break-in.

[andy_xr81]

i just finished breaking in the new 3.3 i got throught he ERP with traxxas. unfortuantley it got dark before i could tune it. willit be fine to tune from cold start next time, or would it be best to do a truncated break-in again? also how much play should there be in the pillow balls. when the truck is coasting along at low speed the wheels look like they are wobbling? ht ewheel nuts are tight so i'm thinking it might be the pillow balls. any one got any other ideas?

 

[jnjritz]

i just finished breaking in the new 3.3 i got throught he ERP with traxxas. unfortuantley it got dark before i could tune it. willit be fine to tune from cold start next time, or would it be best to do a truncated break-in again? also how much play should there be in the pillow balls. when the truck is coasting along at low speed the wheels look like they are wobbling? ht ewheel nuts are tight so i'm thinking it might be the pillow balls. any one got any other ideas?

I wouldn't tune cold. Start it up and drive her easy for a couple of mins. Until the temps get to about 200 to 220 then start to tune.
As for the wheels. Mine wobble also not really bad but I know its there. I don't see it when it's running but if I move the wheels by hand it does it. Don't know if this is normal but it has been this way for a long time and not bothering anything

 

[blckrevo33]

my wheels are the same way as jnjritz says,the only thing you can try is tightening the carriers a little it might help. i did on mine and it helped but they still wobble a little by hand.

 

[bobbyc1127]

try tightening up the pillow ball retainers. those tend to either back out or just not be tight. one good point to remember on tuning. get the motor warmed up and tune from half a tank. remembering that as the fuel level gets lower in the tank the motor will lean out as it is sucking more air in from the tank. and don't tune by temp. it will only drive you nuts. tune by preformance. snappy bottom end punch good smoke trail, and also when you punch the motor you want to see a nice puff of smoke trailing off into a light constant trail of smoke. tuning by temps will only make you want to pull your hair out. one day the motor will scream at 220 the next it will at 250, alot will depend on the air and humidity that day.

 

[jnjritz]

I don't think i can totally agree with you on this one bobbyc. I would like someone to correct me if i am wrong. But no matter if the tank is topped off or half of tank the pressure is going to be pretty much in the same ball park. give or take a couple of .02 Of a Psi << Example!!
Not really in my eyes enough to lean her out to a unsafe point. Or to a unsafe tuning point. I tune mine when it gets up to temp, Ie... 200 to 220. And it runs the same temp from full tank to almost empty. (Of course when it is running out of fuel and has air bubbles in it from running out It will be lean.) But if the fuel line is full of fuel, the pressure will stay the same.

As for not tuning by temp. I feel it is a great idea to keep an eye on the temps while tuning . While you can not get a perfect tune by temp tuning, you can get an idea where it wants to run for the day with what ever weather it is out. And it helps so that you don't smoke a perfectly good engine. You use it as a guide line.

This is IMO.... If i am way off please someone tell me. I just do not want anyone missinformed.

 

[frickenjoey]

Well Bobby and jnjritz you are both correct....partially. I tune an engine once it is warmed up. It is pointless to do it while it is cold. However no need to do it a half a tank or lower. If you are tuned good the tank level does not matter quite as much so that is not a huge factor. Ok, tuning for temp AND performance. What I do is generally tune it to where I think it is running well on low end and top. But while I am doing this I am also checking my temps to make sure they are safe. Then once it is where I think it needs to be I am going to make several hi-speed runs and heat it up a bit and check temps again. All the time making sure it is not in the danger zone. I like keeping below 270! Even though out the bash session I will check the temp from time to time....just because. Better safe than sorry. Oh yeah pillow balls can be a PITA...check 'em out...just don't over tighten them.

 

[jnjritz]

Thanks Joey. Just making sure i wasn't giving bad info
You said it better than i did That is basiclly what i ment. I do both afte I get the performance out of it then I tune by temp. Lowering it if need be. I like to keep it around 240 to 250 just to keep it a little on the rich side for bashing.

 

[bobbyc1127]

i was not saying it was rules set in stone gentlemen. i should have phrased it differently..this is the procedure i use and i am sorry if anyone took it the wrong way. i do temp my engines occasionally making sure i am not cooking them. i race my revo and seldom ever bash it. for a good racing tune i take my motor up to around 250 to 260. yes i know it is high but like i said i race my motor and want full preformance. about 80% of tht time during racing my temps will stay between 240 to 255 at the end of a heat or main. but i always return my motor to bottom dead center to try to get the sleeve to return to it's taper as close as possible.

 

[jnjritz]

i was not saying it was rules set in stone gentlemen. i should have phrased it differently..this is the procedure i use and i am sorry if anyone took it the wrong way. i do temp my engines occasionally making sure i am not cooking them. i race my revo and seldom ever bash it. for a good racing tune i take my motor up to around 250 to 260. yes i know it is high but like i said i race my motor and want full preformance. about 80% of tht time during racing my temps will stay between 240 to 255 at the end of a heat or main. but i always return my motor to bottom dead center to try to get the sleeve to return to it's taper as close as possible.

Oh no no.
I was not being confrontational. I was putting in my 1/2 a cent. Even for bashing 240 to 260 is ok. It's when you get up more than that I stay away from
It was mostly the half a tank thing i was questioning.

 

[liftedcj7on44s]

Tank level DOES make a big difference in tuning. I can tune my revo and have temps around the 265-270 mark. As soon as i get below half a tank the temps will climb upwards of 290-300.

The motor will run leaner the lower the fuel level is in the tank.

 

[jnjritz]

See now in all of my riggs i never had this happen to me. Just when it was about to shut off. I never have seen a big increase at all. Huh.
I guess you learn something new everyday.

 

[bobbyc1127]

See now in all of my riggs i never had this happen to me. Just when it was about to shut off. I never have seen a big increase at all. Huh.
I guess you learn something new everyday.

the reason i say half a tank...the tank is pressurised.(never said i could spell) as the fuel level lowers the more air is pumped into the tank keeping it primed. although it is pushing the fuel into the line with the level droping air starts getting into the fuel line causeing a leaning condition. this is the reason i tune at a half tank. i have ran my truck out of fuel after a night of racing and i temped the motor at an empty tank and it was hitting 285ish. at an empty tank i don't think it was hurt. but remember these are what i call throw away motors...i mean $115 with a trade in....yeah not a big expence.

 

[kommando98]

My wheel wobbles too

My front left wheel has been wobbling like crazy since I got it out of the box...at high speeds it isnt as noticeable, but at low speeds it looks pretty bad. At one point during break-in the front left wheel and tire came completely off when I was turning it around...even though I had made sure that all the wheel nuts were properly tightened...luckily enough I was able to find the wheel nut after only walking around for about 5 minutes, it would have been bad news if i didnt. Just finished the break-in today, and have already gone through a spark plug...I'm using an MC8, and it seems okay. Thats an okay one to use, right?

On the plus side, I love the Revo 3.3 engine already...my last traxxas engine was the Pro .15 in the first version of the Tmaxx...this is a big step up.

 

[bobbyc1127]

the 3.3 likes a hot plug. like an o'donnell red or something equal to that.

 

[liftedcj7on44s]

I run the traxxas 3230 hot plugs in mine. And for the wheel nuts take and make a couple cuts in the backside of the nuts and that will make them bite into the wheel and they should not back off anymore.

 

[kommando98]

wheel nuts and glow plugs

thanks...I put some thread lock on them before putting the wheel nut back on and that seemed to hold better...I'll try the cuts on the backside of the nuts as well...

I forget where on the table the MC8 glow plugs fit in...are they considered in the "hot" category? It seemed pretty close to the same size and fired up first time with the mc8 in there, so i figured it was okay...