Revo must die

[saddlehorse]

Got the revo out, had it tuned great yesterday and today it runs great at low throttle but anything over that and it cuts out like loosing fuel ,so I richen it up still same thing ,lean it out still same thing. If I let off throttle it will idle if I stay on it ,it dies
Guessing air leak, any ideas and thanks

 

[REVO-5309]

changed glow plug? how old is it? could of lost compression and need new piston/sleeve?

 

[saddlehorse]

New glow plug with maybe a tank on it. Revo has maybe a gallon and a qt in it.

 

[MudSlinger33]

Try sealing it up. Otherwise ditch the 3.3.

 

[ozziii]

Just ditch the 3.3.

Fixed,hahah

 

[saddlehorse]

Been thinkin about goin to big block. Never been happy with power of 3.3
tear it down next day or so and if it needs rebuild, then bb will take its place

 

[saddlehorse]

Pulled glow plug and coil is all bent up. Too much compression?
Why just start that?

 

[2revo1maxx]

It's usually from running lean. Make sure your exhaust is tight too.

 

[JoeMAXX]

If you suspect an air leak the first thing is replace the fuel lines or cut the ends off each end by 1/4 of an inch. This will reseal the fuel lines unless it has been melted in the middle from hitting the engine or exhaust.
Air leaks in the fuel lines show bubbles while watching the fuel flow thru the lines. Carbs can leak if they come loose and this is a fairy easy one try and twist the carb on the engine. If it twists a little tighten the set screw. If you really want to prevent any leaks on the carb use a sealeant. I like to use the Copper Colored RTV Sealent over the Black RTV Sealent because it has a higher Temp resistance.

The Glow plug will blow out from running too lean. Richen the fuel mixture more. Engines will mostly cut out from running too lean because the get really hot. I would suggest investing in a temp gauge while you can use it for tuning it will also tell you when the engine gets to hot.

The Traxxas 3.3 engine is an awesome engine that will take temps up to about 260 to 290 degrees before they cut out. Nominal running temps are about between 180 to 220 degrees on this engine. Like most engines once they get above 260 it is too hot and they do not have enough oil in them to reduce friction hence too lean of a mixture.

 

[saddlehorse]

Ordering an onboard temp gauge soon. Guess till then I will tear it down to clean and seal it up.
Thanks

 

[JoeMAXX]

Ordering an onboard temp gauge soon. Guess till then I will tear it down to clean and seal it up.
Thanks

Do not buy the onboard temp guage and invest in a hand held one. If you ever own more then one nitro R/C you will need it more often.

 

[saddlehorse]

What is a good hand held unit?

 

[JoeMAXX]

You can pick one up these days for about 25 bucks

I bought mine years ago from radio shack not sure the sell them anymore.

http://www.harborfreight.com/infrared-thermometer-93984.html

http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXEMG5&P=ML

 

[2revo1maxx]

A good engine will cut out because it's too lean, not because of temps alone. If a well tuned engine is over-worked it will run well into the 300° range, but still be rich enough to stay running. It's also not wise to tell people what a good temp range is for any engine. The 3.3 works well between 200° and 260°, but it depends on fuel choice, ambient conditions, and tuning.
Tune for performance.

 

[saddlehorse]

Tore it down to clean and seal. Found rust between head and block and between backplate and block.
Clean it all off and sealed it up. Also noticed carb isn't closing all way when you let off throttle but will if you move it by hand, also not opening all way everytime . Seems like it is straining to open it.
What can I do to fix the carb to open, close better???


Well atleast now I know the Guy lied about using after oil, rust proves him on that.

 

[chickenman242]

I had I similar problem with the 3.3 in my revo, apart from the fact the previous owner had no idea what he was doing
The carb would jam open or closed and would stick in places and not open fully, I readjusted the carby around clockwise until I got full movement and sprayed a bit of wd40 down the throat until it was sweet
If that is still no good mayb3 look at a losi 3.4 carb bout 30 bucks on ebay and its meant to be way better to tune, I was going to do that but my 3.3 had no compression so I couldnt tune and ended up scrapping it

 

[saddlehorse]

Was wandering who made the 3.4 carb I kept hearing about.
when you hit throttle on radio the linkage rod will bow out where it is trying to open carb alway but so I will try to lube it.
Thanks

 

[Nitro4910]

Losi makes it, it comes off the Losi 3.4(comes in the Ten T), & one of the eBay cop shop's is your cheapest place to get one.
http://www.ebay.com/itm/Losi-Carbur...racter_Radio_Control_Toys&hash=item2a2754a909

 

[saddlehorse]

I hear it makes a difference on performance also, is that right?

 

[chickenman242]

From what I've heard and supposedly make the 3.3 easier to tune also