TRX 3.3 engine problems

[kevinF]

that little blue beice fell in there when i was looking......I blew it off

[kevinF]

I think it sucked in some dirt through the exhaust system.....cause there are scratches on the bottom of the connecting rod and a small gouge in the piston......i always hade the air filter on there....the only way it could have gotten dirt in is becuase of the o.s. header, cause before i bought a some rubber things for the o.s. header to fit it wasnt making a seal.....so dirt must have gotten through there becuase i couldnt even shut the engine off with my finger on the exhaust, it would just keep running......

so im guessing that dirt got through the exhaust port then scrathced the bottom of the connecting rod and then it eventually made a litlle gouge on the piston.......not big enough for it to blow the engine but just enough for it to blow glow plugs and idle funny

[Czech-it-Out Graphics]

sorry bud, but thats impossible lol

[Ponch]

I really doubt that it came thru the exhaust. It looks like you have alot of scrap on top of your piston.

[Czech-it-Out Graphics]

Judging by the piston, there is a slight bit of detonation or pitting on the edges, prolly from the low deck height. The bead blasted look on top is from running lean. If i get a chance I will show you what the top one of my pistons loooks like

[kevinF]

ok....well im sending it into traxxas so hopefully theyll fix it......but it was only at 290 for a few seconds and still had plenty of smoke coming out

[Czech-it-Out Graphics]

you may have been lean bottom rich top, or rich bottom lean top, and not have even know it. I am betting it was the second case.

[Tex]

That piston shows signs of running lean, I disassembled my 3.3 the other day and had a dark brown maple syrup color going.

[kevinF]

ok.......well its weird cause becuase i went to hte track on tuesday I had a brown maple syrup like color ring and the rest was good.....i must have run too lean at the track and thats why it was blowing glow plugs.......how do i know if im too lean then?

[Traxxas_Junkee]

well it wasn't cutting out, and the temps were good so.....

[kevinF]

you know what....my temp gun was prolly off, becuase remember when it was sizzling kyle??

my temp gun was prolly off.

it wont start cutting out till it hits about 320-330

[Czech-it-Out Graphics]

thatll do it, did u go to LH? those long ass straights. Did u re tune when u got there, i would recommend opening ur HSN about 4-5 hours before even hitting the track

[Ponch]

Also, check and make sure your airfilter ain't dirty.

[kevinF]

well the motor is shipped off to traxxas........they will hopefully figure out whats wrong with it.......oh and I just checked my temp gun, it works good now.

maybe it got screwed up when i dropped it 20 feet onto rocks cause travis didnt catch it.

I dont think my temps are what are causing me to blow glow plugs, its something else.

[Ponch]

maybe it got screwed up when i dropped it 20 feet onto rocks cause travis didnt catch it.
.

What?!!!!?? Were you up on the driver's stand or something?!??!?!

[Tex]

The long strait isn't any different than running through a field or in the street out in front of your house.

If it was sizzling it was over 320F, probably around 400F. Also motors don't have to be at a certain temp before they start cutting out. They cut out because of lack of gas, not being to hot. If your too lean your engine could cut out even when you first start it, while the motor is still cold.

The "cutting out" is due to no fuel in the crank case, IE, too lean.

I know you said it wasn't cutting out and you saw smoke but it was definitely too lean bro, motor might be shot.....

[kevinF]

dang.......well how do i tell if its not too lean then??

matt yeah i was on top of the drivers stand and threw it down to travis and he missed it.

maybe that impact screwed it up enuogh for a few seconds and caused it to be too lean and the temps got to high and fried it

[Czech-it-Out Graphics]

well when ur goin down the straight does it whine out quickly and then seem to slow down almost on its own toward the end of the straight, almost like it is dieing out? like Tex said no fuel man u scorched that puppy

[Czech-it-Out Graphics]

u cant depend on temps sometimes, if its not running to its optimum performance than u need to re tune. sound is important, and also experience. You should be able to "feel" a difference in the motor when it is and is not tuned right

[kevinF]

well i have never had this problem with any of my other engines.....it was going kinda slow down the straight cause of no traction so i leaned it uot a bit and it was a little faster.......I must have leaned it out too much and didnt hear it cause travis and kyle were driving with me

[rocco79]

Hella clear pic dude! nice...

Sadly it does show some signs that there may be some big problems...

Was there and compression left in the engine or was it gettin loose??? How bout when it was warm? would it roll over easily then?

[Czech-it-Out Graphics]

rocco all motors roll over easy when they are warm...lol

[Tex]

I think he means REALLY EASY. not just easy.......

[kevinF]

nope it had plenty of compression. I dont understand hoe it could have been to lean.....I had soooooo much smoke comin out and the temps were mostly at 230-250

well i know i went down the back straight and my slipper clutch was super loose to weere i hadi t full throttle and it was barely moving.....could that explain the lean and why it had a rough top??

[Traxxas_Junkee]

that could have done it too, with the loose traction, the motor was revving higher, could have heated it up faster, and then when the slipper kept coming lose the same thing happened, hopefully traxxas will give you a new p/s