Was breaking in my engine earlier today. Think I did a pretty good job got it tuned pretty good. I was preheating it until the glow plug area temperature was about 220-230 but then I would check around halfway through the tank and it was only 140-170. I dont know why It did this. Could running it around the 150 side DRASTICALLY take away from the engine life? I mean if it takes away about a gallon MAX out of the life of the engine, I wouldnt mind as I will be replacing it with a new engine anyways later on 2013. So how can I fix this issue. I am running a medium-hot glow plug.

Are you still breaking it in?
If you are it's still probably really rich making the temps low...
I usually put foil over the head or a 1/10 tire form to keep temps up when breaking in.

No i finished the break in. DO you think next tank I put through it when I get it fully tuned, the temps will get up when I lean it out? Right now, it seems really blubbery so its rich.
As long as it goes up to normal temps when I tune it, i feel fine

so when you start it, the head is 230ish, but after it's been running the temps drop 70-80 degrees....it's also blubbery....your waaaaay rich.....and yes running an engine to rich can and will kill it sooner than having it properly tuned...the extra fuel/oil that gets pushed up into the combustion chamber don't compress, resulting in an increased compression ratio, causing more stress on the connecting rod, wrist pin, crank, piston, and glow plug

And again a new topic about your running in process.......

170 with the first tank running in is not that bad. Your engine will not set itself to the low temperatures the first tanks but you need to build up performance during running in to get to the operation temperature.

...and one tank is not nearly enough to call the break-in "finished"

I'm going to assume you're breaking in this engine outside.....if so, and your signature is correct (you're in Mass.), then you're going to need to wrap the head in foil, a 1/10 touring car foam tire, a small kid's sock, or something to keep the heat in.

If it's 40-ish degrees outside, you're going to lean the crap out of your engine to reach 230 degrees with a bare cooling head.....it's just too cold right now to get an engine up to that kind of temp. That's why tuning to a specific temp number is a bad idea, especially when it's cold outside.

Put something on the head of your motor, and understand that you'll likely be 20-30 degrees colder now, than if you broke it in during a 90 degree summer day.

And Josh is right....it'll be at least 10-15 tanks before the break in is done.

Ive done 5 tanks. 2 days ago. So today, do you think I should just do the break in again. Tank one today, quarter throttle, tank two today, quarter throttle for 3 seconds, tank three, half throttle, tank four half throttle for 3 seconds, tank five full throttle. Then after doing the break in process twice, do you think it will be broken in completely? Then I can tune it for performance then I should be good to go?

Plus, if i break it in to 180 or so, even if it screws the crap out of the engine and it will be junk once springtime comes; I ca treat this engine as my 'winter' engine because I'm buying another .15 engine for when this engine craps the bed. I think if It runs fairly good enough during these few cold months, Ill be happy. All i will have to do is possible replace the engine in the spring and do the break in when its warm out. And therefore that engine will last a while.

im not sure the others know you have a rtr engine. its probably close to broke in now but you got to get temps up without leaning it to much. try wrapping it with tinfoil plus your head wrap you bought to retain more heat and lean it a little but not to much see if that helps get temps up to 200-220 good luck but if not its probably to cold out

I have a heat gun that can get it up to around 240 degrees, then when I start it, with a sock over the cooling head, after doing a couple laps to warm it up, its down to 180. Do you think If i cover it with sufficient amount of tinfoil, then a sock over that, the temps will stay up so I can tune it?

Guys, I also havnt only done one tank and called it done. Ive run 6 tanks through it already with the break in instructions handy. Today later in the day when its close to 40 degrees out, I am going to run 2 more tanks through and call the break in process done. That would be 8 tanks through it. Again, if Im doing it all wrong, Im replacing the engine once it becomes springtime so Im not worrying too much about trashing it. When I ran it on the last tank (6th) 2 days ago, it seems to run less blubbery after I leaned it a couple of 1/8th turns. It just stalls because of the temps after idling for about 10-20 seconds. Do you think THAT is just the idle screw and I need to adjust it to idle faster?

all you can do is try it i dont like mine under 200 it needs that heat for piston and sleeve to seat properly

I started using the O'Donnell method for breaking in all of my engines, after I got on the team, and spoke to Steve O. It's 10-12 tanks, then left a little rich for the first couple of qualifiers (5 min each). After that, it's run it at race tune, and let it rip.....you've got 8 or so tanks on your RTR engine. It's fine to start leaning on it a little.

If you wrap the head during cooler months, you won't have to worry about hosing up your engine during break in because it will expand properly without leaning the mixture out too much. As far as running in colder weather, just wrap the lower half of the head with foil, and a foam tire. That will also allow the engine to heat up properly.

Don't try to tune to a specific temp though. Listen to the engine, and judge it's performance. Smoke, sound, and performance are the three things you need to tune an engine properly. Temp is a good reference point, or a gauge to make sure you're not way too hot, but that's all it is, a reference point.

If your engine is running strong, had good smoke, and sounds like it's clearing out well, and it's only at 220, don't lean it out to reach 250.

Also, plan on toasting a few of the RTR engines while you're learning how to tune. Traxxas has a good exchange program. Once you are decent at tuning, invest in a good motor.....it's a world of difference (much better).

Right now I think I actually got the hang of tuning. I got a perfect tune already and Im on my 9th tank of fuel. I do plan of replacing it sooner or later, but I dont feel comfortable spending big bucks on a 200 dollar engine, Rather Id just stick with the traxxas .15. Its fast enough for me and is really easy to maintain. I have had a great start and plan to learn more throughout my journey (that sounded weird)