Burnt plugs

[Brushlessboy]

Hi guys. My Revo has me a bit stumped. I have just had a bit of a play and after 5 minutes or so she stopped. Dead glow plug.
I stuck a newbie in it and 3 minutes later, dead plug. TOO LEAN I thought. But that didnt seem right, at idle she is still spittin a bit of oil, and the hsn is pretty much still at factory settings. So I leaned the hsn out a little, then a little more, till she bogged at wot. I richened it up a bit but 3 or 4 minutes later, another dead plug.
Please, any suggestions.:surrender

 

[Rolex]

It sounds like you have covered the carb settings, so the next thing is a run of bad plugs, or just the wrong type. Post which engine you're running and the plug type and number, and one of the Revo pros will help out.

 

[frickenjoey]

Ok richen it back up......run it for a bit. Spitting a little before it is up to operational temp is kinda normal. Put it back to where it was spitting a tiny bit when it first starts up. Keep it there for say, 1/4 - 1/2 tank, check the temp. You should be tuning your engine using the best performance with your temps in the safe range. Also what kind of plug and fuel are you using? I know a lot of other folks will chime in here soon so keep your eyes open.

Damn Rolex beat me to the first post...... Morning Rolex! Actually evening for me though...lol

 

[Rolex]

Good Evenin' frickenjoey. Get a good nights sleep. You have KP tomorrow.

 

[Brushlessboy]

Thanks guys. Its the 3.3. I'm running 25% Nitro and LC3 plugs. Running it for 1/2 tank is hard frickenjoey cause it doesn't run that long, although I haven't tried it at idle. The plugs did come from the same run, (I tend to buy them by the card) but jeez loiuse, talk about tough.

 

[frickenjoey]

No kidding.....that is tough luck I have plugs with a gallon on them and still work. If you are running rick and still burning them out.....I don't know what to say. What temps are you getting to? Is the filament actually breaking? Does it look like the piston is hitting the plug? Look at the top of your piston and see if there are any marks or abnormalities....

 

[jetmechG550]

What do they look like? Are they wet and oily or shiney and the coil looks almost whitish and distorted?

 

[martrix]

If you can't keep it running after 1/2 a tank, you may have already overheated it ! = Irreversible damage to the pinch in the piston and sleeve.

When engine is cold, can you turn the flywheel past TDC with your pinky finger?

 

[Brushlessboy]

The motor runs ok and sounds good, its not pinching, but the plug looked like a lean burn. No broken filament, just dark and dry. Motor is was set a little rich, and the weather was a little cooler than when I last tuned it. Might have leaned out cause of temp or humidity???? I have richened it up a little more and it ran for a tank, good temps. But is set richer than it should be, even for the weather. Should I start looking for it sucking air somewhere?

 

[martrix]

When engine is cold, can you turn the flywheel past TDC with your pinky finger?

I had a second hand engine that ran great for the first half of a tank, then it would always stall at idle. Pulled the piston and sleeve and sure enough, I could push the piston all the way to the top of the sleeve = 1 useless piston and sleeve.

When they warm up the sleeve expands and starts to straighten out the taper, thereby reducing the pinch. If yours is low on pinch (or pop) when it is cold, it will be much less when its up to running temps.

Here is a quote of what I'm trying to get at. It is still very possible your engine is not stuffed, could be just a tuning issue.

One thing I find is that people confuse compression with pinch. New engines do have alot of compression, but they also have alot of pinch. When engines are fairly easy to turn over by hand people tend to say they are shot, which in most cases is not the truth. I just got a tm and it doesn't have much pinch, but I still get a good pop out of it, I'll prob send it out to get pinched just so I can use it for the whole summer, but if I had got it with a month left to go in the season I wouldn't have it pinched I would still run it. I haven't had a chance to really put it through its paces, but I ran it for about half a tank and it has a strong idle and insane power.

I guess what I'm trying to say is this....if you find your engine is running great and isn't flaming out then your all set. When you find that your in the middle of your tank and the engine flames out and takes a long time to restart, and it happens often chances are your mill is on its last legs.