Bad fuel tank, fuel lines, carb leak, etc. To pin it down as the front bearing, isn't ideal.

If you want to be 100% sure it's not the front bearing, put a new one in.

i did the soapy water test on it, i sealed up the carb with rtv ultra black silicone and blowing through the fuel line while plugging the carb and exhaust with my finger reviled the front bearing leak. And this has been this way straight out of the box with little use because of these problems, i tried to break it in but i never got it to actually run without dying on any of the 5 break in tanks of fuel and i did everything your supposed to

Imbue is correct, it might not be the front bearing issue at all; if it ain't leaking nitro out from the front bearing after a tank of running, it's got nothing to do with that.

RC engine don't really 'seal' that well, if you put a fair amount of after-run oil or WD-40 in your engine and leave it there, sometimes you'll see the oil leak out from there, it's very normal.

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