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defective, broke, or slipping?

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perhaps. You can check the clutch assembly but before does your engine clutch seem to slip? Like you accelerate and it just revs and then engages. Have you checked the slipper assembly? Is it on too loose?
 
I messed with that. I loosened it up first, made it worse. Then I tightened it up to a little tighter than factory. Improved a tiny, tiny bit. I'm gonna head to the LHS in a bit, see what they tell me. I'll keep you posted. Thanks for all the help.
 
no problem I definitely want to know what happens!!
 
red baron said:
The guy at the LHS gave it a tune up for our altitude, he said. He messed with the HSN, LSN, and the idle. Still running pretty rich. Here's a picture...is this normal?
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I try to make photo from same angle of my slipper clutch. The mine looks diferent.

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Red Baron, let me get this straight. On your first and only tank, the car will start, and when first trying to make it move it is a little hard to get moving as it takes quite a few revs, and then it engages and goes, and after the 2 second 1/4 throttle period, you back off, brake, stop and try to repeat, right? And then it either stalls or will not move again no matter how much throttle?

If that scenario is correct, I still would try to finish one more tank to see if it gets better, AFTER resetting the carb to the factory break-in settings. If it still does the exact same thing after the second tank, I then suspect the clutch is bad, but it could be as simple as a bad spring plate or no lube on the shaft allowing the clutch to slide back and forth smoothly like it should. Once the motor and shaft gets hot the shaft binds the clutch.

BTW, your photos look normal, but the gap is so small it may be hard to tell by just looking at photos.
 
Revo Rancher,

That is correct. But, the good news is that I did the second tank and the difference is remarkable. I had no problem whatsoever. When it first started up, the tires would turn if I didn't apply the brakes, but that only lasted about one minute. Right at the end of the second tank, it suddenly got a surge of power. Wow! This being my first Nitro R/C, I didn't know what to expect and whatnot. I'm going to wait until tomorrow to do tank 3 and see what happens after that. I will post after tank 3 so that I can update on the results.
 
A few years back, when I bought my first nitro truck, the LHS did the break in for me. He left the glow ignitor on for the first three tanks, since it was set too rich to idle without stalling. That's also the common break in practice for most airplane engines. Do it that way, and if it continues to stall, lean out both needles about 1/16th of a turn. Keep us posted. We'll get it up and running soon enough.
 
sounds like you should hange a glow plug. One of my Revo's didn't want to run after the first tank, we changed the glow plug and it ran flawless all the way to the 4th tank, I will run the 5th and final tank tomorrow.
BTW, One Revo started up a little reluctantly, but then ran fine. The other wouldn't fire for anything. Enter the heat gun! Started in about 10 seconds!

Uh, that's "Change", not Hange
 
Red Baron, I believe it is essential to the break-in process to do all 5 steps together. I do not think you have caused any irreparable harm, but please consider finishing the last 3 stages together.

I say this because if you read the break-in process carefully you will note a specific set of timed events, all linked. It appears it is necessary for all events to occur in succession in order to allow a certain heating/cooling experience to occur. I did mine all together and in order to check on your issue, I ran mine today through one tank, first fire up after break-in. NO PROBLEMS! Ran like it did on tank five. I think I need to lean it out for performance, but right now it is sooo strong, power is not an issue. :idea:
 
Revo Rancher said:
Red Baron, I believe it is essential to the break-in process to do all 5 steps together. I do not think you have caused any irreparable harm, but please consider finishing the last 3 stages together.

I say this because if you read the break-in process carefully you will note a specific set of timed events, all linked. It appears it is necessary for all events to occur in succession in order to allow a certain heating/cooling experience to occur. I did mine all together and in order to check on your issue, I ran mine today through one tank, first fire up after break-in. NO PROBLEMS! Ran like it did on tank five. I think I need to lean it out for performance, but right now it is sooo strong, power is not an issue. :idea:
Click to expand...

I will do the last three tanks in the morning. I'm going to put a small sock over the head to keep it in the proper temp. range because it's only going to get to 34 degrees for a high tomorrow. I will post afterwards and keep everyone posted.
 
Ok...I'm actually going to have to wait until Christmas Day to do the last three tanks of the break-in process because it's going to be about 22 degrees when I would be able to get to it...too cold for it I think. So, it will sit and wait :angry: until Christmas Day...
 
Good luck on your Revo and Merry Christmas!

I know you will love the performance once you get through all the break-in!
 
Revo Rancher said:
Good luck on your Revo and Merry Christmas!

I know you will love the performance once you get through all the break-in!
Click to expand...

Merry Christmas too you!!

I finished up the break in period this morning. During the third tank, it all of a sudden got faster. During the fifth tank, it would move fast, but would not shift into second gear. I turned the high speed needle 1/8 turn a few times, probably for a total of 3/4 turn...still would not shift. Still blue smoke coming from the exhaust. I even adjusted the transmission shift point... (3) 1/8 turns counter clockwise...still no shifting to second. I don't know how much I can lean the HSN before it's no longer safe as my temp. with the body on was hitting the 270 mark (measured with a on-board temp. gauge I put on) about 3/4 into the fifth tank.

I took the body off and the temp stayed at about the 230 range, but it would still not shift to second. :\ My idle also is very high...I tried to adjust it but really didn't see a difference. I read my manual and saw that I should have moved the throttle trim back and then adjusted it...I'll try that again. I'm going to cut some holes in the body to try and get some more air to the engine. Any advice on the shifting, anybody? Oh...I changed my glow plug after the fifth tank, so that's taken care of. Anybody want to give me their :2cents:?
 
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Neeeevermind....I took it out today and used Top Fuel and it shifted into second with no problem. I just need to fine-tune it and probably raise the idle a little bit as it is fluctuating like it wants to die. My temp reading is between 240 and 250. Runs like a beast! Thanks for all the advice. I will post pictures later on. :cheers:
 
To adjust your idle, turn your throttle trim all the way down. The ONLY time you up the trim is for starting it, or warming it up. With the throttle trim turned up, you also change your brake setting.
Since you lowered your idle screw without turning your trim down, it is probably too low now, so adjust it to about 1/16 opening, with no trim.
 
Rolex said:
To adjust your idle, turn your throttle trim all the way down. The ONLY time you up the trim is for starting it, or warming it up. With the throttle trim turned up, you also change your brake setting.
Since you lowered your idle screw without turning your trim down, it is probably too low now, so adjust it to about 1/16 opening, with no trim.
Click to expand...


Cool, thanks. I'll probably do that later on if not tomorrow. I want to take it to the track at the LHS and test out the jumps they have.

I cut the front part of the body that stuck out beyond the bumper, cut two holes behind the bumper and then cut-out the grill in order to improve airflow. Seems to have worked...saw lower temps. today. I just need to get that LSN set right. :smoke:
 
The LSN is very important for off the line punch, but also has a lot to do with engine temps. Be careful there. I once worked on a guy's MT that he had purchased from a pawn shop and knew nothing about. When I got it started, I just let it idle while I waited for the temp to stabilize. After barely 3 minutes of just idling on a table, it hit 310. When the LSN is too lean, NOTHING you do with the HSN will bring down the temp.
Hopefully you have a good temp gun to check it with.
 
I have the digital on-board temp. gauge by Traxxas on it. At one point during the driving, the temp hit about 280 but I did a low speed pass and the temp. went down to about 255. I'll get that LSN checked out upon starting it up next time.

Also, do you know a good place to get Top Fuel, 20%? My LHS only carries 33%. I bought Sidewinder 20%...seems like I had better results (temp. readings, was able to shift to second) with Top Fuel.
 
Tough call on shipping fuel. There's a $30 hazmat (hazardous material) fee with gallons. Quarts don't have it.
Normally I always ran Blue Thunder 20% in my 2.5, and since I'm the guy who tunes all the engines at the track, I started wondering why other 2.5 Tmaxxs were hitting higher RPMs than mine. A guy there gave me a couple of tanks of Traxxas Top Fuel, and after I re-tweeked mine, it was like a brand new engine. There's something to be said for running Traxxas fuel in a Traxxas engine.
By the way, next time you start it, if it's warm where you are, do the idle test on it. It's something most guys don't do. They just lean it till it wheelies off the line, then keep messing with the HSN to cool it down. Then the top end suffers.
 

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