can a nitro engine run too cool??

say i dont no after 4 consecutive drift tanks with my 4-tech i could pick it up by the cooling head right after i shut it off

is this too rich??

can i hurt my motor running too cool??

please help

Yes it can hurt to run too cool. You need to check temps to make sure you are up to running temps. If you can pick it up by the head and it not burn then yes its too cool. Lean it out and either do a water drop test or use a temp gun. If it runs too cool you risk breaking a connecting rod. Should be between 220 and 260 for best performance.

(i broke it in last december)

ok so i should lean it out

i ran it very rich to drift and figured it couldnt hurt, i will get a temp gun and use that now.

nothing broke(engine wise), and it still runs like new could i have done internal damage? like piston and sleve wise?

You will get alot of crap from guys saying a temp gun is not needed. Once tuned no its not needed but when you run too cool or too hot its good to have for insurance. Tune for teh best performance then check your temps. If you are tool cool then you know you can go leaner. If its running hot then richen it up. Once you are in the ball park you can just turn the high speed needle a tad either way when the weather changes.

true that

thanx

once i know the engine is broke in,i tune by smoke trail/performance,but always keep a temp gauge close at hand just in case,i have had engines develop an airleak,lean out and hit 400+degrees

yeah the i still like to have a temp gun handy just to see if it is running at good temps but if you drift i would really consider a temp gun b/c your engine will get really hot

meh, in my opinion temp guns are useless, i've never used one, never had to, if i want to find out if it's over heating i just touch the cooling head, after a while you learn whats to hot, whats to cool and whats right from that, the only time i can see a temp gun being more useful then learning to tune without one is during break in if your doing an advanced heat cycle.

yea thats the thing i was drifting 4 consecutive tanks and i could pick it up by the cooling head!!! it was just really warm

Here is an article that I pulled explaining what could happen when running a engine too cool.

What causes the connecting rod on my ABC engine to wear when it's run very rich for long periods? Most would think that extra oil in the fuel would help, not cause harm. The worst thing you can do to an ABC-type engine-other than running it lean-is to run it rich for long periods. When new, most ABC (aluminumalloy piston with chrome-plated brass cylinder) engines exhibit an interference fit (components that actually touch) as the piston crown passes top dead center (TDC) when turned over by hand. In many cases, you can actually hear the piston squeak; this is normal. Originally designed for fast, 2-cycle operation, the piston and cylinder expand similarly (slightly more for the cylinder), maintaining a good gas seal without enduring the mechanical drag of a piston ring. Unfortunately, when operated at a rich 4-cycle (engine firing once every other revolution), the piston and cylinder never reach design temperature and the piston rubs at TDC, causing great wearing loads (pounding) on the piston wristpin bosses and both connecting-rod holes. The piston fit also is worn away at its crown, further degrading the engine's mechanical condition. In the future, always try to run ABC-type engines (including the AAC and ABN types) in the 2-cycling mode, especially when they're new.

Yep i agree,i've never had a temp. gauge as for example i can hear when the tank is running empty(it's about the ear,i've tuned 1:1 cars with twin-twin choke carbs by ear and pipe)however for some a temp gauge is reassurance.Overall it's whatever works for you.

good to know

thanx

i guess i will be leaning it out a tad

And here is an article I wrote showing what happened when I deliberately ran a new ABC "too cool" for 45 minutes.
http://www.rcuniverse.com/forum/m_28..._1/key_/tm.htm

Briefly, for those who don't want to read it, after 45 minutes in a full 4 stroke and a head temp down to 145F the piston was as new, the chrome on the liner was beginning to polish, the pinch didn't change and the rod was running in very nicely with no detectable wear.

This was not an attempt to run in the engine, this was an experiment to find out if the myth was true.

the chrome was beginnig to polish bad or no?

cause mine was only running for about 30 minuets

my opinion on temp guage- good to have on hand but not nessesary

I think a lot of it might depend on how tight the engine is in the first place...and the quality of materials used in it's manufacture.

If you have an engine that is a typical "sport" type engine that's designed for bashing it's probably got less of a pinch than a higher quality race engine, and will withstand some "abuse". (they are designed with the knowlege that there will be some people with little or no previous experience operating them )

I wouldn't want to run a new and squeaky tight (read: Novarossi, or RB, or engines of that sort )engine excessively rich for very long...just about as long as it took me to tweak the needles and lean it some...

I've run ringed airplane engines so rich that they needed the glow plug battery connected to stay running (even @ WOT ) but that's another story, aye!?

To try and answer the O.P.'s question though...it can prematurely wear the piston, but at the temps you are talking about I don't think you need to worry much.

Just one example...don't know how relavent it is here but...
I had a Thunder Tiger ,46 Pro (airplane engine ) that I flew year round, and that includes 15 degree winter days, snow storms, rain, etc.
It didn't like to be throttled back for long when it was really cold out, because even w/ a hot plug and more nitro, it would quit if given throttle on a "go around", until I wrapped alum. tape around the cyl.
I measured cyl. head temps as low as 110-115 degrees...and that was @ WOT leaned out.
I flew the snot out of that engine...put about 10 gallons of fuel through it before it started loosing power. (that was because it sucked in some dirt and the Nickle started peeling, but it still had a little bit of a pinch left at TDC believe it on not![8D])

What is optimum temperature in celsius?
I have a temp gauge, which wraps around the head, and then shows the current temperature as well as peak hold
How accurate are these? And are they a good idea to have? My motor has reached 160 deg C on hot days. I assume thats too much

WHOA 160c is 320 fahrenheit. Thats way too hot. You need to be around 120c to be optimum. As for the onboard temp gauges yes and no about being accurate. It all depends on where you place the lead wire hoing around the head. Some have to be as close to the bottom of the head to read good and others have to go up further. What I do is place the wire on the head and get the engine hot. I will use a temp gun to see actual temperature. If the temperature on the onboard reads high you move the wire up 1-2 fins up. You just move the wire around until it gets close to the temp gun. Once you do this you wont need the gun anymore.

if u have a on board temp gauge throw it in the bin

I ran the wire inbetween the head and block
No temp gun though to test anything

I have a Losi 8ight t and it ran awesome with about 1 gallon of fuel in it.The temp was about 230.f I have other cars and they were alot hotter so i started running fans and cooling heads.The next run after i installed a cooling head on the losi it started blowing glo plugs every race...the temp now at 160f.Then after 3 runs the engine made a snapping noise and quit sudden and was siezed tight.Upon tear down the piston was siezed with a broken rod, bent liner etc....i suspect the temp too cool and piston/liner too tight and making metal and eventual locked engine....so run them above 220....hope this helps.

on boards suck your not getting a reading from the location you want it from which is right in the center of the head at the glow plug. Getting a reading on the outside of the head or block does not work hense the reason feeling the head to test the tamp is kinda foolish. Yes putting your hand on the head at the races helps you get a idea where your temp is at and will help you once you know what it feels like when it is at the temp that it should be anyway. Temp guns are not going to break the bank but a new motor can. Yes I know people who don't like to tune by temps but more by oil stream and performance but you NEED to keep a eye on your temp or your going flat out plane and simple burn your motor up. I personaly spend big time $$$ for my mills and I will never hit the track without my temp gun.


Running a 4 stroke motor cool is in no way the same as running a 2 stroke motor so I'm not getting the 45 minute run thing.

WOW someone alse that thinks like I do! Totally agree 100%