dunno about the X2 too much best bet would be ask on the buggy forum http://www.rcuniverse.com/forum/forumid_244/tt.htm

My son has a new MT2 and we are having steering issues. Basically, the steering gets very tight and at times the front wheels get stuck and won't move at all. I don't think it is the servo (although I can't say for sure) because when I disconnect the ballcup the servo seems to rotate fine. It almost feels like a piece of gravel or something is getting stuck and preventing the wheel from returning to straight but I can never find anything in there. When we do get the wheels "unstuck" it still doesn't turn as sharp and quickly as it should. We've had the wheels get stuck three times so far and each time I don't really even know how we got it working again - it just seemed to kind of start working on it's own (but with limited steering). I will probably tear the steering system apart tonight to see if I can find the culprit but if anyone can give me some ideas to look at I would appreciate it.

Also, the brakes are not working that well either. I put in a longer piece of fuel tubing and adjusted the brakes to fully engage but they just don't have the stopping power and the car half coasts to a stop. I belive the car has the fiber brake pad. I am thinking that maybe some fuel/oil got on the brake pad but I don't know if that woud cause this ungoing problem or not. Many of you may have seen this issue posted on my previous thread but I thought I would post again here in case there are people not watching that thread. Sorry about the redundancy.

I am going to be placing an order soon for spare parts for the car so if there is anything I need to replace for either of the above issues I hope to get them in that same order.

Thanks,

Matt

edit: I also forgot to ask, what is the typical running time for the car with a properly tuned G3 engine. His run times seem to be fairly short compared to my RC10GT and we also seem to be spewing a large amount of nitro. I am guessing we are too rich and that is keeping our runtimes short but I am nervous about leaning it out too much. I am going to order a heat sensor to better tune the engine but in the meantime I thought I would see how his runtimes compare to the norm to get in the ballpark.

Run times will vary with driving style and the engine tune. If you are spewing fuel you have it set too rich. Turn it an hour at a time (as if the needle were a clock dial) until you have it set where its running strong, there is a nice trail of smoke on acceleration and the temps are good.
As for the steering, check the servo saver. It could be too lose or too tight. Also Ive had rocks get caught under the steering plate under the front end so take a look there.
The stock brake/throttle servo is not that strong. If you have replaced the fuel tube and the brake pad is good then you may want to go with a servo with more torque.
Good luck and keep us posted what you find

Thanks for the reply. I just got in from tearing everything except the drivertrain and shocks apart. Nothing seemed too out of the ordinary but I did notice a few things.

First, when I had the fuel tank out I took a piece of fuel tubing and plugged it into one of the holes on the tank. While plugging the other hole with my finger I blew into the fuel line. I noticed that air came pretty easily out of the tank through the lid. If I pressed down on the lid fairly hard it would almost stop the flow but I could hear just a little bit escaping still. If I wasn't pressing on the lid there wasn't much resistance and the air would come out pretty freely. Is this the sign of a leaky tank or is it normal? I couldn't find anywhere else I would be leaking and a leaky fuel tank coincides with the location that the fuel was concentrated in the chasis. It could be that we are just running it too rich, but there is quite a bit of fuel collecting on the car - too much it seems to be only coming from the pipe. Plus the performance seems to be pretty decent and the engine warms up nicely so I don't think I could be that overly rich. I may just order another fuel tank since they aren't too expensive - unless someone can tell me that it is definatley not the fuel tank.

Second, as far as the steering goes, I think it is at least partly a weak (and maybe damaged) servo. It just seems slow, weak and inconsistent. However, I also think my son may have messed with the D-R(?) trim knob on the transmitter because it was set at less than 1/2 way. When I turned it all the way to the right I got a bit more travel, although it was still not great. I think I may just upgrade to a BB high-torque servo and be done with it.

Finally, I am a bit baffled by the brakes. To get them so they will really grab I have to have them tuned so that there will be a bit of brakes at idle. However, the manual says that you want it to roll free at idle. They just don't seem to grab that well if I have it set to roll at idle though. Is it ok to have the brakes slightly applied at idle? Maybe a new throttle/braking servo is in the cards as well.

Other than these issues, which I am sure will get worked out, the car is awesome. Makes me almost want to sell my RC10GT and get one of these instead. Still, there is much to be said about the simplicity and reliability of the GT. Maybe I'll just keep the GT and get another MT2 for myself...

Matt

Is the fuel coming from the exhaust pipe when the truck is running or are you finding fuel somewhere else on the chassis? Burnt fuel residue will be sticky because it will be the left over oil that passed through the engine. If its leaking prior to the engine it will be wet.
The dual rate setting will definitely effect the steering. Turn it all the way up and see if that helps. Also disregard what I said about the servo saver,was thinking of another car when I wrote that. Check under the front for rocks though, they do get stuck in there sometimes.
If the brakes are dragging at idle its no big deal. As long as they release when you get on the throttle you are fine. The brake set up on the MT2 isnt that great. Fortunately its a fairly light truck so it stops pretty well. A better servo will definitely help though. Also you may want to change the servo horn set up for the throttle to get some better response from it. Ive attached a picture of my set up

Thanks for the reply and pictures Keith. I am definately finding wet fuel on/in the chasis and I am pretty sure it is coming out of the fuel tank. I am going to order a new tank as well as a couple new servos which will hopefully take care of the steering and braking issues - or at least help significantly. I'll look into changing the servo horn set up once I get the new servos in there.

Thanks again,

Matt

Did you check all the fuel lines for pin holes? The tank cover doesnt need to seal that tight because it has very little pressure in it, though the o-ring could have dried out. You might be able to change the ring rather then replace the whole tank. If you can, take some pictures of where you're finding the fuel.
Better servos will definitely help a LOT.

I've replaced the fuel lines and still had the problem so they should be ok and it's a brand new car so I don't think the o-ring could be dried out. I didn't have to blow into the tank hard at all to get the air to come out. I couldn't feel where it was coming out but I could defiantely hear it. It could be the seam where the tank was put together but I'm just not sure. I think I'll just order a new tank, they're only $11 or so. If nothing else, it will eliminate the tank as being the issue.

As far as servos, what would you recommend? I don't want to spend any more than I have to but I want him to have good steering and good throttle and brake control. Would the Futaba S3010 do the trick? They're pretty cheap and seem to have decent torque. How about the S3305? I think that is very similar to the 3010 except for metal gears, right? I am putting a fairly large order together and I will include the servos in it.

Thanks for all of the help.

Matt

It could be a bad seam on the tank then.
As far as the servos go I prefer JR or Hitec. Futaba makes good servos but Ive had better luck with the other two. The JR Z650m would work well for both the steering and the throttle servo. Its costs a little more then the Futaba you were looking at but its a better servo. And definitely go with metal gears. It will save you in the long run.

Thanks for the reply Keith. I took your advice and looked at Hitec and JR servos. I think I'll go with the Hitec HS-645MG. It has metal gears and dual ball bearings and is close to the same price as the Futabas. The JR Z650m appears to be discontinued.

Matt

Anytime. Glad to help.
Keep us posted on your progress

The Hitec 645MGs a good servo got 3 of em and happy with the performance
There is a guy on ebay that is always selling them for around $28 shipped that I got mine off of, I got them in 2-3 business days off him.

I just ordered three from Tower (went with next day shipping so I can get my son off my back). I am actually going to put two of them into my RC10GT and then take my Tower Hobbies High Torque servo that is in it right now plus the third Hitech servo and put them in his truck. I ordered a bunch of other stuff for his truck too (tires, springs, etc...) plus a couple of Lipo batteries for his RC18T so he should be pretty well set and happy for a while.

Thanks again for the help.

Matt

Just a quick update on my issues. I received my order today and installed the new fuel tank and servos. The issue with the fuel leaking onto the chasis was absolutely a faulty fuel tank. The new tank provided a more air tight seal and after running a couple of tanks through the truck there was not a drop of fuel or oil on the chasis. Problem solved. Also, the Hitec servos made a big difference in the steering department. My only issue was the screws that the servos came with didn't have long enough threads and fell out on the third tank. I'll have to go to the hobby shop tommorow and get longer screws. I would use the screws that came with the truck but they aren't machined and the new servos take machined screws. Finally, I was able to get the brakes working much better. I adjusted the servo location at neutral and that combined with the more powerful servo did the trick. I am just trying to finish up tuning the engine and of course getting the new servo screws and it should be good to go. Thanks again for all of the help.

Matt

good to hear its running right now.

Are you talking about the screws to connect the servo horn?
If you need machine screws try True Value hardware if you have one nearby. They carry a pretty good selection of metric screws. And they are pretty strong as well.
Glad to hear you've got it running better.

Or Ace hardware.
Last time I needed some weird ass sized screw for a RC thay had it dirt cheap

Thanks for the heads up on the screws. I checked Ace and they didn't have them. I ended up getting some from the local hobby shop. Now that I got those on I am having issues with starting it once again. Funny how it will run through several tanks one day and then the next day you can't even get the engine to fire up. Oh well, I'll just rebuild and retune.

Matt

If its the same glow plug you used for break in than it may need to be replaced. Sometimes metal shavings collect on the filament

hey guys i just bought a used mt2 off ebay, looks to be in good shape! i was wondering what are some of the more usual items to break on these trucks and what should i go ahead and assume im going to need to replace with strong alloy parts? im not looking to hop up this truck that much for now, but i wanna know what to expect breakage wise from normal wear and tear, thanks guys! im excited

hey i have a nitro xcellerator i recently crashed in to a wall and broke the right front control arm and i replaced it and now when i turn the wheel to the left it makes a clicking sound what is causing it please

fishy it depends on how you drive the truck. For the most part its pretty durable but the screws strip out of the plastic knuckles occasionally and the diffs on the original MT2 are pretty weak so you need to watch those.

Josh is it making the noise when the truck is rolling or just when you turn the wheels to the left. If you crashed hard enough to break the A arm you probably bent the drive shaft / dog bone.

Hey guys, quick question. ( i know that this the mt2 thread, but this is a more generic nitro question). i just bought an hpi nitro monster king. i was trying to do the break-in, so i added fuel, got it started, it was reving REALLY high.. so i hit the brake..i tried messing with the trim (it's the same radio as the stock mt2 one) and tried messing with the idle screw, i ended up just riding the brake so it didnt rev so high.

my main question is that  i put it on a block and let it 'idle', but it was taking FOREVER.. it was barely through half a tank and THAT took like 45mins to an hour~ any suggestions??

also any suggestions about how to deal with the high reving? I tried playing with the idle screw, but if i set the idle any lower it would turn off.

i replaced the servo box and it is fixed now but it took alot of altering of the new arm it came with it didnt fit right but now it works good i replaced it with a metal gear

Check the needles. The LSN could be set too lean. When you break in the engine you want it on the rich side but obvisously you have to play with the idle a little to get it to stay running. I prefer the heat cycle method for break in over the idle on the box way.
Here is another break in method you might want to look at.
http://trackstarrc.com/trackstar/ind...&Itemid=89

If you have to keep the brakes on to keep it from reving you may have to take the throttle arm off and reposition it. It may have been set wrong from the factory. Just unscrew it, pop it off, center the servo and replace the arm.
Good luck. Let us know how it goes.